MF-202 Delco Distributor

[Stan Coryell]

I did some maintenance on my 202 tractor today on account of the 65 degrees and rain. I figured I'd pull the distributor, clean it up, and do a general tune up. I took the plate off to have a look at the advance. Am I missing the weights and retainer plate? The advance is also different from the parts book. My distributor is a Delco 1112557. The first two pictures are what I have and what I should have. The third picture is a Delco 1112643 Distributor. This appears to be the cam I have. The plate in mine does not seem to be tapped for the retainer plate. Thoughts? Can anyone tell me what the end play should be? Mine is .028 measured with feelers. I would think it would be less than .010. There doesn't seem to be any axial play. Any thoughts or advice would be appreciated.

Happy New Year
Thanks in advance,
Stan

 

[Jim.ME]

That looks like someone had distributor problems and did a field fix (by removing advance components) to keep going. There is visible wear on the shaft and weight plate, the weights are missing, as is the retainer plate. I would stick it back together so I could keep running while finding a complete, proper distributor.

 

[Dieseltech]

You have parts missing, for sure..

 

[Stan Coryell]

Thanks. I found one on Ebay. Any ideas on what the end play should be?

 

[Jim.ME]

.010" or less would be good, but I don't think .050" would make a noticeable difference on a tractor. It is simple to put a shim between the gear and body on a cast iron Delco distributor if needed. The aluminum body ones had shims with a tab that mated with a slot in the distributor body, so the shim didn't try and wear the aluminum body.

 

[Stan Coryell]

Thanks Jim. The advance spring pins are
hitting the breaker plate. Not by much.
The plate was also bent. I'll shim the
shaft to .010. I plan on putting the gear
back on with a roll pin. Do you see any
trouble with that?

Thanks again

 

[Jim.ME]

Likely ok short term but a solid pin, as original, would be better. A spiral pin would be better than a plain roll pin or try for a roll pin inside a roll pin.

 

[Usedtobeiowadave]

Are there metal shavings in the bottom of the distributor housing? if you make your repairs and it eats another one, you may run into what I did years ago: gear end broken off the camshaft. You wouldn't think it could possibly run in such a state. It will, but transmits the resulting vibration to the distributor and chews it up. ended up being the beginning of a total engine overhaul for me, but it's given me 17 years of faithful service since. Good luck

 

[Stan Coryell]

Thanks. I didn't find any metal shavings. I suspect the bushings went and ate the original shaft. According to the parts breakdown, the shaft in there is out of a Delco 1112-643. The advance is different. All just a guess. I found two distributors on Ebay. Hopefully with three I'll have enough parts to make one.

Out of curiosity what caused your catastrophic failure?

Stan

 

[Usedtobeiowadave]

Mine was sold to me with a brand new distributor on it circa 2004. Ran great for a short while then started sputtering. Got into the distro and found missing components similar to yours. The remnants (metal dust) of them covered the bottom of the distro. Put a new distro on it, ran fine for while, then more sputtering: ate the new distro. Put my hand on the distro while it was still running and could feel the excessive vibration. I discovered this site and the Massey board and asked for guidance. An old timer named Big Dean, rest his soul, used to be one of the heavy hitters on this Massey board. Had me check a few things and then told me the end of the cam driven by the timing belt was probably broken off. Split the tractor, pulled the timing cover, the gear end of the cam fell out. Still for the life of me can't understand why it would run at all in that condition. Only thing I can figure is that it still friction fit in place enough to run, but transmitted a lot of vibration through to the distro. Ended up doing a complete tear down and rebuild with lots of help from this site and darn near new everything but block, crank, and flywheel. Turned out to be $ and time well spent as it still runs like clock and is a tractor that serves my needs well. Hope yours is a lot simpler solution.

 

[Stan Coryell]

Thanks. I don't think I have any issues that severe. Someone worked on the distributor a long time ago. Enough to get it to run anyway. It runs well. Compression is 135# cold. It starts right up. I'll be interested to see how much difference the advance makes. It has developed a small intake leak, which I'll get to.

I'm currently chasing oil leaks. The Rear Main Seal leaks. The loader needs a lift cylinder re-chrome, the spool replaced, and I just found a weld leaking on the back of the frame (hydraulic tank). It looks like it was repaired twice. The 3 point also needs some new parts. It's getting there, but iIt's done a lot of work for me so far.

 

[Usedtobeiowadave]

I think they're worth the work, never really seen anything I'd like to replace it with. Mine has the factory MF 200 loader and 3PT/PTO. Parts are pretty easy to come by.

 

[Stan Coryell]

My distributors showed up today. I'm still curious about the end play. If anyone has a guess, I'd love to hear it. I'm gonna go with. 005-.008.

Another question. If the distributor turns counterclockwise, the advance would also turn counterclockwise, correct?

Thanks,
Stan

 

[Jim.ME]

Your mechanical advance turns the same direction as the distributor rotation, as it is moving the cam. A vacuum advance moves in the opposite direction of the shaft rotation, as it is moving the breaker plate.

 

[brooktre]

I couldn't find anything definitive on distributor end play for a Z134.

I did find that on a Z129 the Ferguson Shop Manual for TO-30s says the end play should not exceed 0.010 (and this was for a Delco-Remy distributor).

I've also read where too tight can chew things up so you're probably good with 0.005 - 0.008.

This post was edited by brooktre on 01/06/2022 at 08:36 am.

 

[Stan Coryell]

(quoted from post at 07:46:20 01/06/22)
Your mechanical advance turns the same direction as the distributor rotation, as it is moving the cam. A vacuum advance moves in the opposite direction of the shaft rotation, as it is moving the breaker plate.

Thanks, that is what I figured. I just wanted to double check. I have found a good bit of backwards stuff so far on my tractor.

 

[Stan Coryell]

Thanks, I took a look at my "new" parts last night. the bottom thrust washer seems to cut into the shaft on all three of mine. I measured somewhere around .105 total end play. I found .048 shims on McMaster. I'm going to run with two of those for now and see what happens.

 

[Stan Coryell]

Just wanted to follow up on my distributor and thank everyone for their help.

Out of the two I picked up from Ebay and mine I was able to put mine back to proper operation. Advance is now working. I did learn that Delco used two different diameter shafts for the advance cam. I've also gathered the springs have nothing to do with total advance. Total advance is determined by the movement allowed by the slotted holes in the plate attached to the distributor plate. The springs change the rate of advancement. Did I get that right? Last, the plate attached to the distributor shaft has a number stamped in it, "724". 24 is the degrees of advance. 24 plus the base of 6 produces 30 BTDC. I timed my tractor, 6 BTDC @ 450 RPM and 31 BTDC @ 2000 RPM. The book calls 30 for plus or minus 2 @ 2000 RPM.

If anyone needs any Delco parts let me know. I probably have enough to build another one.

Stan