Weird Oil Leak

[Justin Loden]

For the last week I've been working on this car trying to fix the oil leaks. 90 mtx. It's leaking directly onto the exhaust. I replaced the timing belt, water pump, cam seals, front main etc... Still leaks. I'm in the process of replacing the oil pan gasket but it looks like oil is dripping off of the bottom bolt of the idler pulley mounting bracket. This bolt threads into the front of the engine right above where the oil pan bolts to. It looks like There is a seam between the block and whatever this part of the engine is. Or is it possible that when the oil pan gasket deteriorated that oil wicked up between the block and whatever this is. Just mainly wondering if anyone has had this same oil leak and what they did about it.
Thanks

 

[luigisho]

I'm having a hard time picturing the bolt. The oil pan seal is 2 curved rubber gaskets on the ends with rtv sealing along the sides. The oil filter area can leak. I need to look at the undercarriage to picture the problem. Also valve covers can leak down the block.

 

[Justin Loden]

I believe the housing that the oil filter screws onto is leaking so I'll have to look into that but that's on the front of the engine. This is actually on the passenger side of the engine where the belts are. It is the bottom bolt that holds the front idler pulley bracket to the engine. It screws in right at the bottom of the block right above the oil pan just to the side of the timing cover.

 

[Justin Loden]

You can see the bolt in this picture. It's the bolt on the right hand side of the picture right next to the lower coolant hose.

 

[rubydist]

It could be that the oil filter adapter seal is leaking. It also could be that the front cam seal is leaking, even though you just replaced it as sometimes the old seal has worn a groove into the cam.

 

[Greg Millard]

Oil leaks require dilgence & patience. The only way I have been sussessful to track em down is to first take an inordinate amount of time drying off EVERYTHING ...leave it for 30 min & if still dry start the engine (on a lift may make it easier) while closely watching the area and look for the very first hint of moisture - repeat until you arrive at the source.

 

[luigisho]

The front is usually considered the accessory side of the engine. If locating the leak is a real issue there are dyes you can add to help track it.

 

[BaySHO Performance]

You can see the bolt in this picture. It's the bolt on the right hand side of the picture right next to the lower coolant hose.

That bolt doubles as a bolt for the oil pump. I've seen leaks there before. Most likely is that the oil pump gasket has failed. That's the oil pump that the crankshaft goes through.

You will need to remove the oil pan to remove the pump. Gasket kit is Felpro TCS 45871, available from Autozone.

Oil cooler leak behind the filter:
https://shosource.com/products?olsPage=products/oil-cooler-o-ring-gasket-89-99

Oil leaking on to the exhaust: won't be the rear valve cover seal if it's only just started to happen. Did you replace the cam seal behind the cam sensor on the rearmost cam? Run you finger along the bottom of the sensor to see if it's oily. Only other potential culprit is the power steering pressure hose. Low possibility of the PS pump leaking.

 

[Justin Loden]

Thanks for the replies everyone. Waiting on the oil pump gaskets from autozone so I can replace them. It kind of worked out ok since I already had the oil pan off in order to reseal it. It was leaking really bad as well. All I have to do is take the timing belt stuff back off to get to the oil pump then should be good to go. Thanks again.

 

[luigisho]

You have stuff out of the way underneath? Most of it is rtv and you want a straight shot when lining it up.

 

[Justin Loden]

Yep, got the starter and the y pipe out of the way. It's still a bit of a tight fit. Have to tilt it a certain way to get it to go but shouldn't be a problem. Also replaced the seal on the oil cooler while I had the starter out of the way. Been dry fitting it to make sure I can do it without an issue for when I actually get ready to put it on.

 

[luigisho]

Excellent idea to replace the oil cooler seal while you have room and time. Hopefully this will clear up your leaks. It's an old SHO... there will always be something.