Chris2012 Posted October 22, 2012 Report Share Posted October 22, 2012 I'm going to attempt to attach photos (yay it worked, but they're not in order). I'd say it loses about a quart a week. 182,000 miles, plan on taking it on a long trip (~1300 miles). She's all I got right now I'll try to explain. There's a recesses area just to the right (perspective of someone standing in front of the hood/engine) of the plenum?/throttle body?, oi the thing that says "3.1 Multiport FI". Basically just behind (same perspective) the filler cap. It's oily down in there. It leaks out apparently, then travels toward the rear of the car. You can see the pathway in one of the pictures. Sometimes it even seems like coolant comes out of there also. No oil is not smokey or anything like that, looks normal. Assuming it is a crack, I'm planning on getting in there, cleaning it thoroughly, then jamming epoxy putty in there. I should think it would hold for a while. Oh it's a one way trip Quote Link to comment Share on other sites More sharing options...
80's tech Posted October 23, 2012 Report Share Posted October 23, 2012 o-ring on oil pump drive shaft? [ where distributor would be ]. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted October 23, 2012 Report Share Posted October 23, 2012 that's exactly what it looks like from those pics. Quote Link to comment Share on other sites More sharing options...
19Cutlass94 Posted October 23, 2012 Report Share Posted October 23, 2012 Yep thats what it is. Those o-rings get hard and brittle and crack over the yrs letting oil out. Quote Link to comment Share on other sites More sharing options...
Chris2012 Posted October 23, 2012 Author Report Share Posted October 23, 2012 Yep thats what it is. Those o-rings get hard and brittle and crack over the yrs letting oil out. I'm going to want to kiss all 3 of yous if it's that simple. But how would that explain the occasional coolant leak? Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted October 23, 2012 Report Share Posted October 23, 2012 i've had intermittent "phantom" coolant loss with 3.1s and 3100s for years.... every couple of months, i throw in a quart or so of water or coolant, depending on the season and it's beyond full. unless it's getting into your oil or you're burning it, i wouldn't worry about it too much. Quote Link to comment Share on other sites More sharing options...
19Cutlass94 Posted October 23, 2012 Report Share Posted October 23, 2012 Coolant leak is a seperate issue. That leak there is strictly oil. Check everything, coolant wise, and get rid of those stock GM clamps on the hoses. They are garbage. Quote Link to comment Share on other sites More sharing options...
Chris2012 Posted October 23, 2012 Author Report Share Posted October 23, 2012 i've had intermittent "phantom" coolant loss with 3.1s and 3100s for years.... every couple of months, i throw in a quart or so of water or coolant, depending on the season and it's beyond full. unless it's getting into your oil or you're burning it, i wouldn't worry about it too much. Nah, I have to put in a quart a day (a little less usually since the hottish weather broke). I'm going to just heat muh baby up good one of these days and watch where all the spew is coming from. I could swear though that I saw something real runny coming down the same pathway as the oil. I gotta scope this all out. One of these days. Thanks for all the help. Assuming it is that o ring, and I assume any o ring of the proper size is suitable (?), how big is the job? Quote Link to comment Share on other sites More sharing options...
19Cutlass94 Posted October 23, 2012 Report Share Posted October 23, 2012 Just get it from the GM dealer. They have them in stock and its only like a $1. To do the job, remove the UIM, then youll have free access to it. Quote Link to comment Share on other sites More sharing options...
rich_e777 Posted October 23, 2012 Report Share Posted October 23, 2012 (edited) Is this the same for a 3100 over a 3.1 and could this be mistaken for a leaky end seal on the LIM? Is the point in question just aft and below the throttle body? Ive been suspecting on mine as oil runs down the front and rear of the engine it was that lim gasket rtv seal. Edited October 23, 2012 by rich_e777 Quote Link to comment Share on other sites More sharing options...
19Cutlass94 Posted October 23, 2012 Report Share Posted October 23, 2012 The oil pump drive seal is the same on the 3.1 and the 3100. LIM gaskets 9 times out of 10 will fail internally. Quote Link to comment Share on other sites More sharing options...
Chris2012 Posted October 23, 2012 Author Report Share Posted October 23, 2012 (edited) uh, what's a UIM and an LIM? I'm thinking upper intake manifold and lower intake manifold, but since I'm not a mechanic that might be gibberish. Edited October 23, 2012 by Chris2012 Quote Link to comment Share on other sites More sharing options...
19Cutlass94 Posted October 23, 2012 Report Share Posted October 23, 2012 You are correct. Quote Link to comment Share on other sites More sharing options...
rich_e777 Posted October 23, 2012 Report Share Posted October 23, 2012 The oil pump drive seal is the same on the 3.1 and the 3100. LIM gaskets 9 times out of 10 will fail internally. internal failure results in a vacuum leak and a obvious sound instead of oil leaking right? i got to keep a list of all this stuff like we do for different powerplants on aircraft, makes the diagnosis alot quicker. Quote Link to comment Share on other sites More sharing options...
19Cutlass94 Posted October 23, 2012 Report Share Posted October 23, 2012 No. When a LIm gasket fails, it fails by the dead coolant ports. It rips the gasket, allow the coolant to mix with the oil internally. Very rarely will a LIM leak oil or coolant externally. No vacuum will be affected, but the cooling system pressure will be less since there is a leak. It is not a vacuum leak does not make sound or anything else. Quote Link to comment Share on other sites More sharing options...
LumiLTZ Posted October 24, 2012 Report Share Posted October 24, 2012 Agree on the oil pump drive seal being your oil leak. If there's coolant down in that area too, it could be the heater hose connection that goes into the LIM under the TB. It's a quick-connect fitting that looks like the following: Quote Link to comment Share on other sites More sharing options...
Schurkey Posted October 25, 2012 Report Share Posted October 25, 2012 The oil pump drive o-ring is "special" in that it's a much higher-quality material than generic parts-store o-rings. The original o-rings failed because they were a low-budget material--GM upgraded the O-ring later, and that's what's sold by GM now. I have every expectation (but have not verified) that the 3.1/3100 distributor drive is the same as the 3.4 DOHC engine uses: We 3.4 owners install the paper gasket for "insurance" since the rear head has to come OFF of the 3.4 to remove the oil pump drive. I'm thinking the pushrod engines don't require head removal to pop the oil pump drive out for o-ring replacement. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted October 25, 2012 Report Share Posted October 25, 2012 correct, no head removal required for the OHV 60V6, and it is the same drive setup. Quote Link to comment Share on other sites More sharing options...
rich_e777 Posted October 25, 2012 Report Share Posted October 25, 2012 (edited) i guess i meant to say the end seals that are RTV, i was told if those fail they could leak oil which is a common problem on GM V6s. misinformed i was? Edited October 25, 2012 by rich_e777 Quote Link to comment Share on other sites More sharing options...
19Cutlass94 Posted October 25, 2012 Report Share Posted October 25, 2012 As long as one puts down a good bead of RTV, uses the correct type of RTV, and cleans everythig before putting the RTV on, the LIM will almost always fail before the RTV. When people take short cuts on a job they spread the word then that becomes a 'common issue' As long as a job is done correctly, its usually never an issue more than once. Quote Link to comment Share on other sites More sharing options...
emptytank Posted November 14, 2012 Report Share Posted November 14, 2012 I would put my money on the intake gasket, specifically the silicone at the end. It could be oil pump drive oring, and it is alot easier of a fix to try that first. After you pull plenum off ( gotta be done for both jobs) you should get a better view of where oil is comin from. Quote Link to comment Share on other sites More sharing options...
EviLette Posted November 15, 2012 Report Share Posted November 15, 2012 uh, what's a UIM and an LIM? I'm thinking upper intake manifold and lower intake manifold, but since I'm not a mechanic that might be gibberish. UIM - Upper Intake Manifold (the big aluminum piece on top that has 3.1 MPFI stamped into it LIM - Lower Intake Manifold (I *think* this is what's below the Upper, and what the injectors/fuel rail plug in to but not 100%) Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted November 15, 2012 Report Share Posted November 15, 2012 UIM - Upper Intake Manifold (the big aluminum piece on top that has 3.1 MPFI stamped into it LIM - Lower Intake Manifold (I *think* this is what's below the Upper, and what the injectors/fuel rail plug in to but not 100%) This is correct. Quote Link to comment Share on other sites More sharing options...
Crazy K Posted November 15, 2012 Report Share Posted November 15, 2012 MISINFORMATION ALERT: the 3.1 MPFI uses a paper one piece intake gasket and does not rely so silicone RTV pretty much at all!!!!!!!! * it calls for it only at the point where the intake gasket touches the valve cover gasket * the 3100/3400 SFI uses two nylon and silicone gasket (factory or cheap style intake) with RTV along the flat center at both ends over the cam. this gasket is known for having coolant leaks, not oil leaks. All 60 degree engine use the same oil drive design and the same dummy distributor head. They all use the same parts and seal. they all LEAK. I did a write-up on how to fix: http://www.w-body.com/showthread.php/8442-O-Ring-(Oil-Pump-Drive-Seal)-Fix-(Pictures)?p=813142&viewfull=1#post813142 but you can read the whole thread for more info. and the coolant fitting is: DORMAN Part # 800401 Quote Link to comment Share on other sites More sharing options...
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