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Oil leak???

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69tr

Jedi Trainee
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I took the car out for a short trip today. The weather was pretty warm and I got stuck in traffic. The temp ran pretty high and the carbs vapor locked. When I got pulled over and raised the hood I saw a lot of oil on the left side of the engine. I am talking about a significant amount of oil. I thought it might be coming from the dip stick but I removed it and revved the engine and that was not the problem. I could not see any place it was coming from.

I also thought about a valve cover gasket but there was no oil on the head.

I did notice that the oil pressure was not as high as it usually is. It usually runs about 75 psi at speed. Today it was about 55-60. I thought that might be because engine temp was up a little.

I had removed the distributor earlier and worked on the centrifugal advance.

I didn't have time to check it out tonight. I hope take a closer look tomorrow. If anyone has any ideas let me know.

BTW I am going to order heat shields for the carbs and start looking for an electric fan.

Thanks, Pete
 
Cracked plastic on the top of the oil pressure switch?
 
If you find that the oil is coming from the mating surfaces between the head and the block, it's because the crankcase pressure has built up and not being relieved properly thru the valve cover vent.
 
A useful diagnostic tool for sourcing leaks, oil, transfluid, etc. is spray on footpowder, like Desenex, etc.

I kept a bottle in my box when I was a full time wrench.

Clean the component where the leak is, spray the powder on, be liberal, go for a drive, come back and you can source the leak by following the trail through the sprayed on powder...
 
:iagree:

Best of all, you'll never have to worry about your engine getting athlete's foot!
 
Poolboy, that is where the oil appears to be coming from. I recently replaced the PCV valve. I have the air cleaner off and there seems to be vapor coming out of it. If I disconnect the hose coming out of the valve cover and it doesn't leak could the PCV valve be bad? It doesn't look that complicated. But then again, I'm a simple guy.

Thanks, Pete
 
Len Renkenberger (6-Pack founder) makes mention of this situation. As you probably know the 69's were the only year that the TR6 used a PCV valve, Beginning in 70 the valve cover vent relieved crankcase pressure by routing the valve cover hose to a low vacuum fitting on the carbs.
You could do as Richard Good has done and put a "T" in the brake servo hose and route the valve cover hose with a modern PCV valve to the "T".
I'm not sure I like that idea because you'd be using full manifold vacuum to relieve the pressure. That's about 17 or 18 in-Hg compared to about 2 in 70-76 engines "evacuation nipples" (at idle speeds).
You might try blanking the PVC hole, eliminating the "T" and the hose to the PCV, and use a straight 1 piece hose to the air box.
Or try a new PCV, but I think I'd try to follow Triumph's lead and eliminate the original style PCV in some fashion.
 
My money's on the oil switch leaking, also check the oil pressure gauge hose connection to the block; it's only a push on fit and mine came off one time with a lot of oil all over.
 
I am pretty sure it is not the oil pressure switch. I tapped it up with masking tape. There was no oil on the inside or outside of the tape.

Unless I am very wrong it is coming from where the head mounts to the block.

Have any other '69 owners had this problem and how did you fix it?

I think I am going to follow Poolboy's advice and look toward the PCV valve or some other way to scavenge the oil from the valve cover.

Thanks again to everyone, Pete
 
Pete, just be sure you have a pretty good vacuum on the down stream side of the PCV...however you route it. The air filter box is usually pretty good because it has access to the suction of the carbs, but the actual filters may clog up prematurely because of the oil vapors.
If that proves unsatisfactory, then you might just have to consider full manifold vacuum for relief.
 
69tr said:
Unless I am very wrong it is coming from where the head mounts to the block.
Click to expand...
The lack of crankcase venting would cause a leak but that would likely mean you also need a new head gasket.
 
Not necessarily. The oil is escaping from the pushrod galley's, not affecting the sealing off the compression around the cylinders or circulation of the coolant. I've had it happens several times when the oil seperator clogged up. Once the pressure is relieved, the problem goes away.
 
I checked the vacuum at the PCV valve. I had good vacuum there. When I installed the T I could not get vacuum to both sides. When I hooked the hose to the valve cover I could not get vacuum to the the hose to the air cleaner.

Right now I have the T blanked on the side of the air cleaner so the hose runs directly from the valve cover toe the PCV valve. I hope to get to take a test drive later.

Is there anything wrong with this setup until I can figure out what the problem is?

Thanks, Pete
 
As long as the PCV holds up, it sounds like the it's doing the same thing that the RG PVC kit does. That's using the intake manifold's vacuum to evacuate.
Yeah, I'd try it that way, what's the worse that could happen, maybe suck out a bit more oil than before ?
 
I hate to even suggest this but could the oil filter cannister be loose?
 
I checked the filter. It's OK.

I drove the car today and the leak is still there. I know there is plenty of vacuum.

I guess the next step is a head gasket???
 
Have you tried to degrease and use the powder trick? I would expect that would point you in the general direction of the leak. Could be something simple like a bad seal on the oil filter but might also confirm a bad head gasket.
 
I had a chance to check the car some more today.
I did try the powder trick and it still looks like the oil is coming from where the head and block mate.

I took the hose loose coming from the PVC valve to the valve cover and there is no vacuum for a second or two when I put my finger over the hose. I assume that is the way the valve is supposed to work. I changed the diaphragm in the valve and had the same results.

Could a bad oil cap cause the problem if it does not seal well enough for vacuum to build up in the valve cover??

Thanks again, Pete
 
Pete, where are you assuming there would be a vacuum source ? I'm a little fuzzy on where you expect to find it.
 
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