Gassy smell in crankcase

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vicQ45
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Car: 1979 Cadillac Eldog, 1987 Wagovan, 1968 Firebird 400

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I opened up my crankcase after an oil change and noticed a strong gasoline smell(smells like mower gas ) i assume its leaky rings, but how bad is this.. can it be fixed or slowed down with any method, how expensive to fix? any input would be nice


DAEDALUS
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I would sooner suspect a leaking injector. It would have to be a lot of very rich blow-by to collect in the oil like that and not evaporate. Do a rail leak-down test.

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vicQ45
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sounds like a plan. about how much does a rail leak-down test usually run?

DAEDALUS
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Probably costs less to buy the tool and do it yourself. Takes 15-30 minutes, tool costs maybe $30. Most shops have min labor charges. Maybe you can find a place to rent the tool. Tee into the fuel hose past the fuel filter. Pressurize the rail (turn key to ON). Clamp off both in and out hoses to isolate rail. Then just wait and watch the pressure gauge.

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vicQ45
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that sounds easier than i thought! where could i get this tool?.. i got $30 to spare its not a big problem. assuming it is an injector, how would i find out exactly which one it is? Man daedalus you are helpful to people who are new to this like myself. thanks!

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vicQ45
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I also wonder if this might be why my fuel seems to disappear fastest at startup and the gas smells richer than our other two cars.. is it possible it is just an o-ring or would the injector surely need to be replaced? i'm just hoping i don't need to pull the plenum :-P

EDIT: ok it's 3:52AM here. i'm kind of out of it... do i just need a fuel pressure gauge?
Modified by vicQ45 at 1:53 AM 3/3/2005

DAEDALUS
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Joined: Mon Jul 22, 2002 8:50 pm
Car: 1990 Infiniti Q45

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Yes, fuel pressure gauge is all you need, and a brass 5/16" barbed T-fitting, plus maybe some extra 5/16" fuel injection hose. Make sure the gauge is for fuel injection. Most go to 100psi. I got some fuel hose pinch-off clamps from Harbor Freight for like $2 each, or you can use a couple vise-grips and towels to protect the lines.

I would think it's the seal and not the injector itself, unless the tip is cracked. To find out which injector it is I'm afraid you would have to pull the spark plugs. Only way I know how.

DAEDALUS
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These guys get way to much of my paycheck:

http://thetoolwarehouse.net/shop/TTW305.html

I have had a problem with customer service once, which I took up with my credit card company, but their prices are ROCK bottom. Scroll down--they have the gauge you need for $27.18, even comes with the fitting. If you spend $100 you get free shipping, and no tax collected if you're out of state. Surf around, you can easily spend $100...or $1000. LOL

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vicQ45
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Joined: Wed Nov 17, 2004 4:43 pm
Car: 1979 Cadillac Eldog, 1987 Wagovan, 1968 Firebird 400

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so when i pull the plugs what do i do? do i just look for whichever one(s) is/are wet?

DAEDALUS
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Car: 1990 Infiniti Q45

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Could be wet or hopefully there'll be one plug that is clearly different from the other 7, with a lot of black soot on it. Also, with the plugs out maybe you can tell by smell, with a flashlight, or with a narrow dowel or long q-tip.


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