mystery leak

in10s · 01-20-2006, 10:10 AM

It's a-leakin... Oil from the front all the way back. If the oil cooler seals are leaking wouldn't there be oil on the oil cooler? If it's not the oil cooler what else would be likely?

in10s · 01-20-2006, 01:11 PM

I rechecked the pushrod tube seals that I just replaced and it would appear that at least one is still leaking. I'm not looking forward to doing this again, but whatever it takes..... What could have gone wrong?? Could the tube itself be at fault?

Headrage · 01-20-2006, 03:24 PM

If the oil coller seals are leaking it won't necessarily mean that the oil cooler will be oily. The seals are at the back of the cooler. How bad is it leaking?

Could be a galley plug.

in10s · 01-20-2006, 03:57 PM

Its leaking a steady drip when it warms up. I've got it on jacks now so the front of the engine is lower than the rear. The obvious drip is coming from between the two intake pushrod tubes on the passenger side. I just replaced all of the pushrod seals a few days ago. I used the Viton seals and it wasn't easy getting the tubes to reseat. If the leak is from the inner tube seals I gotta admit that I'm a little pissed and frustrated. The oil pools between the two tubes and drips very annoyingly down.
I'll check my Haynes manual to see what the galley plug is.

Conrad W Peden · Conrad W Peden's Garage

Hows your oil pressure sender?

Dave at Pelican Parts · Dave at Pelican Parts's Garage

I'm not sure Haynes will have any info on oil gallery plugs. Those are the pressed-in aluminum plugs that cover the holes in the crankcase where they drilled to make the oil galleries. Those are the internal oil passages inside the crankcase. Look for smallish round flat spots on the front of the motor (if your fan and fan shroud are off).

When an engine is out, it's a good idea to epoxy over them to help keep them from starting to leak. When an engine is rebuilt, it's a good idea to remove them so you can really clean the oil galleries out and then to tap the holes and screw in pipe plugs.

--DD

in10s · 01-20-2006, 05:43 PM

After learning about the gallery plug leak possibility, now pulling the push rod tubes again doesn't sound so bad!!! In fact, I hope they are leaking!!!!

in10s · 01-24-2006, 03:08 PM

It's not the push rod tubes. There is a space between the center of the tubes where the oil gathers. Any ideas other than the galleries?

Dave at Pelican Parts · Dave at Pelican Parts's Garage

The inner ends of the tubes can leak down onto that area, sometimes. There is a case through-bolt there on the one side (I think it's the right side only). The bolt has a seal on it but that sometimes can leak. This is the bolt that the oil pickup hangs from; hopefully you haven't overtightened the sump plate retaining nut. On the left side (I think) of the case may be (not present on all motors) a threaded plug which is the cover for the oil pressure control valve. It might leak.

Hmm, what else would get to that area? Not sure off the top of my head.

--DD

bryanf · 01-24-2006, 06:14 PM

Sounds exactly like how my car was when the oil pressure sender went bad. It's only a few bucks as I recall. It might be worth a shot to simply replace it and see if that helps.

in10s · 01-29-2006, 02:36 PM

It looks like I have located the mystery leak. It is coming from the case bolt that is above and between the pushrod tubes on the right side. If no one has a better idea I am going to clean the area around the bolt and epoxy it. The real difficulty here is, I can't see anything.

Dave at Pelican Parts · Dave at Pelican Parts's Garage

I had a similar leak there; I replaced the sealing washer on the bolt and it seemed to fix the leak.

--DD

henrymiller · 11:21 AM

Have a similar leak without having a solution yet. The oil is dropping from the oil filter with 1 - 2 drops per second. What is really curious is the fact that this only appears once the engine is cold. After warming up the leak stops.
In my manual I have found the remark that the oil pressure valve may be stuck at its upper position and that once the oil is cold it is therefore forced to flow through the oil cooler. As the oil is to thick for the cooler it then leaks out. The lower valve I did check and it seems to be OK. In my manual is also shown a second valve below the first cylinder. However, my engine does apparently not have this second valve...
Any idea what the reason for this leak could be??

in10s · 01-30-2006, 02:58 PM

I hope that you are talking to Dave, Henry; because I am not the person to ask. I would, however like to know the answer for future reference. Yikes.... I hope I'm not jinxing myself to a life of chasing down sneaky oil leaks.

Joe Ricard · Joe Ricard's Garage

All type IV cases have a oil pressure control valve between the cylinders on the drivers side. Looks like a plug with 8 point socket head. A 3/8 extension works great for this one.

There is a product I get at the FLAPS to put under the washers of through case bolts. Loctite anerobic gasket sealer. Comes in a blue tube, the product is red Jelly like and stays flexible and makes a real thin film seal.

Dave at Pelican Parts · Dave at Pelican Parts's Garage

Quote:

Originally posted by Joe Ricard
All type IV cases have a oil pressure control valve between the cylinders on the drivers side.

No, that's not true. A number of 914s do not have them, and none of the hydro-lifter Bus engines do either. Probably some of the solid-lifter ones are also missing this.

I already communicated with Henry about his leak, and pretty much suggested all of the stuff that is mentioned here in this thread so far.

You can clean up the engine as best you can (that engine cleaner stuff works pretty well, Simple Green or Oil Eater do also; scrape off the heavy accumulation of crud first!) and run the car for a little while, then check for fresh oil. Usually the leak is very close to the highest and furthest-forward point where you have fresh oil.

--DD