Fuel in Oil. Leaking injector(s)?

Z

zsk7687

New member
Been away from diesel trucks for a while, and I'm not very familiar with the vp44, always had a 12v. Picked up a bone stock 99 2wd auto 3500 with 376k miles. Bought it just to haul hay and pull a cattle trailer. The truck had sat for about a year and a half before I bought it, but it fired right up and I drove it home. Topped off fluids, changed oil and filters (old oil was black as sin, no dilution). Previous owner said that the injection pump had been replaced years back, and they installed an in-tank lift pump.

This past weekend I had about 15k lbs behind it between trailer and hay. When I was getting close to home the oil pressure gauge would drop to zero when I would come to a complete stop and let the truck idle, but it would return to 40 when I stood on the brakes and gave it a lot throttle. Limped it home, got to reading and the first thread on another forum led me to checking the oil dipstick. Oil was 2 inches above full, very diluted with fuel. I fired the truck up and put a temp gun on the exhaust ports, #1 and #6 were running about 50 degrees cooler than the rest.

From what I've read on here and other forums, it sounds like I've got leaking injectors. But I just wanted to ask and see if there's anything else that I should check before I throw money at a new set.

Thanks in advance
 
Im by no means a vp44 expert, but we had a 2001 vp shop truck I used to drive some.

It became kinda hard to start 1st thing in the morning, and had a bad fuel knock when it was cold. replaced the injectors and fixed the issue with it.

I could see a common rail diluting the oil with fuel from bad injectors, but not a 12v or vp truck.

Is there any chance the injection pump is leaking fuel through the frt seal?
 
jasonc said:
Is there any chance the injection pump is leaking fuel through the frt seal?
Click to expand...

My buddy had mentioned something about a seal in the front of the injection pump being bad about going out. Would putting the truck under a heavy load make this more likely?

I'll pop the valve cover off and double check that all the fuel lines. Thanks for the ideas
 
I reread your post, I wouldn't put much faith in the factory oil pressure guage and sender. I beleive that yr it was more of a off/on type sender and the computer would send a signal to the guage to display and average.

only way to know for sure is a mechanical guage.

Does the truck run good? no abnormal smoke or fuel rattle?
 
Fuel dilution in a 24v is usually caused by a damaged/worn injector body O-ring, over pressurization of that area can also push fuel past the O-ring.
 
It’s been a while since I looked at the fuel plumbing, but did they run the return fuel back to the tank correctly when they switched to the in-tank lift pump? I’ve never done the switch myself so I’m not sure what gets changed.
 
Again yall, I don't know chit about vp 24v's, but I trolled in the experts for ya op, ha. Id take their advise.
 
Smokem said:
Fuel dilution in a 24v is usually caused by a damaged/worn injector body O-ring, over pressurization of that area can also push fuel past the O-ring.
Click to expand...

You were the man I was hoping to hear from. Would putting such a heavy load on the truck after it had sat for so long exacerbate a problem like that that was laying in wait? Prior to pulling that load this hadn't been an issue
 
It would be hard to say, but if the injectors were factory with that amount of mileage, I'd say they might be due for replacement.
 
You must log in or register to reply here.
Back
Top