AC5020 NO START

[mark777]

Hello and help if you can??

A friend has ask me to help with his Allis Chalmers 5020 that won't start....and that is an understatement. A little history indicates that it stalled outside, in the elements and sat for a year. but does have an exhaust cap on the muffler.

Since I have trailered it here, I have replaced the battery, both cables, cleaned all contacts and checked out the electrical system. Bad alternator, but shouldn't stop it from starting. New fuel, fuel lines, filter and tank cleaned out. New glow plugs, and injector lines cleaned out.

This is a Toyosha 2 cylinder engine. It WILL start if I tow it 10 feet in high gear, high range. It smokes pretty bad....lots of blow by from breather and dip stick. It will start when the engine is good and hot, and it will start if I jump it with two batteries in series (24V). But if the engine is cold, cool or even warm, it will NOT start.

Is it possible that ring ware, stuck or broken rings or very low compression is preventing it from electric start, but towing it is enough to start it? And relative to that, is it possible that when the engine is hot enough the pistons, cylinder walls and rings have expanded enough to compensate for loose tolerances and give me just enough compression to electric start?

One more thing....when the engine is warmed up, it smokes much less, but never completely stops.

If any one has any suggestions, slick tricks or far fetched ideas, I am willing to try all at this point. I hate to put ether to this engine and almost never do, but the situation is becoming drastic as I am running out of ideas and options.

Thank you for any and all feedback.

Regards, Mark

 

[GeneD14]

I don't know the answer but I do know where you can find it: www.allischalmers.com in the discussion forum area. Lots of dealers, mechanics, restorers, collectors for AC tractors. Good Luck!

 

[mark777]

GeneD14,

Thank's, I have just visited that site per your information and searched their archives...nothing. Next, I will post a hard start thread, and again thank you.

Mark

 

[Soundguy]

Won't start on electric starter.. but will start with starter spinning real fast ( 24v ).. or will pull start.. indicitive of a real worn engine. Gas jobs work the same way.. that's why lots of people convert a hard starting 6v tractor to 12v.. 12v makes a worn out 6v starter spin faster.. also makes a low compression engine start easier.

If you are getting lots of bottom end blowby.. you are loosing compression.. diesels absolutely need compression to start..

Could have been a fuel issue making it stall originally.. then rings siezed up while setting.. then broke on the restart.. hard to say.

I'd change the oil if you havn't already, and run it with some MMO in the diesel .. after anhour or two of running.. if it doesn't get better.. Id think it is a broken ring vs stuck ring issue.

Some diesels like that can get by another year on ether.. but ya gotta be extra carefull about ether on diesels... makes for loose head bolts /forums/images/graemlins/grin.gif

Pulling head will be tell-tale.

Soundguy

 

[mark777]

Thanks Soundguy,

I kind of new this was headed in that direction...but being unfamiliar with that model, was hoping for a miracle solution. Funny too, I have a fresh quart of MMO sitting on the hood while debating this as my next step.

Mark

 

[EquipmentJunkie]

Your 5020 Allis was also the same basic tractor as the Massey Ferguson 210. You may wish to post a question under that forum as well. The MF guys may provide some wisdom.

I can't provide much insight to your problem, but did have one thought:
- Have you checked or changed the glow plugs?

The issue that you have sounds to be beyond glow plugs, but glow plugs seemed to be more essential in years past. Some of the early Japanese diesels needed to have the glow plugs cycled even after running the tractor for an hour on a 85-degree day. Twenty-five years ago, I remember my father getting frustrated by a then-new Kubota L245 that would not start at any temperature unless the glow plugs were cycled.

 

[mark777]

Yep, new glow plugs....and at $45.11 each I was hoping for a significant difference....but nothing. On this model it also has the lamp elemnet which lights up - looks like a cigarette lighter element on the dash. Everything is working perfectly on that end.

Thanks for the advice...I'll post on the MF and see if anyone has any clues.

Mark

 

[slowrev]

I think I would go with Soundguy's diagnosis. Sounds like a compression problem.
Ben

 

[js5020]

My 5020 is not a hard starter at all, except when I change the fuel filter, then it can be a bear to get running again. With temps at 70 or above I don't need the glows. I'd have to agree with a lack of compression, unless the starter is dragging, mine does require a good spin, I'd also check the amp draw on that starter. As far as the smoking, from new mine will put some black out at first start, and will have slight smoke, hardly noticeable when warm, done it for 800 hrs.

 

[mark777]

Thanks everyone.

There's just no fixing it from the outside. I'm in the process of pulling the head right now. I'll give an update on what is really happening.

Regards, Mark