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Unusual engine problem

Yesterday's Tractor Forums
S

Stephen Newell

Well-known Member
It's a 258 inline six engine in a 1975 Jeep. It has been used for 53000 miles in 23 years. The problem is recently it jumped time. OK so I tear into it and find the timing chain had a lot of slack but it didn't jump time there. The dots on the gears still lined up. I went ahead and replaced the chain and gears and manually set the time and put it all back together and then once I got it started finished setting the timing with a timing light. I then drove it a half mile and it jumped time again. I towed it back to the shop and managed to get it running again and put a timing light on it and the timing mark on the balancer was no where to be seen. I brought the engine back up to TDC again and pulled the distributor cap and the rotor was pointing to the #6 wire. I then move the #1 wire to the #6 spot on the distributor and rearrange the wires to the correct firing order and the motor runs great again. I then try to drive it again and it quits again. I then get it back to the shop and bring it to TDC again and the rotor is pointing back to the #1 spot on the distributor again. I then pulled the timing cover again and the chain is correctly installed. I then take the chain off and rotate the camshaft four revolutions while holding the rotor on the other hand putting a little pressure on it and it doesn't slip. Earlier I did have the distributor out and there isn't any excess wear on the gear and can't see any damage on the gear on the camshaft. Running out of ideas of what to try. I know the engine is a 4 stroke and know how to bring it to TDC so that isn't it.
 

What if the roll pin holding the dis.drive gear is broke or sheared???
There might be enough pieces of it to "act" normal when your wiggl ing things by hand.
But under load it slips and catches again.
 
A couple things come to mind.

When you first started diagnosing, where was the rotor pointing at TDC? When a chain jumps it will not go to 180* out, it will be only a few degrees out, usually retarded 15-30* not a full 180*.

If it really is getting 180* out, the only thing I can come up with is the roll pin in the distributor drive gear is sheared and turning 180 and temporarily catching the edge of the hole. If the same gear drives the oil pump, it is putting a considerable load on the pin, more than you can by hand.

You are bringing #1 up on compression each time you check the distributor position?

Is the timing mark on the balancer on a rubber mounted ring? They can slip, but again not exactly 180*. It would be random and once it is loose it would never return to the same place.
 
The end of the shaft which has the gear does turn the oil pump. The timing mark on the balancer is on a rubber mounted ring however it's still intact and hasn't moved. A couple days ago I thought it may be the balancer so I ordered a new one. The timing mark on the new balancer is the same as the old one so that wasn't it. Also I had painted the balancer and the paint was undisturbed while all this was going on.

I did bring the #1 piston up to it's compression stroke every time I checked the distributor.

The pin on the distributor I could see through it since it is hollow but I went ahead this evening and took a drift punch and removed it and it was not sheared.
 
Back when that happened to him I pull the rotor off not knowing it had spun out of place and put it back on and it ran till it slipped again then I took a better look at things and sure enough you could see what was going on. I've probably still have parts and pieces of that type engine laying around
 
The rotor on mine has a big notch in it that you can't put on without fitting it into that notch. It's firmly mounted in the distributor.
 
It's not loose, I've been using it to put resistance on the distributor gear trying to check if the gear is loose. I've been rotating the camshaft while holding the rotor.
 
The one on this Toyota I could not make spin out of time but it would do is some how. Not sure if it was the cap or rotor or a combo of both the the rotor maybe working it way up to the point it could spin
 
(quoted from post at 21:11:13 05/21/21) It's not loose, I've been using it to put resistance on the distributor gear trying to check if the gear is loose. I've been rotating the camshaft while holding the rotor.
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sheared woodruff key on the crank gear or cam gear. Got me once long ago. Have you checked either of those? It sounds like you have checked all the other possibilities. Paul
 

"it jumped time"

HOW did you arrive at that diagnosis????

Seems like a lot of work to tear it down to the timing chain and sprockets only to find out it didn't???
 
Reread and see that new gears and chain went on so keys should be good. If the cam and crank timing is not changing when the distributor is changing it's timing, and the roll pin is not sheared,is there a mechanical advance in the works, ??
 
Two ideas. Look down the distributor drive hole and see if there are missing or partial teeth on the cam. Is the centrfugal advance getting stuck or broken? Since getting the ignition to fire correctly for a short time makes it run, it is not the cam drive. Jim
 
A long shot but is the distributor gear engaging the cam gear enough? Not machined right at the factory?
 
I don't know how else to describe what is happening. The #1 cylinder at TDC switches from #1 to #6 position on the on the distributor cap and back.

On this Jeep it's less than an hours work to get the timing cover off so it's not that much work. There is something very wrong somewhere and if I don't tear into it I will never find the problem.
 
The only thing I haven't fully checked is the cam gear. I would have to pull the head and lifters and the grille of the jeep to get the cam shaft out to inspect it better. So far I can only look at it through the hole where the distributor was. There is no teeth
broken and I tried to rotate the gear with a wooden dowel rod and couln't.
 
I believe it is but not sure. When I bought the Jeep in 1997 the 232 engine in it was worn out so I bought a 258 factory remanufactured engine and put in it.
 
I've been wondering the same but I've used the engine for 53000 miles without a problem. Looking at the cam gear through the hole it appears the teeth on the gear seem more shallow than the one on the distributor. I still have to thread the gears together when installing or removing the distributor.
 
If the gear on the cam was broken or worn or mismatched with the distributor, the distributor gear would show signs of being damaged or covered in metal flakes.

The gear is machined into the cam casting, so it can't be turning on the cam.

Next time it quits, before moving the distributor, take the valve cover off, watch the rockers on #1 and #6. Turn the engine through, the rotor should point to #1 when #6 rockers are in overlap, then one rotation of the crank, just the opposite, point to #6 when #1 is in overlap. That is the no guess method to be sure it is in time.
 
The gears on the camshaft don't seem as pronounced as what is on the distributor but there is no broken or damaged teeth. I looked at the centrifugal advance this morning and everything seems in order. It's freely moving and no broken or missing springs.
 
I bring the #1 piston to it's compression stroke with the indicator mark on the harmonic balancer were it's suppose to be. That much is staying constant. It's only the distributor which is moving back and forth. As unlikely as it sounds I think the gear on the camshaft is slipping. Not certain at this point but I think I will have to pull the engine to get it out.
 
I thought as much that the gear on the camshaft wasn't held with a pin, especially since the gear is in the center of the camshaft.

It wouldn't surprise me that motor company put a badly worn used camshaft or a really cheap one in that engine. I couldn't believe the condition of the gears with the old timing chain that was on it. I've replaced timing chains on a engine that had 180,000 miles on it that wasn't worn as much.

I do plan on putting the engine back together today. I believe on this engine the camshaft is held in from the back of the engine so if I'm going to take it out I will have to pull the engine to do it. I will need the get the jeep into another building to do this so I will need it running.
 

I was gonna ask if this 258 has had a GM HEI installed, but your other posts indicates no.

I seem to remember you can get a pretty good look at cam and dis. gear together if you drop oil pan out of the way.
 

You are either confused/inconsistent at finding #1 TDC at the end of the compression stroke or something in the distributor, possibly the advance mechanism is slipping out of place.

NO WAY either the timing chain and gears or the distributor drive gears are going to "jump time" EXACTLY 1/2 turn REPEATEDLY.

Note that if you "think" you have the crankshaft @ #1 TDC at the end of the compression stroke and are in error by one turn, the rotor it will be pointing to #6, just as you are seeing.
 
If it was at the exhaust stroke the exhaust valve would be open but it's not when I bring the #1 cylinder to TDC. Both valves are closed.
 
You are mistaken. Both valves are closed at TDC ALWAYS. Pull the spark plug and feel the air pushing out to find the compression stroke.
 
If you mean the pin on the end of the camshaft where you put the gear for the timing chain on then no it's not that. It's in good condition. The gear which turns the distributor I understand it actually one piece of metal with the camshaft since it is located in the center of the camshaft.
 
Stephen Newell,

You may not be @ TDC. Just seeing the valves closing doen not put you @ TDC. You NEED to take the pug out AND verify that the piston is @ TDC AFTER the valves are closed. You can also check to see if the timing mark indicator is at zero on the crank TDC mark.

If you want to find true TDC, there is a procedure to find that, but I think you need to be certain that you are @ TDC.

You should pull the distributor out and check the driven gear. It usually is softer then the cam, and does wear out,

Guido.
 
Could the rubber in the damper be letting loose, allowing the timing marks to shift?

Have you found a jeep owner's website that discussed common problems with that engine?
 
People have been implying that I've been on the exhaust stroke when I say I was at TDC. I was trying to say that when I was at TDC both valves were closed. With the engine fully assembled I was unable to turn the crank and reach the #1 cylinder to feel air coming out so I removed the valve cover to visually make sure I was at TDC. Anyway the crank and the camshaft are in unison. It's jumping time at the distributor somehow. At this point the only thing I can guess is the camshaft is bad.
 
No, the harmonic balancer while it had some minor cracks in the rubber it was alright. Since this had been going on I went ahead and purchased a new one and the timing mark on the new one is exactly the same.

Yes, I did post this problem on a jeep site but the thread is about run it's course with no answer. Someone there even pointed out the fact that if the harmonic balancer was bad it would't be causing it to jump time, just the indicator mark would move. By then I had already bought the blancer. I don't regret it though. When I get past this problem I don't want to see that balancer again.
 
It's what I meant, the piston was all the way up with the valves closed. Then at least at the beginning the timing mark was lined up at the harmonic balancer too.

Through that 1 1/4 diameter hole I looked at the drive gear as best as I can. From what I understand the gear and the camshaft on this one is all one piece of metal. The gear is located in the center of the camshaft so there really isn't a way to install just the gear. Having said that though I think it likely when they built this motor they used a used camshaft or some cheap brand x camshaft. I know the timing chain set was junk for it to wear out at 53000 miles. There was probably an inch of slack on the chain before I replaced it.
 
I haven't pulled the shaft out of the distributor but yesterday I rotated the camshaft 4 revolutions while holding the rotor and couldn't make it slip. I have had the distributor out and removed the pin that turns the drive gear and it is intact. The shaft itself is
about 1/2 in diameter. I can't imagine it would break without some event like a stuck valve or froze up oil pump. Then the end that goes into the oil pump is ground to a point like a blade screwdriver. It would break off the point before it would break the shaft.
 
Mark a tooth on the distributor drive with metal marking paint, and the same for a tooth on the cam (do it with the timing gears aligned to TDC so the tooth can be found. Put the distributor back in so the teeth match and it is in time. When it quits, observe the marks for consistency with the way it was assembled. If the gear is slipping, it will be obvious. Make sure the distributor lower bushing is not egg shaped. Also look at the wear pattern on the driven gear for partial engagement. Jim
 
There just isn't space to be able to do that. It's difficult enough just to get the gears together and line up with the oil pump under it. Sometimes I have to insert the distributor several times just to get the rotor pointed the direction it should.
 
(quoted from post at 10:12:33 05/22/21) There just isn't space to be able to do that. It's difficult enough just to get the gears together and line up with the oil pump under it. Sometimes I have to insert the distributor several times just to get the rotor pointed the direction it should.
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At this point I suspect there's a poor connection or short that causes it to lose spark and stop, then when it cools and/or you muck with the distributor and wiggle things around it works for a little while and the cycle repeats.

I think you've just got yourself convinced it's "jumping time".

If it actually is REPEATEDLY "jumping time" exactly a half turn it's gotta be the most bizarre mechanical problem ever!

On the other hand, has camshaft endplay been checked, NOT sure, offhand, exactly what limits that in your specific engine.
 
Here is where I'm dealing with. I replace the timing chain and finish adjusting the timing with a timing light. Then I drive it a short distance and it quits. I get it running again with the timing light attached to it and the timing mark on the harmonic balancer is
gone. It's no where near close to what it was just before. Then I discover the rotor is pointing in the opposite direction so I rewire the distributor to match where the rotor is pointing and it runs great again for a short distance and reverses itself again and
quits. I don't think it is an electrical problem. Without making any adjustments on the timing I've driven the jeep with the plug wires switched 180 degrees both ways. How is that for weird?
 
Everyone is making comments that would normally cover the problem. Bad timing Chain, gear issues and sheared pins or keys.

I once had a distributor that had worn bushings in the distributor shaft that allowed the engine to slip time. Seems there was one spot in the Bushings that allowed the distributor gear to jump time. But it should be really noticeable.

You wouldn't happen to have a bent or twisted camshaft ?
 
The shaft would lift up and down maybe 1/16 but there was no side movement. I have just installed the distributor and manually set the timing again do I can't check for a bent shaft right now. I've been thinking maybe I should take the distributor to the machine shop I use and have them check it out. I thought about it today but they are closed on Saturday. I expect to continue to have problems with it and before I pull the motor I'm going to get them to check it out first.
 
The spots are small and in the middle of the teeth. It looks more polished than anything. It's certainly not on the corners of the teeth which would suggest slipping. It could be since it just started this it hasn't had time to do much wear. Someone also suggested that maybe the distributor shaft may have bent. I had it installed back on the jeep before I could check that out so that didn't get done. Tomorrow I will try starting it again and see what happens.
 
(quoted from post at 16:49:19 05/22/21) The spots are small and in the middle of the teeth. It looks more polished than anything. It's certainly not on the corners of the teeth which would suggest slipping. It could be since it just started this it hasn't had time to do much wear. Someone also suggested that maybe the distributor shaft may have bent. I had it installed back on the jeep before I could check that out so that didn't get done. Tomorrow I will try starting it again and see what happens.
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Replace the distributor,done. Who's with me? The process of elimination is pointing that way,unless valve overlap is not understood, even then, swapping the wires and then swapping them back is the flag. The crank and cam timing has not changed,the gear mesh between cam and dizzy is not at fault.
 
nothing makes sense , so pull the distributor and take it apart ,... long shot but the mech. advance may be slipping on the main shaft. just thinking this cause if it would slip it would have to slip 1/2 a turn. unless i am dreaming. like to see a pic of that dist taken apart to know for sure.
 
My camera is in worse shape than the jeep so unable to take any pictures. I looked at the mechanical advance and didn't see anything obvious wrong with it. Never saw it before yesterday so don't know how to make sure it isn't slipping.
 
So you don't think there is slippage between the cam gear and the distributor gear? I've been currently trying to get the jeep in a place where I could pull the crankshaft and replace it. I would certainly would rather not do that.
 
(quoted from post at 06:40:30 05/23/21) So you don't think there is slippage between the cam gear and the distributor gear? I've been currently trying to get the jeep in a place where I could pull the crankshaft and replace it. I would certainly would rather not do that.
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I would definitely disassemble the distributor and look for trouble there before pulling the engine/cam etc.
Your description of what you have done so far is as good as a pic or two,but a cheap phone to take some pics costs less than say a new balancer.
There are folks on this forum who are very good at diagnosing from thought and experience, and love when these kind of situations are resolved.
 

I will have to look a little deeper and pull up a few pix... Is it possible this is one of those engines set up like some Fords the timing marks on the crank/cam aling with the timing 90deg out...

I am at the point the valve cover would have to come off and verify "on the rock: to eliminate a mechanical issue.

Note, YES it possible for the chain and gears to show considerable ware at 50K. I would not base my strategy its cheap parts...
 
Did you turn the crank and watch the valves to achieve tdc? I always roll it until i see the intake open and watch it close as i continue around to comp stroke. Then there's no ? as to where i am in the cycle. fred
 
(quoted from post at 19:27:47 05/21/21) It's a 258 inline six engine in a 1975 Jeep. It has been used for 53000 miles in 23 years. The problem is recently it jumped time. OK so I tear into it and find the timing chain had a lot of slack but it didn't jump time there. The dots on the gears still lined up. I went ahead and replaced the chain and gears and manually set the time and put it all back together and then once I got it started finished setting the timing with a timing light. I then drove it a half mile and it jumped time again. I towed it back to the shop and managed to get it running again and put a timing light on it and the timing mark on the balancer was no where to be seen. I brought the engine back up to TDC again and pulled the distributor cap and the rotor was pointing to the #6 wire. I then move the #1 wire to the #6 spot on the distributor and rearrange the wires to the correct firing order and the motor runs great again. I then try to drive it again and it quits again. I then get it back to the shop and bring it to TDC again and the rotor is pointing back to the #1 spot on the distributor again. I then pulled the timing cover again and the chain is correctly installed. I then take the chain off and rotate the camshaft four revolutions while holding the rotor on the other hand putting a little pressure on it and it doesn't slip. Earlier I did have the distributor out and there isn't any excess wear on the gear and can't see any damage on the gear on the camshaft. Running out of ideas of what to try. I know the engine is a 4 stroke and know how to bring it to TDC so that isn't it.
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tephen, do not believe everything that is posted in the 5 pages of this thread.
 
Just thinking out loud now. When you got the jeep it had a different engine in it, correct? You then purchased a different engine to put in it. Did you purchase a complete engine including the distributor? You said that the end of the distributor shaft is like a flat blade screwdriver? Is the end of the shaft worn, as that could explain it going 180 degrees at a time? Is it the correct distributor for the engine or have you just been lucky for 53000 miles?

Steven
 
One more thing. Can you get a measurement from the base of the distributor to the drive down by the cam to see if you are getting proper engagement?

Steven
 
I've never done that however it's a spiral gear and you have to thread the gears though each other to get the distributor all the way in.
 
The distributor came off the original engine. The end of the distributor wasn't worn. It just turns the oil pump anyway. I believe it's the correct distributor for that engine but I really can't say for certain. It fit in just the same as the old engine. The only difference between the 232 engine and the 258 is the displacement. Everything else is the same.
 

Its one of those crazy ones : ( its not at TDC with the cam/crank gear marks aligned... I have a PFD dunno how to post it.

I can copy and paste one I don't like it...

Remove the drive belts, engine fan and hub assembly, accessory pulley, vibration damper and timing chain cover.

Remove the oil seal from the timing chain cover.

Remove the camshaft sprocket retaining bolt and washer.

Rotate the crankshaft until the timing mark on the crankshaft sprocket is closest to and in a center line with the timing pointer of the camshaft sprocket.

Remove the crankshaft sprocket, camshaft sprocket, and timing chain as an assembly. Disassemble the chain and sprockets.

Assemble the timing chain, crankshaft sprocket and camshaft sprocket with the timing marks aligned.

Install the assembly to the crankshaft and the camshaft. Double check the alignment by counting the number of links or pins with the sprockets positioned as illustrated.

Install the camshaft sprocket retaining bolt and washer and tighten to 45-55 ft. lb.

Install the timing chain cover and a new oil seal.

Install the vibration damper, accessory pulley, engine fan and hub assembly and drive belts. Tighten the belts to the proper tension.


mvphoto75825.gif


AT TDC #1

mvphoto75826.gif
 
I didn't count the links on the chain but I did have the dots on the gears lined up like what is illustrated when I installed the new chain. I know it wasn't quite at TDC but I set that later after the chain was installed. The gear on the camshaft had a pin on it
where you pretty much had to have it lined up to get the chain on. I thought I still had the old chain and sprocket around but it got tossed. It happened to be the same timing set that was on there before. It is a Enginetech TS494B.
 
Stephen,After reading your post I can only think that the distributor may not be 100 right.I would check into that before pulling your hair out second guessing what you have already done.Good luck and post back with the out come
 
I don't but I appreciate all the ideas. I just need to check every one of those to eliminate the possibility of being the problem.
 
From the AMC shop manual.... to check valve timing, remove valve cover and spark plugs, rotate crankshaft until number 6 piston is at TDC on compression stroke.....set the valves on number one to .003 inches clearance, and rock crankshaft back and forth.The exhaust valve should open before the TDC mark on the pulley lines up with the pointer....measure the actual distance. The intake valve should open the same distance past the pointer....if it varies more than half inch, remove the valve cover and inspect timing chain.
This may help...a long shot but if the distributor is from a 232 and being installed in a 258....an engine with a longer stroke and maybe a deeper block...maybe the distributor shaft is not long enough to fully engage it's drive.

Just a thought...hope it helps.

Ben
 
One question, when you install a timing chain if you line up the dots on the gears like the illustration Hobo posted can it be wrong? I have the engine back together now and drove it several times but it runs a bit rough and there is a knocking noise which sounds like it's coming from around the #1 cylinder. I went all over it with a mechanic's stethoscope and couldn't hear the noise anywhere. The only accessory on the motor is the alternator and the noise doesn't seem to be coming from there.

I can't seem to recreate the original problem which started this thread.

I printed your info and will check it out tomorrow.
 

Not to say this is your issue they are know to crack/break piston shirts off. It sounds like a valve rocker that's worn out.

All that I have worked on that ran extremely hot I put pistons and rings in it to be on the safe side. The last one I worked on for a noise as I described the piston came apart on a test drive it knocked a hole in the water jacket : ( A broke piston was the issue...

$7400 later the knock/tap was gone : )
 
The manual I have shows the same illustration as hobos. The note below says....on 6 cylinder engines, locate the marked cam tooth at the 1 o'clock position, Mark on crankshaft gear should be approximately at point of mesh. Count the number of links between the marks, 15 pins or 7 1/2 links.

Hope you find the problem...who would think that a simple old school 6 banger could be so hard to time. Good luck!

Ben
 
When I put the sprocket on the camshaft the pin was in the one o'clock position. I just got to wondering if you could rotate the camshaft another revolution and have it out of sinc with the crank.
 
It's a lower tone than the knock from valve rockers. I will take the valve cover back off tomorrow and see If that sheds some light. I may also drop the oil pan and see what the connecting rods look like.
 

If you had the dots aligned I doubt its out of time. Now if you reset the distributor to # 1 TDC with the dots aligned that may be an issue. If that's the case I doubt it would have fired up without resetting the distributor....

If its getting 180 out why is 180 a pattern even if there was an issue with the cam are dist why does it seam its out 180. Gear/dist issues would not have a pattern..
 
What I did was rotate the crank and the camshaft to where the dots lined up to put the chain on. Once installed I then rotated everything to TDC. That chain went on very tight with zero slack. On counting the links, the chain went on so tight there isn't a way I
could have put more or less pins between those points on the gears. I could have maybe done that with the old chain but not the new one. I can't see pulling the timing cover again to check it. That harmonic balancer was the hardest part of the whole project. Not so
much getting it off but putting it back on.
 
That's what I've been doing is beating it on until it's far enough to put the bolt on' I thought about purchasing a longer bolt but the installer looks much better. I'm wondering now if beating the balancer on has caused the knocking noise I'm looking for.
 
Another question I'm confused about. The firing order on this engine is 1-5-3-6-2-4. AT TDC setting the distributor at 0 degrees the rotor is pointing just after the #1 spot on the cap. At 8 degrees it's not as far past #1 but still it. Is this correct? I thought the plug was suppose to fire just before TDC.
 
(quoted from post at 09:55:41 05/24/21) Another question I'm confused about. The firing order on this engine is 1-5-3-6-2-4. AT TDC setting the distributor at 0 degrees the rotor is pointing just after the #1 spot on the cap. At 8 degrees it's not as far past #1 but still it. Is this correct? I thought the plug was suppose to fire just before TDC.
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otor is only /needs to only be "close"....you should pay attention to points opening as to when spark occurs. You probably have EI & no points,so can only go by when coil current is shut off, i.e., timing light.
 
(quoted from post at 13:31:35 05/24/21) It does have points. I did double check the gap and was alright.
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y point was not the specific gap, but rather the point in rotation that points start to open is the time of the spark, & that may not be exactly where the rotor is pointing. The width of the rotor metal tab combined with the with of cap tower contact allows for some variation in exactly where rotor is pointing at time point contacts begin to open & spark occurs.
 
Caveat: Have read none of the previous posts.

Are you sure that the outer part of the balancer is not moving on the hub rendering the timing mark inaccurate?

Dean
 

You should have looked for 4.0Jeep engine..
Never have I seen an engine use as much gas as my old 258..!
The 4.0 L Fuel Injected and runs like or as good as a Small block Chevy..!
 
The distributor drive gear may have a sheared retaining pin . Broken distributor shaft? Sheared key on camshaft gear maybe? from your description Im thinking distributor is probably the culprit.
 
The pin isn't sheared and the camshaft is one piece and neither appear to be severely worn. The shaft on the distributor isn't broken either. Right now I'm trying to drop the oil pan and remove the oil pump and see if I can inspect the gears from the underside. It does seem to be distributor related.
 
The balancer was alright and matched the new balancer I bought and replaced it. I can't seem to re-create what it was doing. Somehow it was jumping time 180 degrees at the distributor.
 
Don't believe I will every find out what the cause of the timing jumping. I pulled the oil pan today to get under it and inspect where the distributor gear fits into the cam gear and it's tight. There can't be any slippage there.
cvphoto89673.jpg
 

Too bad you didn't have a borescope inspection camera. Could have run it up through the drain hole without removing the pan. Also run it down from the top to look at the gear.
 
I used to have a cheap one which didn't last very long. Very often the resolution was so bad you couldn't make out details like that. In any case the pan had a bunch of sludge in it which needed to be cleaned out and the exterior painted so it wasn't a wasted effort.
 
In your pic it looks looks like metal shavings where the gears meet also it looks like just the end of the dist gear is making contact
 
(quoted from post at 10:45:35 05/26/21) In your pic it looks looks like metal shavings where the gears meet also it looks like just the end of the dist gear is making contact
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also see the photo as looking like the gears are not making full face contact, but sure fail to see that as a cause for a 180 degree jump & then correcting itself with another 180 jump. Just call me a skeptic, but I just don't see the possibility. I will be far more than really surprised if it is ever shown that such is the case and a reason for it.
 
(quoted from post at 11:45:35 05/26/21) In your pic it looks looks like metal shavings where the gears meet also it looks like just the end of the dist gear is making contact
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Wear pattern on the cam gear starts at the end of cam gear and increases aas it gets to center of cam gear face.
It is a good pattern. The outer ends of the two gears are not going to wear as much as the center face of teeth.
 
From the wear on the distributor gear I believe you are right about it not making full contact. The picture didn't come out as well as I hoped, I believe the gear picked up some sludge installing it which filled the gear. I tried to clean it out with a paint brush
but without pulling the distributor I can't get it any cleaner. With the end of the distributor inserted into the oil pump I don't see any possibility of the gears slipping either.
 

If there was an issue with the gear it would have worn out are tore up the dist gear you can bank on that... It would not be a guess it would have jumped out at ya...
 
I had intended to pull a trailer with the jeep and thought since I was replacing motors the larger engine would be better. Ended up being a waste, the jeep was really too light to pull a trailer that didn't have brakes of it's own.
 
Whats your rotor look like? Is it seated like it should be and fairly snug? An old man neighbor told me a story once about a car he had where the rotor would jump up off the shaft. I cant remember the details, I would think it would have destroyed the cap though. But If this was possible and even more unlikely that the rotor reseated itself , then that could explain why the ignition timing was always 180 degrees off. Just spitballing here. J
 
(quoted from post at 20:48:54 05/26/21) Whats your rotor look like? Is it seated like it should be and fairly snug? An old man neighbor told me a story once about a car he had where the rotor would jump up off the shaft. I cant remember the details, I would think it would have destroyed the cap though. But If this was possible and even more unlikely that the rotor reseated itself , then that could explain why the ignition timing was always 180 degrees off. Just spitballing here. J
Click to expand...
don't think so.
 
Yes, that was investigated. I turned the camshaft four revolutions while holding the rotor and couldn't make anything slip. Looking at it on the inside there is no evidence of it slipping and the way it's made I don't think it could be lifted enough to slip with the cap on.
 
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