Allis 5020 NO START

[mark777]

Hey Guys,

Frankly, I am a little embarrased as I pride myself on having the patience of an oyster when diagnosing common problems such as hard starting. But this one has me stumped!! I am appealing to a higher mechanical authority or to someone who has had similar problems.

Friend has a 1980 Allis Chalmers 5020 with the 2 cylinder Toyosha Diesel. And does not have much money. The tractor stalled over a year ago and would not start. It has been exposed to the elements, but does have a cap on the muffler. So I trailer'd it to my shop. The tractor has 626 original hours (4 digit hour meter) and will NOT start. Let me revise that statement. It will start if I tow it in high range, high gear. In fact it lites right off in about 15-20 feet but smokes pretty bad. Blow by from the breather cap and dip stick are fairly obvious.....but I have seen worse. It will start IF I run two 12V batteries in series (24V) but it still takes a while........and it will start up when the engine is nice and hot.

So Far I have: Installed new battery, battery cables and ends, new fuel, replaced fuel and return lines and fuel filter, cleaned seperator bowl, injector lines and cleaned out fuel tank, clean-new air filter....Oh, and two glow plugs @ $45.11 a pop.

This is what I think is happening: Because of stuck or broken rings, loose tolerances or excessive ware, it does not have enough inital engine compression to electric start...?? Maybe?? And because it starts right up when it is hot, this may indicate that the pistons, rings and cylinder walls have expanded enough to create adequate compression for electric starting...maybe?? The starter does not drag or indicate any problems with a fully charged battery...but the alternator is kaput. That I can fix later.

If anyone can give me any ideas of what to try next I would be grateful. I will even take far fetched, of the wall or slick tricks to try....I just hate to pull the head as I know the gentleman can't financially swing it.

Many thanks and regards, Mark

[Durwood]

How long have you let it run when it does start Mark? Would letting it sit and run for several hours help at all? Maybe loosing up the engine some more?
A stupid question i know, but it's all i got. :fing20:
Maybe there are some additives you can put in the motor when you get it running. There is a lot of stuff out there anymore to enhance engine performance.

Dur

[mark777]

Hey Dur,

I have run it about 15-20 minutes in the shop, allowing it to reach normal operating temperatures (5-6 times). I have also run it maybe 1/2 hour 45 minutes driving it on my property and up and down the block.....and back to the shop. I have probably a total of 3 hours run time (and 3 days straight of working on it).

I put healthy doses of Power Service in the original fuel and it made no noticeable difference. I tossed that fuel and put in new....with a ratio of 1 pint of MMO to 3 gallons of diesel. Also no noticeable difference. I also added maybe a 1/2 pint of MMO to the crankcase with a fresh oil change....nada, zip, nothing, zero results. Very frustrating.

Also were talking about a tractor that if someone wanted to give to you....you may reconsider the offer :). Anyway, it's the only tractor this guy's got and I wanted to help him if I am able.

Starting it and letting it run for a long time is something I hadn't considered, and might not be a bad idea. Thanks Dur. Mark

[Ohioplowboy]

if letting it run helps.... try gradually loading the engine.. sort of a re-break in period

put a load on it, but dont lug it.

[mark777]

if letting it run helps.... try gradually loading the engine.. sort of a re-break in period

put a load on it, but dont lug it.

Thanks, it has also been suggested from two other mechanic friends to use MMO in the fuel, let it run at PTO engine speed for a long duration and this will make the determination between stuck or broken piston rings....or even badly scarred cylinder walls. Very similar to Durwoods original response.

If, by some miracle, the engine has stuck rings, I will do exactly as you stated. Break it in with gradual loads at higher RPM's.

I hate to return the tractor in it's current condition with out trying everything I can think of.

Again, thanks guys for the feedback...Mark

[bear]

i've had good luck adding dexron atf to the oil and working the engine to free up stuck rings if you have a dyno thats the best way you can keep it at a steady load without lugging it down