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Mayne
Hi everyone, I picked up a 75 914 last summer and have finally gotten it running well enough to drive (which I want to do!). The problem is, a substantial oil leak that I thought I'd fixed is still there. Previously, it would spray oil from the lower drivers side at revs above idle. Not finding a clear source, I dropped the motor and resealed the oil pump, which really seemed like the issue. Motor back in now and the leak is the same. It seems to rev or crankcase pressure related, but now I'm thinking pushrod tubes or valve cover gasket. Any thoughts would be much appreciated.

I'll give a proper introduction with some photos soon. Cheers!
ConeDodger
If you dropped the motor, you should have completely resealed it. Do it again, but this time replace all the pushrods tube seals and front and rear seals. Adjust the valves while its out on the stand as well. Check your galley plugs.
Dave_Darling
Do you have a thermostat? The pulley wheel for the thermostat wire mounts on a bolt in a hole that goes into the sump. If the bolt is left out, you have a nice leak there, but only intermittently!

--DD
TheCabinetmaker
thisthreadisworthlesswithoutpics.gif
rgalla9146

Spraying out ?
Is your crankcase ventilation completely plugged ?
If not, you're back to the oil pump, the oil filter, oil filter console, oil pressure switch
or galley plugs behind flywheel.
Mayne
QUOTE(ConeDodger @ Mar 12 2017, 10:06 PM) *

If you dropped the motor, you should have completely resealed it. Do it again, but this time replace all the pushrods tube seals and front and rear seals. Adjust the valves while its out on the stand as well. Check your galley plugs.


agree.gif Yes, I failed on the due diligence. Will take another more thorough shot at it.
Mayne
Thanks for the suggestions. The motor will come back out and I will check and fix everything I can. I plan to start a project thread, but here are a few photos:
In the shop:
IPB Image
Engine back in with rebuilt Webers:
IPB Image
First drive with my brother's 69 911:
IPB Image
Looking good with my 951 and 986:
IPB Image

beerchug.gif
r_towle
QUOTE(Dave_Darling @ Mar 12 2017, 11:47 PM) *

Do you have a thermostat? The pulley wheel for the thermostat wire mounts on a bolt in a hole that goes into the sump. If the bolt is left out, you have a nice leak there, but only intermittently!

--DD

this
Dave_Darling
Seriously--take a look at the driver's side of the engine from underneath the car. There should be a pulley wheel up toward the front of the engine.

Here's a photo of what it would look like if everything were perfectly spotless (which it never is!) --
IPB Image

If you don't have that pulley wheel, look for the hole where it should be. Put a bolt in that hole and see if your leak goes away.

--DD
porschetub
Nice original looking car beer.gif ,I'am presuming you have a hose going from the breather to the carb and that your oil pressure switch has a wire for it.
Before you pull the engine again clean it down with brakeclean (or similar) then run it again without driving it after placing a piece of white cardboard below the engine.
I was chasing leaks under my "6'' and found this a good method,have done the same with my T4 and other less notable cars biggrin.gif .
Pushrod tube seals are the most likely culprits along with the rocker cover gaskets,I used hydraulic grade''o'' rings on the tubes and a good non-hardening sealer,i have always sealed my gaskets to the rocker covers as well( but not to the head of course ),as mentioned there are plenty of other places that can leak.
Oh and by the way welcome.png

Mayne
QUOTE(Dave_Darling @ Mar 13 2017, 11:34 AM) *

Seriously--take a look at the driver's side of the engine from underneath the car. There should be a pulley wheel up toward the front of the engine.

Here's a photo of what it would look like if everything were perfectly spotless (which it never is!) --
IPB Image

If you don't have that pulley wheel, look for the hole where it should be. Put a bolt in that hole and see if your leak goes away.

--DD



Thanks, I'll take a look next time I work on it. The leak seems to be higher up, like even above the push rod tubes, and I think the fan is spraying the oil around. I appreciate all the knowledge and suggestions! Maybe I can find the culprit without dropping the motor.
Shadowfax
What about the oil cooler seals?
brant
as far as spraying goes
I've also had the oil pressure sender loose where it actually sprayed oil. In my case it was easy to find because it was spraying up through the engine grill and onto the rear glass

but most seals tend to leak and not spray
(example: I just replaced my distributor seal which was causing a downward drip of oil)
sdoolin
That is great information about the Tstat roller going all the way through the case. I did not realize this and have been stumped as to why my Tstat roller always has a small drop of Brad Penn 20W50 on it. I'll pull that bolt and add some thread sealer.

Love this site...
SirAndy
QUOTE(r_towle @ Mar 13 2017, 10:17 AM) *
QUOTE(Dave_Darling @ Mar 12 2017, 11:47 PM) *
Do you have a thermostat? The pulley wheel for the thermostat wire mounts on a bolt in a hole that goes into the sump. If the bolt is left out, you have a nice leak there, but only intermittently!

this

agree.gif
bandjoey
QUOTE(Mayne @ Mar 13 2017, 11:19 AM) *

Thanks for the suggestions. The motor will come back out and I will check and fix everything I can. I plan to start a project thread, but here are a few photos:
In the shop:
IPB Image
Engine back in with rebuilt Webers:
IPB Image
First drive with my brother's 69 911:
IPB Image
Looking good with my 951 and 986:
IPB Image

beerchug.gif


The answer clue is the oil breather plumbing on top of the carb air cleaner. Oil vaper hoses from both heads drain into the carbs or a breather box. If the hose is off one or both it'll blow oil everywhere. Ask people following me how I know. headbang.gif
rgalla9146

If your crankcase vents have strong pressure you have big problems.
If your rear bumper is oily that's a bad sign.
Mayne

[/quote]

The answer clue is the oil breather plumbing on top of the carb air cleaner. Oil vaper hoses from both heads drain into the carbs or a breather box. If the hose is off one or both it'll blow oil everywhere. Ask people following me how I know. headbang.gif
[/quote]

I'll check into that as well, though there is no oil leaking on the top of the engine.
Mayne
THANK YOU!! Oil leak fixed.
Missing thermostat pulley, no bolt:
IPB Image
New, super fancy bolt:
IPB Image

Drove it for half an hour and other than a few whiffs of oil burning off the heat exchangers, looks good. What fun cars! My 944 turbo and Boxster are amazing cars, but the 914 feels so light and interactive, and the torque makes it quite entertaining.

beerchug.gif
rgalla9146
Excellent !
Wish I could say I helped.......did learn something though !
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