My car has an engine that was all new about 600 miles ago. I had a couple of leaks from the rocker studs and fixed those. The engine seems pretty oil tight but I’m getting some seeping around the oil pump where it seals to the block. After driving a couple of times there are a few drips that splatter on my exhaust and bake in but I’m damned if I can find anything other than around the pump. Should I give up and just assume it is like an old Harley that is going to leak no matter what I do and just drive it?  I don’t know if it is possible to stop all the leaks.

2013 VS azure blue 2110cc

Original Post

Just broken in so high internal case pressures?  Does it have a crankcase oil breather system?  If not try driving with the oil filter cap loose/off.  Put your hand over it and feel for pressure.  (There is always some pressure - on worn engines or new not-broken in one there may be a lot of blow by the rings as they aren't sealed yet). OIl used is 30 weight or so?  Just random ideas.

There is supposed to be a slight interference fit between the engine case and oil pump (somewhere around .002 or .003" iIrc- someone please correct me if I'm wrong). The problem these days (and it has been an issue for for I don't know how many years now) is that a lot of pumps are machined slightly undersized, so when the engine warms up the press fit is lost, and now the pump is sucking air as well as oil. Gene Berg Ent. has been o-ringing pump bodies for over 20 years because of this. Some people coat both sides of the pump/case gasket with gasket goop to stop the leakage (with varying degrees of success) but the bearings are still fed aerated oil when the engine is warmed up.

The pump face and/or the cover may not be perfectly flat, which even with the correct gasket (the thinner one is the cover gasket- using the thicker one here will give poor oil pressure at operating temps) could be leaking as well. I think part of the problem is the gaskets themselves these days- they are supposed to be impervious to oil, but like the oil strainer/cover gaskets, a lot of them are cheap uncoated paper and seep oil. The easy solution (without taking the pump out to re-seal it)- wipe the bottom of the pump/case area with a rag before and after going out, and every time you stop when out all day?

Sorry I'm not much more help. Al

PS- If your car is dripping from the oil drain plate after an oil change and you've just put new gaskets in, the oil could be seeping right through the cheap pressed paper gaskets. Tightening the oil strainer nuts is not the answer, as it doesn't take much to dimple the 6mm studs in the drain plate (the torque on those 10 mm nuts is what, 6 or 8 lbs?). As I said above, I've heard of guys putting all kinds of gasket goop on the paper gaskets (one guy on the Samba sprays them on both sides with hairspray before installation; I would hazard a guess that the thinner the sealer is the better.

I agree that the paper gaskets are pretty thin, but the original VW gaskets were equally thin, too.  My current pump is a Berg and it doesn’t leak, but I would try re-gasketing the cover on yours as a first step.  Once the rear tin and pulley is out of the way the pump is easy to access.  See if the guys have a German or Brazilian gasket, too.  If you decide to swap the pump, I have a pump puller tool you can borrow.  Goop up the gasket with Permatex blue or black and put it together - that should do it.  

Come to think of it. If you’re going to the trouble of doing the cover gasket, you might as well pull the pump and do both body and cover gaskets to be sure.   Let me know if you want to borrow my pump puller.   

And are you sure it’s the pump leaking?  These engines are notorious for leaking behind the crankshaft pulley where there is no seal and when the oil runs down behind the pulley it looks a lot like the oil pump is leaking.  Mine does that all the time.  

I hate leaks so I’m probably too anal about it. That being said, the oil pump and cover are from CB and I’m pretty sure they are o ringed. The base plate I took off after the first oil change because the cover had no drain plug. I installed a new billet CB plate which is o ringed also.  I think most of the seepage is from the pump cover so I will check it this spring. The breather and cap are very dry internally and when I took the cap off and revved it a couple of time there was no pressure coming by my hand. I’m pretty sure the rings are seated pretty  well and it uses no oil.  Right now there is 5” of snow outside so Fugazy is hibernating.  Thanks guys for the tips.

Do you have a sand seal or no? There will always be a little weeping from oil mist through the crank slinger, even if you have the best breather system in the world, on a modified engine. Stock engines are pretty good and oil free, but modified engines move way more air due to under the piston swept volume. So since they move more air, the oil gets foamed up more.

RE the oil weeping from the oil pump: if you dry sump your engine you don't have to worry about sucking air or oil leaking out. Dry sump pumps are sealed from the engine. They draw through the pump for each stage. However, they are expensive. And complicated with MANY more locations for leakage. I no longer worry if my engine is starving for oil on the track or street though.

The back of the pulley is dry so it’s not leaking from there. The trouble is I think the fan is blowing the oil around and the only place it seems to leak is a little bit around the pump. It also could be one of the 2 fittings on the pump cover.  If I drive it about 10 miles or so, it might leak a drop or 2 on the floor.  That doesn’t bother me as much as it blowing on the exhaust and baking in. The header is ceramic coated so I use metal polish to clean it so it doesn’t build up. And this doesn’t include the trans which seeps also.  It just got new R & P and gears a hundred miles ago.

The back of the pulley itself will be dry.  The case, behind the pulley, might be wet from the bottom of the crankshaft down to the bottom of the oil pump so it'll LOOK like a pump leak when, in fact, it's coming from the crankshaft slinger.  

The fan directs its' airflow down onto the tops of the cylinders/heads and doesn't direct ANY air down over the oil pump.  Any air around the oil pump is just incidental air flowing around the bottom rear of the engine and has nothing to do with the fan.

I still think you have an oil slinger/crankshaft leak which is exasperated by engine blow-by pressurizing the case and blowing oil out past the crankshaft - just like a lot of us have.  Reduce the crankcase pressure with a better breather box and the oil seepage will diminish, too.

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