1948 Model C Engine knock

[vzuden]

I have had my C for over twenty years and after replacing the clutch, radiator, and valve guides/seats when I first got it have had absolutely no trouble...until today.
I use this tractor for mowing (Woods belly deck) about an hour per week from April to October. Today it started right up after sitting all winter. I let it warm up and then drained the oil. I found two pieces of shiny metal in the oil drain pan. They are 1/2 inch long and appear to be gear teeth.
Since the tractor had been running fine and sounding ok I continued with my oil change, lube and fluids top off. Started it up and everything seemed fine. I made three rounds around my 5 acres and the engine started knocking.
I rechecked the oil and it was full. There is an oil pressure gauge mounted in the oil filter housing and at idle it was showing zero PSI. I increased throttle a little and the need moved ever so slightly. But the gauge is hard to see and I am not confident it works properly.
I parked it in the barn and drove home (property is 1 1/2 hours away) and got home and realized I didn't bring my service manual with me.
So I am looking for some input to think over before I go back over there and start taking things apart. I am guessing I need bearings.
1. Can the bearings be replaced by just dropping the oil pan?
2. What kind of gear is there that has 1/2 inch long teeth that would break off and land in the bottom of the crankcase?

 

[Jim Becker]

The oil pump is driven by the camshaft. You could have lost that gear (a lot of spiral to those teeth, you didn't mention any curve to the pieces.). The oil pump is reached through the pan, held in place by two bolts, through the lower part of the block.

One of the timing gears: crankshaft, camshaft, governor. You may end up needing all of them, but probably not. I'd probably start by pulling the governor and inspecting that gear and what can be seen through the governor mounting point.

You will probably lose timing when you pull the governor.

 

[fastfarmall]

If it says no oil pressure, that what you got, those old gauges were right on the money, from my experience!

 

[gene bender]

from prior experiences i would say those are the teeth from the gov gear.
Remove the gov housing turn the engine over till you see the two dots on gov
gear and on the cam are matched then look careful at the gov gear if it needs
replaced you will have the dots lined up so the engine is still in time

 

[560Dennis]

I have a knock on the Farmall c ,it would appear to be cam related .
Was told on the Fordson my crankshaft gear,camshaft gear were worn out ,if it didnt replace them it would sound like and engine knocking
sound was the results. I replaced them per recommendation, cant say what the results would be if I didnt got to much in vested in engine
to ignore recommendations.
I cant seem to find a new cam shaft gears for C,s ,maybe someone has a scource for them to share.
Also the block bore for camshaft is over sized results in low oil pressure. I have about two thousands oversized camshaft block bore
according to IT Manual s . Note there are no camshaft bearing inserts on the c113 or c123 engine ,bearing are the bores in cast iron block .
My tractor I use a heavy duty straight Sae 30 weight
Interesting post

 

[Fritz Maurer]

Pieces in the pan and no oil pressure... remove the
pan first.

 

[RedRamGT]

If you remove the oil pan, it's easy to drop the oil pump and check it out. There are two 3/8 bolts on the right side of the lower engine block, if you remove those two bolts the oil pump will pull out. Then, you can check the gear on the oil pump and see what condition it is in. If the engine is running and there is no oil pressure, the camshaft is (likely) okay - and something may have happened to the gear driving the oil pump or the oil pump itself may be damaged.

 

[gene bender]

why remove the oil pump no way any gears from the pump could get into the pan pump is totaly enclosed where the gears are.

 

[Fritz Maurer]

Gear drive at top of pump put pieces in the pan real easy.

 

[kshansen]

I would say dropping the pan and having a look at everything down there would be the first thing I would do. Even if it turns out to be something higher up at least you can be sure there are not any bigger pieces that just did not come out with the oil.

I'm kind of thinking that if it ran with the "tooth" missing but with no oil pressure that the first thing I would want to confirm is the condition of the pump drive gear and gear on camshaft that drives the oil pump.

Just had the pan off my BN and it is a simple job, just need to take off cover at the back that covers the flywheel. As you just put fresh oil in I would drain into a clean container and keep it covered so you can reuse it.

 

[vzuden]

(quoted from post at 18:46:35 04/30/22) The oil pump is driven by the camshaft. You could have lost that gear (a lot of spiral to those teeth, you didn't mention any curve to the pieces.). The oil pump is reached through the pan, held in place by two bolts, through the lower part of the block.

One of the timing gears: crankshaft, camshaft, governor. You may end up needing all of them, but probably not. I'd probably start by pulling the governor and inspecting that gear and what can be seen through the governor mounting point.

You will probably lose timing when you pull the governor.

The broken "teeth" are straight pieces. 1/2 long and about 1/8 inch tall and wide

 

[560Dennis]

I would go over the oil pump the aluminum covers warp and blow the gasket out or the shaft wears. There are no cam bearings in it.
Also
Replace camshaft worn soft plug , I T manual section 60 , loss of pressure

 

[kshansen]

the more I read and think about this problem come up with two thoughts.

First would be to replace the oil pressure gauge at least temporarily with a known good gauge to be 100% sure if you have oil pressure or not. I'd run only long enough to determine that a few seconds should give you an answer!

Second would be that if this "tooth" did come from somewhere inside the engine you need to get serious about finding where it came from before there is a major failure.

Pulling the pan should let you see at the least the crank gear. Next removing the governor should let you see some more gears

 

[gene bender]

Why are you waiting to pull the gov housing off so you can see where the teeth are missing. No teethe on oil pump are that size
and crank gear teeth are longer. So quit messing around and pull the gov housing

 

[Fritz Maurer]

He probably will if you just keep your shirt on... all we know so far is what came out the drain hole... might be more evidence...gonna have to come off sooner or later...unless you think he should just leave broken parts sloshing around in the pan...

 

[vzuden]

(quoted from post at 05:36:36 05/03/22) He probably will if you just keep your shirt on... all we know so far is what came out the drain hole... might be more evidence...gonna have to come off sooner or later...unless you think he should just leave broken parts sloshing around in the pan...

I plan to pull the pan tonight. I will need to check the rod bearings since it was knocking and since there are only two bolts (as described earlier) holding the oil pump I will drop it down.
I have a parts manual and a service manual but the line drawings make it difficult to tell which gear teeth I found in the oil.
Assuming I need bearings, any advice on which to try to locate? The old parts manual lists three (or so) different sizes that were available back then.

 

[Fritz Maurer]

You wont know what bearings to order until you
have and old one in your hand. The crank may
have been turned at some point before you owned
it.

 

[vzuden]

Thanks for the tips gentlemen. I decided to pull the pan first since I needed to know how much shrapnel could still be in there but...
I needed to move the tractor from my barn to the shop. I started it, and it ran fine, but the engine was knocking and I only had to move it 75 feet. I kept the RPM low and drove it the door of the shop and turned it off. Opened the door, restarted it, it ran fine and no knocking AND the oil pressure was now up - probably midpoint on the gauge. Still, I carefully pulled it into shop.
Drained the oil and went through it by touch and with a magnet. I found another gear tooth same size as the two found originally.
I pulled the oil pump and took the cover off. Gene, you were correct, the gear pieces are definitely not from the oil pump. Those gear teeth are much bigger than what I was finding in the oil.
Next, I grabbed onto each connecting rod cap and the front one had some play. My guess is it should be tight - do you agree?

I was looking up from below at near where the front of the cam is and I can see a gear with damage. I'm not sure what it is - maybe cam? The gear teeth on the front of the crankshaft looked good.
As suggested by a couple of you my next step will be to pull the governor cover. I was running out of time tonight and I looked at it briefly - It appears to come off towards the front of the tractor - is there room without removing the radiator?
Any tips or advice on pulling this cover?[/b]

 

[gene bender]

the teeth will stay on the bottom of the pan just what will pic them up no way to get into the oil pump

 

[gene bender]

loose up the fan belt and let the fan drop to the bottom of the slot it will
help removing the gov housing and removing it from the tractor.After removing
the housing turn the engine over till you see the two dots on the cam gear and
not the single dot as it lines up on the crank gear when you see the two dots
the gov gear will also have the two dots but they are hard to see but they will
be there matching the two on the cam gear. Also remove the dist cap to check
where the rotor is pointed so when replacing the gov gear you will still be in
time. If you want a replacement gov gear i do have some or STEINERS AND OTHERS

 

[Fritz Maurer]

May as well pull off the radiator, the whole front
bolster has to come off. Unless youre going to
chance it with broken timing gears.

 

[vzuden]

(quoted from post at 05:33:07 05/04/22) the teeth will stay on the bottom of the pan just what will pic them up no way to get into the oil pump

I described the bigger pieces but there were tiny little slivers of metal also. When I pulled the oil pump off I saw where the paper thin gasket for the plate covering the two pump gears at the bottom was crumbling. I am more comfortable with getting all of the pieces out and eventually replacing that gasket.

 

[gene bender]

No need to pull the radiator the gov housing will come out without removing the radiator . The three bad gov gears i have found but never teeth gone on the cam

 

[vzuden]

I attempted to pull the governor housing off tonight or at least what I am reasonably certain you guys are referring to. I removed both the linkage to the throttle control and to the carb.
I removed four bolts (maybe 5) but this cover does not want to come off.
I pried on it, tried to get a screwdriver under it - no go. I couldn't get a gap to get under it. I tapped on it with a hammer and it will pivot about 1/4 inch both directions so I am sure there is not a gasket adhering it. What am I missing? Do I need to pull the distributor side off?

This post was edited by vzuden on 05/05/2022 at 07:36 pm.

 

[gene bender]

LOOK again there is still one bolt holding as the housing will fall off when
all the bolts are removed

 

[vzuden]

You were correct. I had missed a bolt as it was caked with grime. As you may recall I had found three gear teeth in the oil pan. I see now that two came from the governor and one came from the drive gear (camshaft?) In the pictures below the first two show the drive gear with missing and ragged other teeth and the third picture is the governor.
Questions
What do you recommend for the next step?
What would cause this? 75 year old metal?
Would this have caused no or low oil pressure?

This post was edited by vzuden on 05/09/2022 at 06:48 pm.

 

[gene bender]

i would replace the gov gear and go enough of the cam gear is still there

 

[kshansen]

(quoted from post at 01:23:52 05/11/22) i would replace the gov gear and go enough of the cam gear is still there

I would tend to disagree. If that upper picture is of the cam gear there are a few teeth missing the majority of the teeth!

I would be getting busy removing the front cover of that engine so I could see all the gear teeth.

And maybe start looking around for a replacement set of gears, maybe some one has an engine that has a cracked block or head who would be looking to sell parts.

Someone here must know what other engines use the same gear train! Would gears from a A, or B be the same? Or even a U-2 power unit work?

OK I'll answer my own question:

I see this on the parts page for this forum in reference to the cam gear:

For tractor models (100, 130, 140, 200, 230, 240, Super C all with 123 CID engine), (330, 340, 404 all with 135 CID engine), (424 with 146 CID engine), (444, 504 with 153 CID), (A, AV, B, BN, C, Super A, Super A1, Super AV, Super AV1 with 113 CID engine). Replaces 375712R1, 6779DB.

And this is what is listed for the governor:

For A, Super A, B, C, Super C, 100, 130, 140, 200, 240, 330, 340, 404. OEM number 375778R11, 374710R1, 356746R91, 356745R91. Does NOT include housing. Reference ID: R0612


This post was edited by kshansen on 05/11/2022 at 04:59 pm.

 

[vzuden]

I have rotated the cam gear to check all of the teeth and the pictures show the damage. There are a few teeth beyond these that are maybe a little rough is all

 

[vzuden]

Gene, you have a governor?

 

[gene bender]

YES I HAVE GOV GEARS 75.00 PLUSS POSTAGE [email protected]

 

[vzuden]

(quoted from post at 04:04:26 05/21/22) YES I HAVE GOV GEARS 75.00 PLUSS POSTAGE [email protected]

Thanks, but I didnt hear from you and I found one elsewhere. I hope to get it installed and everything back together next week.

 

[vzuden]

(quoted from post at 04:44:26 05/21/22)

(quoted from post at 04:04:26 05/21/22) YES I HAVE GOV GEARS 75.00 PLUSS POSTAGE [email protected]

Thanks, but I didnt hear from you and I found one elsewhere. I hope to get it installed and everything back together next week.

A question for the experts. I installed the governor last night but didn't have to time to get the oil pump and oil pan back on. My question is: The arm from the governor to the throttle control moves freely but the "output" arm from the governor to the carb linkage doesn't move freely or at all - should it?
I connected the rod to the carb and grasped it to move it but it didn't move. I havn't worked on these enough to remember whether I should be able to move the carb linkage rod back and forth.
When I had the governor off I checked everything inside, and all looked good including both arms worked freely and I lubed them up before installing it.

 

[vzuden]

I didn't hear from anyone on my question so I buttoned up the bottom end (reinstalled oil pump and oil pan) and tried to start it. No start - turns over good until the starter went out. I'm getting the starter rebuilt now.
So I had hooked up the governor output to the throttle linkage. The throttle linkage moves freely but when connected to the governor I can no longer move it. I am not sure if I should be able to or not.
I also had to move the adjustment about an inch from where it was originally to try to set it (full throttle at the operator lever and carb linkage full open).

Should I be able to move the throttle linkage back and forth once it is connected to the governor?

 

[DanMD]

(quoted from post at 02:59:40 06/08/22)
I didn't hear from anyone on my question so I buttoned up the bottom end (reinstalled oil pump and oil pan) and tried to start it. No start - turns over good until the starter went out. I'm getting the starter rebuilt now.
So I had hooked up the governor output to the throttle linkage. The throttle linkage moves freely but when connected to the governor I can no longer move it. I am not sure if I should be able to or not.
I also had to move the adjustment about an inch from where it was originally to try to set it (full throttle at the operator lever and carb linkage full open).

Should I be able to move the throttle linkage back and forth once it is connected to the governor?

You should be able to move the throttle back and forth with the motor off and everything hooked up through the governor.

 

[vzuden]

There is an update to this. I thought I would share in case anyone else runs into this. I found that I was not seating the governor fully. It was not engaging the drive to the distributor. When properly seated, the surface of the governor gear (facing the front of the tractor) is not flush or in line with the drive gear. It sits deeper so it is in contact with inner portion of the drive gear teeth. When properly engaged to the distributor the rotor and shaft will no longer freewheel as I found mine was doing. Also, now the output arm of the governor is no longer locked solid and has spring loaded movement when the throttle at the operator's lever is moved to full throttle position.