Oil thin and drippy

[Dasgog]

Hello

So 3 months ago I noticed low oil pressure and oil was really thin. I can say for sure it is not mixing with Radiator but am only somewhat certain not mixing with fuel. I say this cause I don’t smell any fuel but that really isn’t an indicator.
So 3 months ago I changed it and it was thick and oil pressure at startup/idle and driving was beautiful. Now I noticed oil pressure getting low again and at idle it’s like 10lbs. I checked oil and it’s thin as hell.

So I assume the worst case is always the case or else it wouldn't be an issue therefore I think fuel is mixing in. What are some “easier” reasons and fixes to this?
I just hope it’s something someone non mechanically inclined can fix .

 

[Mullaney]

Hello

So 3 months ago I noticed low oil pressure and oil was really thin. I can say for sure it is not mixing with Radiator but am only somewhat certain not mixing with fuel. I say this cause I don’t smell any fuel but that really isn’t an indicator.
So 3 months ago I changed it and it was thick and oil pressure at startup/idle and driving was beautiful. Now I noticed oil pressure getting low again and at idle it’s like 10lbs. I checked oil and it’s thin as hell.

So I assume the worst case is always the case or else it wouldn't be an issue therefore I think fuel is mixing in. What are some “easier” reasons and fixes to this?
I just hope it’s something someone non mechanically inclined can fix .

.
You could order a sample bottle from a company and have your motor oil analysed. There are companies that do that sort of thing for a living. They should be able to tell you what is in there besides oil.

Search here for " Blackstone Laboratories" as one possible option. (No, I don't work there)

Guessing the warmer weather has nothing to do with the oil being thinner?

 

[Dasgog]

Hello.

Yeah I mean it could very well be that. I just find it odd how thin it is just 3 months later (maybe 50 miles on new oil).
I will look into that of which you mentioned I suppose that’s the legit answer as it’ll tell me what is in the Oil.
Another thing I noticed is like.. knocking when it’s cold and then goes away when warm. I assumed this was cause of the oil being thin.
I’ve had the tuck for 3 years and have some 0 engine work. Before that, who knows.
In the meantime what is usually the cause of the fuel in the oil? Is it just a head gasket replacement?

 

[SCSG-G4]

Is the FDC bypassed? That is a great cause of fuel getting into the oil. There are some other places on the IP that can leak fuel into the oil. Search for "Bypass Fuel Density Compensator" here on the site.

 

[wheelspinner]

Is the FDC bypassed? That is a great cause of fuel getting into the oil. There are some other places on the IP that can leak fuel into the oil. Search for "Bypass Fuel Density Compensator" here on the site.

This. You are “making oil”

 

[Dasgog]

Is the FDC bypassed? That is a great cause of fuel getting into the oil. There are some other places on the IP that can leak fuel into the oil. Search for "Bypass Fuel Density Compensator" here on the site.

morning!

great suggestion but yes it is bypassed. Previous owner had done that...
A little sun question here but hope main question doesn’t lose focus.... does bypassing FDC make it NOT Multifuel anymore? And also if the fdc were rebuilt is it beneficial to reconnect it? Just a side question there.

 

[NY Tom]

Bypassing the FDC will allow it to use other permissible fuels but make less or more power doing it. FDC adjusted for different fuel densities and compensated for this.

You could have leaking O-Rings under the Hydraulic Head, leaking booster pump seals or a leaking cold start fuel injector. If FDC is bypassed correctly that takes it out of the equation.

Lots of threads here about these problem areas.

 

[G744]

What oil are you using?

DDG

 

[Dasgog]

What oil are you using?

DDG

Rotella Straight 40.

 

[SCSG-G4]

Rotella Straight 40.

Most of us use Rotella T4 15W-40, other use the Mobil version.

 

[NY Tom]

Running straight 30W Mobil myself. Not thin.

I forgot to ask but is the oil level going up? Is it keeping pace with some nice leaks?

 

[Dasgog]

Running straight 30W Mobil myself. Not thin.

I forgot to ask but is the oil level going up? Is it keeping pace with some nice leaks?

I can’t say it’s “raising” in level it’s still at the full mark. Just figured it’s be lower.

 

[frank8003]

Change all the filters and all the lube oil and watch......
What you just said that what is NOW in that engine don't belong in there.
Maybe it is residual. It is only 140 bucks to change the oil and all the filters.
Don't guess, Your engine is now expensive. You can get a rebuilt one, while
they last for $6500 then You have to change it out.
Proper lube oil is a necessity.
There is 5 ways to destroy the lube oil in a multifuel, make it six, if one considers
NOT getting the puppy hot enough to burn off the nasties.

 

[Dasgog]

Change all the filters and all the lube oil and watch......
What you just said that what is NOW in that engine don't belong in there.
Maybe it is residual. It is only 140 bucks to change the oil and all the filters.
Don't guess, Your engine is now expensive. You can get a rebuilt one, while
they last for $6500 then You have to change it out.
Proper lube oil is a necessity.
There is 5 ways to destroy the lube oil in a multifuel, make it six, if one considers
NOT getting the puppy hot enough to burn off the nasties.

Don’t mind my stupidly but I am confused. You are referring to my Straight 40 being improper? I have 0 issues getting new filters and oil... Would what was mentioned earlier, 15w40, be the correct?
sorry when I hear lube oil I’m thinking gears (transmission, differential, transfer case.)

 

[frank8003]

Use your heat gun on the oil filters and get that puppy hot, above 190F° of the engine lube oil.
Change the oil and drive it loaded up.

Your engine. Use whatever You want but Straight 40 winter might not belong in there.

Change the oil and then watch. Could be fuel, could be antifreeze, could be lots of nasties in there.
Get rid of it and DO NOT put that drain oil in the fuel tank.
There is almost no way to get the soot out of it.

Yes, You can burn up the drained lube oil and yes,
You can put in a new hydraulic head, but sorry they not available.

 

[Dasgog]

Use your heat gun on the oil filters and get that puppy hot, above 190F° of the engine lube oil.
Change the oil and drive it loaded up.

Your engine. Use whatever You want but Straight 40 winter might not belong in there.

Change the oil and then watch. Could be fuel, could be antifreeze, could be lots of nasties in there.
Get rid of it and DO NOT put that drain oil in the fuel tank.
There is almost no way to get the soot out of it.

Yes, You can burn up the drained lube oil and yes,
You can put in a new hydraulic head, but sorry they not available.

Well, 3 months ago I replaced the filters (napa spin ons) and 22 qt of Rotella straight 40. I’m just assuming only 3 months and very very few miles would still be a thick oil. I don’t think it’s radiator as it’s not milky oil and radiator is beautiful toxic green. Again I can’t say the level is rising either.
maybe starters is have the oil tested and then I’ll know without guesswork.

 

[NY Tom]

30W straight is the original spec. A lot of guys are running 15W-40 now. Sounds like you are in a warm area 40W straight probably OK in my opinion.

In any case thicker oil won't get thinner all by itself. Something isn't right there. Testing should answer the question.

After that you are on to the checking and changing. At least you know the right direction.

 

[Mullaney]

Well, 3 months ago I replaced the filters (napa spin ons) and 22 qt of Rotella straight 40. I’m just assuming only 3 months and very very few miles would still be a thick oil. I don’t think it’s radiator as it’s not milky oil and radiator is beautiful toxic green. Again I can’t say the level is rising either.
maybe starters is have the oil tested and then I’ll know without guesswork.

.
As you said, it is relatively cheap to test the oil,

Those testing folks can tell you what is going on without guessing.
Unless you plan to do a cross country trip tomorrow, let the truck
sit there for a few days and get answers.

.

 

[V8srfun]

So you don’t have milky oil and are not losing coolant so that can be eliminated

you are not gaining or making oil and can not smell fuel in the oil.

the safest thing would be send a oil sample to black stone labs and see what they find.

is it possible that there is nothing wrong with your oil. I mean it always seems thicker when you are pouring it than when it drips off the end of your dipstick. I think it is a psychological thing that dirty oil just makes us think it is bad when it may not be.

 

[frank8003]

One hour of running a multi fuel and the new lube oil you just put in will look
like the oil you drained out but 80% of the nasties in it will be gone.
The nasties are the abusive diesel soot particles in the micron range that eat the parts.