1985 JCB 1550 blowing diesel out of exhaust pipe

[NoProblem]

Here in Michigan we are having an unusual warm spell for February, so I thought I'd start the backhoe for the first time in about 3 months just to let it fast idle for an hour or two to charge the battery and get rid of any condensation or whatever.

It cranked right over as if it was just started yesterday and idled smooth, same as always - except diesel fuel is spraying out of the exhaust pipe and it's also leaking from somewhere under the engine all over the ground - I noticed this after about a minute and shut it right down, in that time, the puddle on the ground looks like about 1/2 gallon of diesel leaked out. It's parked in a grassy field and it's pretty muddy right now so I am not going to crawl under it to get a better look until the mud dries up.

It's been a great machine since I bought it about 27 years ago and it's strictly used around the farm.

Does anyone know what the problem could be? Here's a picture:

 

[thepumpguysc]

1st thing is to check the oil dip stick.. if its over filled to the top, either the mechanical lift pump [if equipped] failed & is getting fuel into the engine or the front seal in the injection pump has totally let go and is pumping diesel into the crank case..
DO NOT run it like that..
I would suggest a blown tip on the injector, but you say its running smooth.. and no black smoke.
the reason fuel is blowing out the exhaust is its getting on top of the pistons..
DO NOT run it like that..

 

[NoProblem]

Thank you for the quick reply, much appreciated! I won't run it like that, I shut it down soon as I noticed it and I will check the dip stick later and post back. Thanks!

 

[Delmer]

This will help remember to check the oil BEFORE starting a machine. If pumpguy's theory is right the level would have been way high, now it will be down closer to the full mark because so much has been dumped on the ground.

Was the liquid on the ground clear diesel, or blackened like motor oil? I'd hate to think how diluted the motor oil would have to be to LOOK like diesel. Unless maybe the oil didn't have any hours on it to build up any soot?

Does this have a flamethrower start aid on the intake manifold? Worth a look if the oil isn't diluted with diesel.

 

[NoProblem]

I found some old paperwork - it's a 1982 model year that I bought in 1985, not a 1985 model.

The fuel on the ground was pure diesel, the diesel has that purple dye they use for farm fuel and it looked and smelled like it was pure diesel. I'm 99% sure it was pure diesel that was spraying out of the exhaust too, the exhaust pipe is all wet and diesel has puddled on top of the valve cover.

I checked the oil, when I pulled the dip stick it was dripping purple diesel fuel from high up on the stick, well above the oil pan level, it's as if I pulled it out of a can of diesel, not oil. I wiped it off good with a paper towel and when I pulled the dip stick the second time and third time, seems like it was only diesel fuel and very low, like right at the bottom of the stick. Not sure what happened to the oil - I changed it about mid June and only had about 30 hours on that oil.

It doesn't have any start aid anywhere, never has - I only used to give it a slight shot of starter fluid when it was below about 45 degrees or so - above that and just turning the key would always start it right up.

Well, it sure was a mighty powerful machine. I traded in a Case 580CK for this one and the JCB could push better than twice what the Case could.

Not sure what I'm going to do with it, maybe trade it in on another or might get engine this one rebuilt when I get some $$$.

 

[thepumpguysc]

DONT GIVE UP.. Get me the #'s off the name plate on the pump and I'll walk you thru a 20.00 repair.!!!
+ 80.00 for the oil change.LOL

 

[NoProblem]

LOL
Awesome!
Except it's all mud and slop to get to it and all around it, and diesel fuel is mixed in with the slop around it and it's all over everything when I lift the hood.
I have the owner's manual that came with the machine, I also have the service manual for it - is this picture the lift pump you are talking about? If so, I will try to find the number that you need.

 

[thepumpguysc]

Those lift pumps are cheap.. The pic shows the cleanable filter screen.. The other portion w/ all the screws contains a rubber diaphragm.
They get holes in them.. You can buy a kit online w/ just alittle searching or just replace it.. They are easy to check..
remove it, put alittle air in the inlet side and block the outlet and squirting some soapy water on the plunger, see if it bubbles.
I was thinking it was the INJECTION PUMP that blew the front seal..
BUT check the lift pump 1st..
IF your going to take the lift pump apart to change the diaphragm, make a scratch mark on the 2 housings 1st.. inorder to get it clocked properly..

 

[NoProblem]

It's too sloppy around the machine to do anything right now - and of course, rain is heading this way to make matters more sloppy, so it'll be a while before I get back to this - but thank you very much for your help so far!

 

[NoProblem]

Hey thepumpguysc,
I finally got around to it and took that lift pump off. But first, I started the engine and it did the same thing it did in 5 moths ago, fuel pouring out of the PCV hose like crazy - so it did not fix itself, I had to check that first off lol!

So, I clamped off both fuel lines running to it with vise grips and started the engine again, with the lines pinched, the fuel coming out of the PCV was coming out drastically slower than with the lines not pinched, so I took the lift pump off and will take it to the JCB dealer, hopefully tomorrow (Monday) and see if they have one in stock, or if they can tell me for sure the pump is bad.

Thank you again for your help - I'll update this thread as breaking news happens

 

[Delmer]

DON'T RUN IT LIKE THAT.

You can test the lift pump by hooking it back up to the lines and pumping it by hand. Or leave it installed, just loosen the nuts enough to pull it off the block 1/4" and pump it by hand, it will be obvious if it's dripping that much diesel.

 

[NoProblem]

I only ran in for 4 or 5 seconds - hard to believe it even ran like that - and strong as usual too. But the pump is off now, so next time it starts it will have fresh oil and filter and a new pump. I gotta believe that the valves got a thorough cleaning with all that diesel, probably the whole oil pan is filled to the top with diesel too.

When I pump the outside lever, the one that's hooked up below the pump itself, fuel came gushing out of one of the ports pretty good - only a handful of pumps up and down drained the little tank.

Pumping the other lever that fits inside the engine didn't seem to do anything. The outside of the pump itself was all caked up with +30 years worth of grime, so at the moment, I squirted de-greaser and scrubbed, then squirted the outside and letting it sit for a bit to just clean the evil thing.

 

[thepumpguysc]

IF you have some compressed air around, hold your finger over the OUT pipe & put air in the IN pipe & submerge in a bucket of water.. or spray it w/ water & soap & look for bubbles..

 

[NoProblem]

$37.50 for new pump + $13.00 shipping, will arrive tomorrow. The guy agreed with you - he said I should have noticed fuel leaking out of it sooner because they usually go bad slowly - which is exactly what it did because for the last year or two, I left a trail of drips wherever I went, more if I was under a load.

 

[NoProblem]

Ok, well, all I can say is thank you again thepumpguysc and Delmer, I am very grateful!

I replaced the pump, replaced the oil and filter with fresh oil and filter and ran it about 15 minutes, till it got up to about 180 degrees or so, then replaced the oil and filter again. She is back to her old self - even a little better! I put it to work for about an hour or so and all went perfect!

I would have never thought the pump was the problem if you didn't tell me - thank you again! I was foreseeing some major engine work costing at least 50 times what I spent to fix this - which the total was - including, pump, shipping, oil and filters was about $108.00 and only a few hours labor!

Something to note:
When I drained the oil, it's color was dark like dirty oil, came out thin as water and smelled like pure diesel fuel, but, I always fill it with 2.5 to 2.6 gallons and that is about the same amount that came out. There might have been an extra quart or so, but I thought I was going to drain a few extra gallons at least, so not sure whats up with that.

I wish I would have checked the dip stick before I drained it, but I don't think it would have showed much, if any, over fill.

Thanks again!!

 

[thepumpguysc]

NOT BAD.. Only 5 months.. sounds like some of my projects..Lol
Shut the fuel OFF AT THE TANK in the future.. just gotta remember to turn it back ON when you go to use it..
Happy tractoring.. TPG

 

[Hobbytime]

this wasnt my problem( this time), but the amount of help and the knowledge given on this sight is fantastic.. so to all that do..a big thankyou!!!

 

[92U 3406]

This will help remember to check the oil BEFORE starting a machine. If pumpguy's theory is right the level would have been way high, now it will be down closer to the full mark because so much has been dumped on the ground.

Was the liquid on the ground clear diesel, or blackened like motor oil? I'd hate to think how diluted the motor oil would have to be to LOOK like diesel. Unless maybe the oil didn't have any hours on it to build up any soot?

Does this have a flamethrower start aid on the intake manifold? Worth a look if the oil isn't diluted with diesel.

About 3:1 lol.