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Posted by: ljubodraz Sep 24 2014, 04:56 AM

Hello All,
Bought my '75 1.8 dual carb 914 a few months ago and have been loving it. First time poster but long time reader here. She ran fine until the impeller hub spun free of the crank and began to overheat. Based on oil temp gauge, it didn't get into the red zone. Anyhow, I've dropped the engine to repair the impeller hub and am now faced with what else to repair while it's out. Bottom of engine and trans were wet from oil leaks. Not a highly uncommon problem I'm sure.

What has me most concerned is the leaks at the cylinder/case interface of all four cylinders. I was hoping the oil was being blown back from oil pressure sender but no luck as all four cylinders are same and sender connection is dry. Never got around to performing compression test but engine pulled strongly.


The second major issue of concern is that the Melling oil pump might be leaking. I can't tell for sure but would hate to repair after putting engine back.


My questions regarding cylinder leaks:
Should I/can I bother to re-torque the head bolts? I'm hoping that the leaks were exacerbated by the crank vent being partially blocked. How concerned should I be? I'm not ready for a rebuild.

My questions regarding oil pump:
What should I try to do? Replace gaskets? Replace pump altogether? I get intimidated by oil pump posts regarding getting the right clearances, difficulty in pulling pump out, etc.

Many thanks in advance for your help as I am getting stressed over this.

Posted by: lsintampa Sep 24 2014, 07:05 AM

if you're not ready for a rebuild, clean it up, adjust valves, put it back, drive it, let it leak .... all it will hurt is the ground where you park it

Posted by: stugray Sep 24 2014, 07:17 AM

And I am not convinced that oil buildup is really a leak around the cylinder bases.
What does the oil cooler look like?

Dont worry about it, clean it well. Might as well replace that front oil seal while its right there.

Posted by: RobW Sep 24 2014, 07:23 AM

Fuel lines, injectors, oil cooler seals, anything else that jumps out at you. I'm running a 2056 with 2500 miles that leaks (synthetic) oil. Be careful with the wiring!

Posted by: ljubodraz Sep 24 2014, 07:56 AM

Thank you very much for the responses so far. I'm grateful.

What about re-torque of head bolts?
What about oil pump?

It is possible that oil on cylinders came down from oil fill/breather with PO but the tins above cylinders have what appears to be oil blown up from cylinder base too.

Oil cooler was dry but will replace seals.
Already planning on replacing:
Both seals at impeller hub
Push rod tube seals.
Maybe oil filter flange gasket.

Posted by: lsintampa Sep 24 2014, 08:51 AM

Push rod seal replacement is fairly significant... you will need to remove the push rod assembly from the heads -

http://forums.pelicanparts.com/porsche-914-914-6-technical-forum/298994-how-replacing-pushrod-tube-seals.html

Posted by: stugray Sep 24 2014, 10:43 AM

Remember that this engine is pulling air in from the engine bay and blowing it downward across the cylinders.
So I suspect that the oil you see is crankcase venting "smoke" that is blown down through the cylinders and leaves that "sludge" on top of the cylinders.
Notice how it is concentrated on the "leading edge" of the restriction as the air is forced to turn the corner and go down through the colling fins?

I suspect that you have some on the oil cooler too.