Allis WD Running Rough - Update 3

Well guys, I got the carb for that Allis WD all cleaned up and put in a new rebuild kit. (The photo enclosed is after I cleaned it, and cleaned the OLD parts). There was a lot of rust scale in the bowl. There must have been some water in it for some time at one point. Seems to be running really strong, but still has a pop/misfire coming from what I believe to be #1 exhaust valve/port. I'm thinking this tractor is good for an overall once-over. Head work, and probably a top end with 90-95 PSI in the cylinders (due to what I have gathered from you all).

Tractor does not smoke at all, though. I told him to run non-oxy gas in it and see how it pans out. For now, it seems to be running pretty good. (I apologize for the poor video quality - cell phone was all we had at the time).

Maybe a manifold leak as well? - but I can't seem to get any change in RPM when spraying it down with Carb Cleaner and propane near all manifold connections.

Allis WD Update Carb Rebuild

Fantastic! Sounds like you have its future figured out!

Have the checked the tappet clearance?? A simple valve that need to be adjusted could cause it to miss a bit and back fire a bit out the exhaust

Old,

Yes, I did check the valve tappet clearance. I went through a number of things on my first trip out there. In my last video I talked about everything I went over. Valve tappets, points polished and reset. Replaced the plugs. Went through a number of 'regular maintenance' items... Still didn't get the tractor to run very well (lot's of popping/carb and governor hunting/surging), so I pulled the carb and did a full rebuild. Everything seems real good now except for that slight misfire every now and then.

A link to the previous video (skip ahead to about 7:30):
Allis WD Troublshooting first video

I'm on dial up so I cannot watch a video just a 5 minute one takes an hour to down load o watch. Have you tried the NGK3112 plugs???

Just a thought spray around the head gasket and plugs I had a leak around the plugs on mine.
Byron

That is a good idea - I never thought of spraying the seam of the block and head, as well as the spark plugs. Next time I am up there I will do that.

I did recommend he pick up some NGK plugs if he could find them (he is in a small town area), but he ended up picking up a new set of Autolite 295's instead. It seems to be running pretty well. One of the major factors I believe that was contributing to the 'hunting' of the governor and carb was the fact that the carb float was set extremely low. My guess is it would run itself too low of fuel in the bowl to adequately maintain higher RPM's. I would say it was almost 1/2" instead of what the recommended 1/4" is. I readjusted that as well during the carb rebuild.

Here is what I did so far:
- Compression test. Yielded 90-95 PSI on all 4 cylinders. Low to moderate, but the tractor does not smoke.
- Complete carburetor cleaning and rebuild/fine tuned/low idle set
- Points cleaned/polished & re-gapped
- Valves all adjusted to factory spec
- Replaced valve cover gasket due to severe dry rot/leaking
- Replaced old/broken wire from Dist. + to Coil +
- Checked manifold/carburetor connections for leaks with both carburetor cleaner (aerosol), and propane. No change in RPM.

There may have been more, but this is all I can think of right now. The tractor runs good except for the mild pop/cough through what seems to be the #1 exhaust port. The longer I ran it, the better it seemed to run.

I had trouble with my 1949 Farmall cub it was a lot like what you are having it turned out to be the spark plug wire to that cylinder I changed the wire and it has run fine since then. Randy

Also a good idea. I'll see what he wants to do. Thankfully plug wires are pretty inexpensive.

Bet you will find it when you pull the head when he decides to do a rebuild. Did you put your hand over the breather tube to see what kind of blow by you were getting. Without smoke and only normal blow by the lower compression is probly valves being bounded into the seats/head.

I have pictures of where the valves had beat into the head but still didn't show burn on the valve. I can't seem to find a picture that is real clear.



I did find a picture of core shift when I was installing seats. It broke thru a tiny pin hole at the seat depth and I had to bore it out and make an insert to make the repair before installing the seat.

Those auto lite 295 plugs sound way to cool for that engine. At the very least he need auto lite 437 plugs but the NGK3112 hands down will be 10 times better then the 437 plugs are. As for getting them if he has an auto parts store in his town he can get them

Be sure he has true wire plug wires not the carbon core stuff made for cars. My self I use the O'Reilly's Omni spark plug wires part #9994

Mine was missing out and backfiring, and it turned out to be a cheap, rusted, toggle switch that was put in by someone instead of a key switch.

Although my WC with a WD engine sounded good. Ran good, I noticed it was not banging on all four cylinders. Paint was not burning off of #1 cyl exaust manifold. Double checked with a laser temp gun. Confirmed not fireing. The valve springs were weak. Some were an inch shorter than the replacement valves. Even though I was reading 95 on the comp check before. Eng vacuum was pulling the valves open. Just a thought.

I watched both of your videos...I wish I could edit and put together clips like you do In the last video it runs really quite good. I relate to the popping and the hot port description. Earlier this year I had some of same as we started up a 1947 A-C with a 201 cu. in. engine like you're working on. The issue with that became apparent quite quickly that some of the valves would stick and not close all the way. It's a little tell tale when they run more perfectly cold and then after warming up valve to guide clearances tighten up and there's not enough force in the spring to fully close one or several valves...usually exhaust valves. We took the valve cover off and manually pried and tapped the valves and springs while using good quality penetrating oil on the valves at the top of the guides. It was only a matter of minutes of doing this that symptoms disappeared and we had a good running engine. A leaky exhaust valve works like a torch on the port side. You mentioned that you noticed it already starting to run better...with clean engine oil and running w/o being parked too long (like weeks or months) will probably bring it back to normal. If it were mine I would take the valve cover off, spray the top of the valve guides, tap the top of the valves with a hammer for a bit of vibration. Except that you'll have oil spraying all over the place ...but letting the engine run while spraying the guides is very effective.