dumbfounded

[JDNPC]

Alright, I will lay it all out there and try just about anything from this point on. My 36" b was completely gone through 2 years ago. Ran sweet and smooth for the first 3 weeks. I gave it a workout infront of a pull binder. Got her back home, & the next day she went to running rough. So, I retorqued the head nuts thinking they may have loosened some on her first work out. Put it back together and still the same problem. So, to eliminate any of my own stupidity, sent the mag out, the carb out, put on a new manifold and head gasket, new solid wires and new terminals. She is timed right,rv2b mag has great solid blue spark, getting plenty of fuel and I"ll be danged, still hitting on the left side only. The right cylinder stays wet with a gassy-oily mixture 24 hrs a day. It does receive spark, but no fire in the hole. I can pull the #2 wire off the plug, jump the spark, pull the plug see the spark, but no bang in #2. I sprayed wd-40 around the manifold, head gasket, took the manifold off and checked for burn out in the dark with a flashlight. re-lashed valves numerous times, reset the mag a half dozen times,no slop in throttle shaft, through a few wrenches across the barn, taught my dog a few new phrases. I"m at my wits end. My head was checked,planned, new valves, seats, springs. What am I missing here?????

 

[Roger in Iowa]

Sticking valve. Check compression pressure.

 

[pbb]

Im like Roger check compresion. What is going on when the petcocks are open? Is there any gas being blowed out?If the valves are sticking it maybe blowing the gas out the exaust or the intake valve stuck blowing back in the intake.Every mechanic i have ever talked with and its in my manual it wont run rite if theres 10 lbs preasure diffrence in cylinders.I had a 2cyl motor with 120lbs on one and 20 lbs on the other.It done what you described it ran on one cyl and the other was wet.I hope this helps.

 

[RandyB(MI)]

Gotta agree with Roger. It takes fuel , air and spark to make fire. You seem to have all of them. But it takes compression to make power out of the fire. Seems like the only thing you failed to mention in your post. Could be stuck valve (and maybe only when hot) or a worn out cam lobe. (if intake don't open you cant get air to compress) or a bent pushrod (should have evident when lashing valve clearance)Check comp and if low make a fitting for spark plug hole to hook up air compressor to. Put that piston at tdc compression stroke.Tractor in gear and pully brake on. Hook up air and listen to where it is leaking by. Intake or exhaust pipe---stuck open or burned valve. Crank case---broke piston or rings. No leak---intake valve not opening (cam or pushrod)Post back with findings.Just for giggles switch spark plugs around. (not wires---just plugs)

 

[EScottUtz]

You might try a different plug in that cylinder. It's uncommon, but plugs can fire laying on the manifold and won't fire under compression. I also agree with the other fellah. You should check the compression. It would give you a better picture of what's going on.

 

[Kurt_JDB]

JDNPC,

I have a 1937 B that is behaving just like your 36 B, except with mine the problem is in number 1 cylinder. I have just rebuilt it, went all through the head, sleeved the block, new rings, rebuilt the oil pump, governor, carb and mag. adjusted all the bearings etc, etc.

It ran great for the first hour, and then started running rough. Left side plug fouls, and only seems to hit every other time. Oily/carbon mix coating the cylinder walls. My oil is fine doesn"t seem to burn or loose any, no water in the oil either. No pool of water in the bore, so I don"t think the head gasket is leaking.

I have also checked the compression, 60 each side, rechecked the valve lash, torque on the head bolts etc. and put new screens in the filter bowl and in the carb fuel strainer.

Today it was good and hot around here so I decided to see how hot I could get this B to run. I have never got the gauge over 170. I don"t have shutters so I cut a piece of cardboard to go over the radiator. I don"t have a plow to hook up because I live in the city, but I do have hills. I ran up and down some hills until I got the gauge up to about 200. That little B just pulled right up those hills and fired off on both cylinders. Had a crowd gather to watch.

Bottom line was when I got back home and pulled the number one plug, it looked pretty good. Still a little oil on the plug body, but the electrode and porcelain were clean. Runs smoother, but still not a great idle

I am now thinking the rings have not had the opportunity to seat properly on number one, and I"m getting some crankcase oil by the rings. I think putting on a dyno or a plow might be what it needs. Just might need to be worked hard.

Maybe this is what your 36 B needs too.

Sure would like to stay in touch about this.

Kurt

 

[gtx1967jewison]

wow! lol it sounds like a simple ignition problem to me. the oily/carbon "mixture" as u call it is simply unburned gas. you need to get it up to at least 190 temp & pull it hard to break it in. a binder is not a load.

 

[Mike M]

I'm not familar with the inards of that style of mag. But being it is an old obsolete model for which may have VERY limited parts available it could very well have an internal problem where it sparks out the wire fine but under a load it fires inside of itself.

I'd start by putting a known good mag on it. Find a wico XH with a long lug inpulse coupling and bolt it on.

 

[Anonymous-0]

Sounds like you did everything but replace the Spark Plugs.

 

[Machinery-Man]

Had a 50 B would do the same thing. The manifold design along with engine design allows more fuel to the lead cylinder #1. Also if you are still using the all fuel jets in carb you're getting more (no unleaded-hi temp operating fuel) than your ignition can handle. I had the same problem with all the 2 cylinders till I upped the ignition with electronic...went up to around 35,000-40,000 volts. It would then fire the unleaded and keep the plugs clear. If you start and stop the ole 2 cylinders a few times you will kill the plugs if you're running original ignition. A test I used to show people about the electronic is I would wash or flood a 520, crapt would be coming out the exhaust, I would then choke off and the electronic would fire and clear the plugs...try that on standard. I would take the mag and have it beefed up as hi and possible, reject the carb with a gas main jet, then carry a pocketfull of hotter plugs....definity no champions

 

[Greenday]

Had the same problem. Ended up being weak compression!

 

[schrade]

Brother in laws 60 had a simular problem run great driving down the road and at idle but put the plow in the groun and 5 ft or so and die Put in new plugs and plowed for hours. wounldn't belived it if I didn't see it

 

[DONMYEIL]

I made a plate to bolt on to the intake manifold. Add air pressure, this will eliminate manifold, and valves .Open intake valves one at a time to eliminate piston rings and leaking head gasket.

 

[JDNPC]

both cylinders are at 60 lbs. Odd how both are that low. I guess i"ll pull the pistons tonight or in the morning and see what the rings look like. they were n.o.s. when installed. I didn"t hear any leak past the rings when i pumped it up on both sides. I swapped the plugs with new and known good ones. I even pulled the cam gear cover to double check the timing marks.No bent push rods, no stuck valves, no broken springs. I will drop the valves as well to check the valve seats to make sure they are staying put. I"ll report back in the AM when I find something worth repeating.... thanks fellas.....

 

[trustyt]

Hi, that RV2B mag has to be timed correct. You may be hitting on the LH from the terminal that is designed for the RH and firing the right plug in the exhaust stroke from the LH terminal. Those RV2B's are not like a Wico that hits every other snap. They only hit once in 360, and back to back, so you have to have them so the left & right hits in sequence, and the plug wires hooked up in the right sequence. I am telling you this from having had it happen to me years ago, and you do not forget those type of lessons. You may be timed and hooked up correctly, but it is worth ensuring so. You could also put a Wico mag on the B timed to the left, and see what I mean, as a test. I'll bet it is RV2B mag timing. Good luck, Ted.

 

[Kurt_JDB]

I think 60 pounds is exactly right. The unstyled B tractors had a low compression ratio of 3.9 to 1.

60 pounds is exactly what my "37 B reads.

Kurt

 

[teddy52food]

I think you nailed it. Also I was talking to a mag repair man at a show last fall & he said they like to put the rv mag on for show when the tractor is stopped, then put on a Wico X to run them in the parade. He called the rv's a rattletrap.

 

[LarrySTN]

Have you installed new plugs? Are you using wire core or carbon core wires? Make sure your wires are wire core. 60 lbs on both cylinders indicate that rings are NOT the problem. Don't be hastey to tear the engine down.

 

[JDNPC]

Well, I can honestly say a years worth of on and off messing around and listening to all of the suggestions here, paid off. I won't name names of the company who just bench tested my rv2 mag and said it was ok, because honestly I think it was a broken winding in the coil causing an intermittent spark, and those are hard to track down I'm sure. So off to the pro's it will go this fall for a full rebuild. After the fifth down to the pistons tear down, my old school buddy said put a good mag on her, so I did
and that solved the problem instantly. I don't normally have an extra mag laying around, but from here on, there will be. I cannot thank you all enough for all of the suggestions and advice. It is because of the knowledge and common courtesy that I keep returning to this site. !!!! thanks again and keep it green !!!