Oil Level climbing

Motohead

SCCoA Member
I have a fresh professionally rebuilt engine with new pistons bored block all tollarences were checked during assembly It has about 1000 miles on it I checked the oil level and noticed it was overfilled (almost 2 quarts) the oil looked thin on the dipstick I changed the oil and it seemed thin and smelled of gas I have put about 50 miles on the car and the level appears to be rising again. Maybee 1/4 quart over. My injectors were tested and flowmatched at installation. I have run a leak down test at the fule rail and it holds pressure. The car isnt smoking and running well any ideas what could be causing this?
 
Sounds like your fuel pressure regulator diaphragm may be blown. Check your fuel pressure. If it is too high (60-90psi), then that is your issue.....This will cause diveability issues though.
 
Could be your lower intake gasket is leaking. Happened to me when I did mine and it'll cause the same problems of gas fouled oil.
 
Definately a fuel issue, with a leak that bad you should get it fixed quickly before it washes down the cylinders.
 
Could be your lower intake gasket is leaking. Happened to me when I did mine and it'll cause the same problems of gas fouled oil.

tell me more because I have had poor vacume for ever even before this rebuild and havent found the leak. I went ahead and had the machienist do the pans and lower intake this time around he specializes in HP moters from circle track all the way to top fule He has done my bigblock marine moter and it runs great But I guss anyone could make a mistake
 
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I don't have much to add specifically to the problem, but I would definitely talk to the engine builder.
 
Are you sure it isn't coolant? I replaced my timing chain cover gasket and didn't use a sealant (it was the fancy blue type how was I to know :rolleyes:) and I got coolant into the crank case :eek: . Had to tear down and reassemble with RTV. If you drain some of the oil out, if there's coolant in it, you'll know.
 
after pulling off the intake could you see where it was leaking ?

Yup. Mine was mostly due to a little of the high tack gasket sealer that got into the coolant passage and allowed coolant to seep into the #6 port. Worth looking into.
 
I'm leaning towards it being fuel, but I agree it should exhibit other issues if that were the case...

If you run out of obvious things to check, I believe some of the parts house sell an inexpensive oil testing kit that might help nail it down - good luck in any case.
 
pull the vacuum line off top of regulator if there is fuel coming out there then you found your fuel leak at the regulator.

did you drian oil lately? Stupid question but coolant will be at bottom and fuel will mix with the oil.

place the fuel presssure guage on schrader valve and let motor run till pressure stabalizes, then shut motor off and come back in like 15 min. if you have no pressure on the guage at that time (yes it will have dropped some, that is normal) but if all pressure is gone you are leaking some where. probably injectors or regulator, you can then repeat this check pinching off the return line if pressure holds then you have a bad regulator or injectors. if it doesnt then the pump check valve (same thing mind does) is bad.
 
pull the vacuum line off top of regulator if there is fuel coming out there then you found your fuel leak at the regulator.

did you drian oil lately? Stupid question but coolant will be at bottom and fuel will mix with the oil.

place the fuel presssure guage on schrader valve and let motor run till pressure stabalizes, then shut motor off and come back in like 15 min. if you have no pressure on the guage at that time (yes it will have dropped some, that is normal) but if all pressure is gone you are leaking some where. probably injectors or regulator, you can then repeat this check pinching off the return line if pressure holds then you have a bad regulator or injectors. if it doesnt then the pump check valve (same thing mind does) is bad.

Oil had no coolent in it was very thin and smelled of gas
Ill check the FPR vacume line for fuel
I re-tested pressure (I have a FP gague mounted on the schrader valve) The first test I only watched it for about 5 min this time I waited 15 min 38Lbs at the begining it droped to 15 LBS after 15 min This is all i have time for this morning (Gotta go to work) I'll check the vacume ine this afternoon.

This couldent have anything to do with the crosstalk vacume line could it ? Mine is removed as i have a MP plenum
 
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Hows the driveability side of it? Does it seem like it is running normal? The reason I ask is the only thing that I can think is that maybe the EEC is hanging an injector open with the engine running.
 
FP shows 38 with KOEO
That is good. Check it KOER as well. Regulators are vacuum regulated. Blown vacuum diagphram will show after it is started. No vacuum with the enigne off....obviously. Still normal with it running then you are good on that end...
 
Oil had no coolent in it was very thin and smelled of gas
Ill check the FPR vacume line for fuel
I re-tested pressure (I have a FP gague mounted on the schrader valve) The first test I only watched it for about 5 min this time I waited 15 min 38Lbs at the begining it droped to 15 LBS after 15 min This is all i have time for this morning (Gotta go to work) I'll check the vacume ine this afternoon.

This couldent have anything to do with the crosstalk vacume line could it ? Mine is removed as i have a MP plenum

Bob,

Fuel pressure sounds normal. Eliminating the cross talk hose wouldn't matter. From what your describing it sounds like your running it too rich and washing down the cylinder walls with fuel. What A/F ratio are you running at idle and part throttle ?

I was having a problem with my 91 loading up on fuel if the car sat idling at a stoplight or in traffic for more than a couple minutes, and Dave Dalke had to do something special to the tune to correct the problem. I think it had something to do with o2 sensors not staying hot enough (long tube headers) and that affected short term fuel trims and adaptive, but I could be wrong.

David
 
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