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TR6 Oil Leak found! Now what?

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Gliderman8

Gliderman8

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I've spent the last two driving seasons trying to track down the source of a oil leak.... yes, I know that all British cars of this era leak, but this is a bad one.
I've straightened the oil pan and used a new gasket.... no change
New silicon rocker cover gasket.... no change
New seal on the timing chain cover.... no change
Today, I found it.... there is oil shooting out of the riser tube where the dipstick goes... eeek!
I'm thinking it is related to the oil relief valve.... is it possible the PO put a stronger spring in? With nothing to compare the spring to, is there a way I can tell?
And the big question is.... Am I on the right track thinking it's the oil relief valve?
Oh yeah... one more thing- When I start the car the oil pressure is reading 100psi until it warms up then drops to around 50psi
Your thoughts please.....
 
Do you have the little cotton/foam stopper for the stick?
 
I don't think so don... do you think it could be as simple as that?
 
Last time I had anything like that, Elliot, it was because of inadequate crankcase ventillation.. The hose from the valve cover to a separation canister had emulsion inside which reduced the effectiveness. After having to clean that line out twice in too short of a period of time, I did away with the whole affair and vent the valve cover directly to a carb, pretty much as the original design.
If you don't have all that plumbing to deal with, then maybe it's excessive blowby past the piston rings..or maybe it is just lacking that felt seal between the dipstick and the dipstick tube.
 
Ken... I just went outside to check the hose coming off of the valve cover.... the hose has some "T" fittings and one part of the hose goes to the carbon canister next to the radiator, but there are two more lines each connecting to the carbs. I pulled each hose off where it connects to the carb and BOTH carbs have little plastic domed covers over the carb inlet.... essentially they are blocked off. The hose's are connected to each carb, but the plastic cap is blocking the holes.
Should I remove the caps? Why are they there?
 
I second poolboy. My TR6 "marked" its territory regularly only by blowing oil by the front seal, which otherwise was ok, due to canister. Dealt with that,no more leak.
 
Here's photo of the caps on each carb:
carb plug 003.jpg


How do I deal with the canister? What needs to be done?
 
For mine, to test it, I simply pulled the hose from the top of the canister to allow it to breathe, drove it around, no more "marking territory" You can order new cannisters I tried just cleaning the filter but that wasn't sufficient. If your hose is plogged you need to replace.
 
Those really aren't "caps" per se, Elliot. They are adaptors so the hose from the valve cover will fit onto those "evacuation ports" on the carbs.
At the very least connect the valve cover vent to one of those nipples and cap (seal) the other one.. On the carb you cap, you MAY have to turn your mixture adjustment about 1/8 to 1/4 counterclockwise to compensate....but do some driving and check your spark plugs for color..no use in assuming they will need any adjustment.
If you have the cannister you could go ahead and make the connections as shown in the Moss catalog for instance.
But, having eliminated most of that emission stuff myself, I've found the set up that I show pictured to be perfectly satisfactory in relieving crankcase pressure.
 
Thanks for the photo Ken... that helps a lot. I'll have to get some smaller diameter hose in order to make the connection to the carb. I sure hope that stops the oil from coming up the dipstick tube. Since I don't have the felt seal on the dipstick, I'll order one tomorrow.
Thanks again for all the good suggestions.
 
The purpose of the adaptor in your picture is so that the same hose will fit both the valve cover nipple and the carb, Elliot,
 
You weren't kidding
You don't have the seal there.
Well that will help...until it gets oil soaked
 
poolboy said:
The purpose of the adaptor in your picture is so that the same hose will fit both the valve cover nipple and the carb, Elliot,
Click to expand...
I get that the adapter (cap) allows the hose to fit, but since there is no hole in the cap the hose cannot vent into the carb... what am I missing?
 
OK, that makes sense now. I see that TRF part #155148 (AZ80) is no longer available. Can I just cut the top of the cap off of the one I have?
I'll check Moss to see if they have it.
 
Make sure the hose fits tight around the cap so the carb won't be sucking air instead of from the valve cover.. You may have to use some silicone RTV for a good seal without having an "official" adaptor.
I measured the vacuum from that port a while back and it's not very much compared to manifold vacuum so the hose needs to be air tight around the adaptor.
 
Thanks again Ken... I'll get the hose sealed properly. I'll also check with Moss to see if I can get the adapter.
 
Elliot,here's how I vented my valve cover. 7/16 od x5/16 id vinyl tubing and a Y vacuum fitting to the valve cover.Triumph valve cover venting 002 (Medium).jpg
 
Thanks Casey... I disconnected the line running to the canister and it seems to have drastically cut down on the leak. Tomorrow I'll look into getting some fittings and do the routing of the hose's correctly.
 
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