Runaway Engine

[benwelder]

OK, giving this one last shot. Posted this in the Brand-specific-section with no results. If nothing here, I'll stop bugging you guys....

Hi all,

Been reading here for quite a while. My parents just recently bought a 40 acre farm in Maine growing organic produce. It came with haying a equipment (for the cows) and an old International 574. That tractor has a hard time running the mower without overheating.

So they bought a used Case 1690. Nice piece of equipment, 4wd, FEL, etc... Had it about 7 months now. It was great in the winter and the snow. Nothing could stop it.

Now the issues:

Steering: It's been having this steering problem. Some of the time it steers fine, little effort, as power steering should. But it will intermittently, have arm-strong-steering like you have no power steering. It has always been leaking some kind of oil from under the dash, and the guy they bought it from said that he just replaced the power-steering pump. So, tore apart the dash and pulled the steering motor. Took the motor completely apart, didn't seem to be anything obviously wrong, so got a seal kit and put it back together, and installed it in the tractor.

Now the fun stuff...

After putting the steering motor back in, didn't reassemble everything in case it had to come out again, started the tractor up and it immediately rev'd to full throttle, started throwing the random spark out the exhaust pipe etc... thought "oh well, no problem just pull the off switch"

Pulled the fuel cut-off switch and nothing happened... thought a couple of other choice things and then stalled it out with the clutch.

So now two more problems:

1. Fuel shut off doesn't have any effect.

2. Throttle is wide-open.

Any help would be great.

Checked obvious stuff. The linkage to the fuel shut-off is worn and not turning it reliably. So took this off and manually tried it and no effect. The throttle works, doesn't seem to be stuck...

Kind of baffled, and not much experience with diesel engines.

Thanks,

-BenWelder

 

[tessiers]

I have heard of this before mostly in detroit engines. Can't recall the exact problem but it has to do with oil leaking into the pistons, gaskets maybe? After it burns enough oil it will seize the engine (not enough oil left to lubricate) The only way to stop it is stall the engine. I will try to contact my mechanic and see if he has more details.

 

[Eagleview]

If i read this correctly , you pulled the linkage off the pump and it seems to work as it should ? And the stop lever also works as it should at the pump ? And the loose dash is not pulling on the linkage ? Or if fitted with a hand throttle , it has not been bumped ?

I am assuming that the engine only went as far as the governor would allow it , so it is still running on Diesel and not sucking oil from somewhere and running out of control .

If none of the above , I would have a guess that it is fitted with a CAV pump and when the dash was lowered , the linkage was put under strain and damage was done to the internal pump linkage and it is at WOT .

 

[Stimw]

I would guess that something isn't hooked back up correctly and the power steering fluid is getting into the intake some how.??????
Check all fluids and see if something is below normal.
If it's running off of something other than fuel the shut-offs won't work.

 

[benwelder]

Thanks for the help guys!

Yes, we checked all the linkages, these are all working as they should, hand throttle, foot throttle, fuel shut-off. All these linkages are working correctly, they just have no effect on how the tractor runs. And the dash is not pulling on anything.

Yes, the engine only went as far as it was governed. It was at wide-open-throttle and blowing some sparks out the exhaust pipe.

I'll check the fluids.

Someone also suggested that the injector pump is shot, something about it's seals leaking by fuel.... any thoughts on this?

 

[Midsouth]

Yes it very well could be the injector pump itself. We had a 3020 John Deere do that several years ago. Just like yours except we had not done any recent work on it. Went to go to work one morning started it up set throttle and about 1/4 speed. Got off to do something and it went wide open. Had to choke it off as like yours throttle had no effect on it.

 

[Eagleview]

Someone also suggested that the injector pump is shot, something about it's seals leaking by fuel.... any thoughts on this?

It was working OK before the steering was worked on wasn't it ? Something has happened in the mean time . And if the governor is working , it is running on Diesel .

 

[benwelder]

Yeah, that's the part that doesn't make sense. Everything was working fine before I started trying to fix the steering.

All I did, was remove the dash enough to get at the steering motor, took that out, put it back in, and now it does this... maybe it's all a coincidence. It doesn't seem like anything I touched should have any effect on the engine.

 

[patrick_g]

The engine must have air to run. It can get fuel from oil leaking past rings or valve guides or... and shutting off the normal fuel supply doesn't help because it may be running on a different supply, leaking oil.

It can't run without air. A heavy large rag or towel or your hand over the air intake will stop it RIGHT NOW. Emphasis on large rag as a small one might find its way to an intake valve.


Shutting off its air is much less destructive than stalling it.

Pat

 

[wushaw]

I would suggest to get another pair of eyes on the subject, it helps in troubleshooting a problem when one runs out of ideas.
We can suggest everything feasable but sometimes it just doesn't help.