chevygirl

iTrader: (69)

What would cause fuel to mix in with the engine oil? I have a tbi truck and the oil is high on the stick and it is light in color. I believe it smell like fuel on the oil dipstick. I watched the fuel injectors after the key is turned off and they are not dripping after it is cut off. Any idea? Mechanic said it is not milky in color so it is not coolant.

MikeGyver

iTrader: (5)

Do you let it idle a lot?

whitt1

I don't know what would cause it on TBI truck,but on earlier trucks with a mechanical fuel pump,the pump could rupture leaking fuel into the engine oil.The truck does need immediate attenton.

chevygirl

iTrader: (69)

It was at the dealer for 3 days and they said after looking at the oil that it was a funny color to the oil but he thought it was because the truck has not been drivin alot. But I did drive it until the cat. converter started messing up and is going to be replaced. The mechanic said he could find no reason for the converter to be messed up but maybe it was an internal coolant leak I had on the engine they took out. I have a new GM engine and the oil looks the same. The mechanic acted like it wan't anything to be worried about. He said something about condensation. I am worried about it before I replace the converter. I have been idling the truck alot because I have been working on it.

SBTork

iTrader: (5)

I've seen condensation on the oil fill cap on engines before but not on the dipstick. I had the intake gaskets on my '86 350 fail on me last winter, and there was a little bit of the coolant/oil mix on the very bottom of the dipstick, but your situation seems a little bit different.

jblack6527

Maybe its running really rich, and when its idling, some fuel is puddling up in the intake and then seeping past the intake gaskets? Just speculation, I have never heard of it, but im sure if im way off someone will correct me

Mangled03gmc

iTrader: (95)

What do you mean about smelling like fuel, oil usually smells a lil like fuel when you change it, it is just the nature of the beast. It could be do to a few bad rings and and blow by.

Kingpimp

iTrader: (1)

I always smell the oil on diesels that have been sitting for a while before I start them. I learned this tip a long time ago, but I think it was because unburned fuel would sit in the cylinder and leak past the rings, getting in the oil.

When I did smell diesel in the oil, we changed it immediately, and especially before starting it.

TurboGibbs

iTrader: (6)

If the injectors are not leaking down then the excessive idling is about the only thing that could do it. I have seen it before in vehicles that are used for small jobs here at my work and never get over 20 mph and very rarely warm up. After a month or more i've seen them 2-3qts over full and the oil light comes on due to low pressure from low viscosity. One particular truck only has 39k miles on it. A little bit of unburned gas will get into the oil on every engine but cruising at higher engine speeds and more heat, the gas will be evaportated out.
I would change the oil of course. Excessive gas in the oil will wear the rings out in no time due to lack of proper lubrication. This is known as "washing out the rings".

Blown02Sierra

i ran into the exact same situation on my '46. Granted, its a stroked 454 running 2 quad barrel carbs, it happened when i gave it too much fuel when starting. I'd say in your situation it's bad rings or running too rich. Change it no matter what though...