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Not the usual oil leak

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mylesw

Jedi Hopeful
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Hello

My BT7 has a mysterious oil leak which I'm hoping someone can help me with. During a recent 200 mile trip across Texas the oil level was reduced from almost max to below min on the dipstick. The oil is not coming out from the exhaust but is exiting the engine somewhere else with a lot of it ending up on the inside of the hood and in the channels around the engine bay and a lot more of it is finding its way onto the outside of the exhaust and under the car.

The oil that ends up on the exhaust is being burnt off giving me a nice big cloud of smoke to follow me around. This smoke is intermittent and I was unable to correlate it with anything I was doing except to say that it generally does not happen below 60 mph. Other things: oil pressure is good - just over 40 psi at 3000 rpm warm and the car is fitted with a vent can (by previous owner) so a line goes from the rocker cover to the vent can and then from the vent can to both the air intake and the block.

I am currently suspecting this oil is leaking out from the tappet covers only because there is some oil on the block around these and I cannot see anywhere else on the engine with any telltale signs that it is the culprit. Before I start to dismantle my engine, does anyone have any ideas what could be the cause of my oil leak or has anyone experienced it before? Thanks for you help.

Regards

Myles
 
Hi Myles, Take all that PO installed venting off the car and restore it to its original condition. I think what you are experiencing is excessive crank case pressure, caused by a blockage in that venting system.--Fwiw--Keoke
 
I think Keoke is right. While you are working on the plumbing, you can easily pull those tappet covers, replace gaskets and use some hylomar gasket sealant on them. Do the same with the valve cover gasket (and you might want to glue the valve cover gasket to the head to provide an oil 'dam effect' whenever you have the valve cover off). When you have the valve cover off it's good to check the flow of oil from the rocker arms. At idle and at elevated rpm's the oil should only be dripping out of the holes, not geyers shooting out. Let us know what you find .. the rocker arm assemblies can be rebuilt.

Cheers,
John
 
If your rocker arm is old and worn, you may be pumping lots of oil up top which will add to the oil available to leak from the rocker cover. This can be determined by removing the oil filler cap and seeing if you are getting gysers from the rockers. It should just be a drip drip. If you have gysers or get oil in your eye you need to send the thing to RAS for a rebuild.

To seal the rocker cover consider gluing a fresh dry cork gasket to the rocker cover off the car. Use a clean flat surface to allow it to dry overnight. The sealant to use for the gasket to cover gluing process is the kind that will dry, blue RTV or some such.

Kyoke recommend using Hylomar but this is no longer available. The substitue is Selemar and is black non drying, very similar to hylomar.

By using this you will be able to reuse your gasket over and over.

Also consider getting a half gallon of simple green cleaner and clean up that oily engine bay. Now look again for leaks.

hope thsi helps.
 
Hi John, there is reportedly some concern that Hylomar is a hazardous material since it contains Methylene chloride.--Fwiw---Keoke-?
 
Yup .. very hazardous .. please send all your partially and unused tubes of Hylomar to me for immediate hazmat processing. /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
 
The distribution on Hylomar has always perplexed me--some NAPA stores carry it and others say they never heard of the stuff.

It is definitely fuelproof--I made the mistake of getting some in my tank when attempting to seal up the fuel sender. About six months later I extracted a glob of Hylomar from the inline fuel filter (installed between the tank and fuel pump). I cut the filter open and the Hylomar had the same consistency as when it came out of the tube.
 
John Loftus I couldn't find any info on Selemar. Sure that's spelled right?[/quote said:
OOps Mea Culpa.

Sellador Flexible. Marked 2A from Permatex

Mike, You crack me up. You have a bit of mad scientist in you eh? Perhaps I should put some sellador in a teaspoon of petrol and see what soup it makes? I am using it on my fuel senting unit.
Click to expand...
 
Mike, You crack me up. You have a bit of mad scientist in you eh? Perhaps I should put some sellador in a teaspoon of petrol and see what soup it makes? I am using it on my fuel senting unit.
--------------------------
Inquiring minds want to know....

Actually the whole episode was precipitated by my trying to reuse an old cork gasket which was a stupid and non-productive shortcut. Nothing works like a fresh one.
 
Michael Oritt said:
Actually the whole episode was precipitated by my trying to reuse an old cork gasket which was a stupid and non-productive shortcut. Nothing works like a fresh one.
Click to expand...

Yup. But Hylomar works great on those new gaskets too. I just put a dap of the Hylomar between thumb and index finger and apply it to both sides of the gasket at the same time, rotate the gasket so it has just a thin smear of sealant on the surfaces. No gobs .. no problemo. /bcforum/images/%%GRAEMLIN_URL%%/grin.gif

Cheers,
John
 
All

Thanks for you suggestions on how to fix my leak. I removed the vent can and replaced with the original set-up. I also had a look in through the filler cap to see if I could see any oil spurts - all looked good so I thought all was sorted. Then on my next trip on the freeway I got the smoking again. So I removed the valve cover and now I see the odd spurt coming out from two of the rockers near the back of the engine. Enough to leave spots on my paintwork. So looks like I have to rebuild the rocker shaft. Can someone let me know what this entails - should I just replace the bushes or replace the shaft too? Thanks for you help.

Regards

Myles
 
Hi mylesw,
I would recommend sending the rocker assembly to Rocker Arm Specialists . They list a rebuild at just over $200. I’ve never heard a bad thing about this company, and I’m a happy customer myself. I didn’t get a rebuild though, I purchased the roller rockers. Nice guys too.
 
Rocker Arm Specialist, 19841 Hirsch Court, Anderson, CA 96007, 530-378-1075, rebuilt mine about a year and half ago. I believe it was only about $150 then. Had it back and in the car in about a week.
BE CAREFUL when removing and reinstalling the oil feed tube to the rocker arm. The threads can be stripped very easily. As I recall when reinstalling, fit the oil feed tube but do not tighten until the rocker arm is fitted and tightened. Then carefully tighten the bango bolt.
 
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