smoke........

[alfert]

I have recently completed a "complete" restoration, everything is new, on a 66 Elan Coupe. The car is near perfect but I am trying to find an oil leak and the reason for some serious smoke at start up but only after car sits for a couple of weeks. There is oil on floor at rear of pan and it also appears to be coming off of the down pipe at the "Y" pipe. In fact I almost believe that oil is getting into the Y pipe as I can't believe the guides are leaking at least not that much. The engine is totally rebuilt by a good guy. Has new everything. Great performance, no smoke, proper oil pressure, etc. I run Brad Penn 20/50. I am missing something simple, I hope....... I am getting ready to sell it and want to be sure it is right. Any help is greatly appreciated.
Thanks,
Brian,

[oldelanman]

Hi Brian,

Do you park the car on a slope ??

Have a look at this old thread.........

elan-archive-f16/exhaust-side-oil-drainage-t12403.html


Rohan said this......

"I understood the cross drilling was introduced to stop smoking
complaints when the car was parked on a slope with its nose steeply
uphill. Over night the oil would drain into the exhaust through the
rear valve guide which was below the pooled oil level if the hill was
steep enough. This resulted in a large cloud of smoke on startup. "

[alfert]

No, the car is parked in the garage. There is oil cooking off the exhaust Y pipe and coming out of the tail pipe as well. If it sits for a day or two the is just a little smoke at start up. If it sits for a couple of weeks it is a problem??
Brian

[StressCraxx]

The half moon shaped cam bore plugs have a tendency to shrink from the heat and leak a bit from the exhaust side rear of the head. The cork gasket weeps, no matter what. The other three plugs leak too! The oil finds its way down the back of the engine and drips on the top of the "Y" collector. When you start it up, the exhaust heats the oil on the Y and it smokes til it cooks off.

The oil out the exhaust pipe is from the oil that makes its way past the unsealed valve guides into the engine. It burns off on startup. It does no harm, even if your car sits for months(but you should take it out to play to let it know you care). Its just part of Lotusing. Some people have put in valve guide seals to prevent this. I would not bother until it was time for a full rebuild, if ever.

For me, I am just grateful it always starts!

[spanner]

Its just part of Lotusing.

Yup, or flying behind a round engine....... http://www.youtube.com/watch?v=-XVgCqsH ... 7A595C86B0

Jim

[alfert]

You guys are not helping very much...... maybe I just have to live with it, but I am not ready to give up.

[65 Lotus]

Pull the exhaust manifold after a run (after it cools), let it set, and see if it's coming out the guides and if so which cylinder.

If not, move on to the next possible scenario.

[fatboyoz]

Brian,
Adjacent to, and above, the forward and rearmost exhaust ports is a plug that screws into an oil gallery in the head. These can leak. If your exhaust gasket is not sealing completely, and the plug is leaking, I imagine that oil could make its way into the manifold. The aft one could also drip onto the outside of the manifold as well. Not saying that this is your problem, but worth a look. I resealed mine, after unsuccessful attempts with fibrous and copper washers, with high temp' Viton O rings.
Regards,
Colin.

You guys are not helping very much...... maybe I just have to live with it, but I am not ready to give up.

[bast0n]

The half moon shaped cam bore plugs have a tendency to shrink from the heat and leak a bit from the exhaust side rear of the head. The cork gasket weeps, no matter what.

Nonsense! Put it together properly and these items do not leak.

On the other hand I have had a porous head that leaked oil through the head casting onto the exhaust pipes. Oh yes, expensive................!

[StressCraxx]

The half moon shaped cam bore plugs have a tendency to shrink from the heat and leak a bit from the exhaust side rear of the head. The cork gasket weeps, no matter what.

Nonsense! Put it together properly and these items do not leak.

On the other hand I have had a porous head that leaked oil through the head casting onto the exhaust pipes. Oh yes, expensive................!

Would you consider explaining to all of us how to put it together properly?

This car 45/7279 has owned me for more than 32 years. About 3000 miles after replacing the gasket and sealing everything up with RTV, the oil starts to seep through. The valve cover surfaces are old, but flat within .010" across. The leak path is between the edges of the bore plugs and the gasket

I put the valve cover on after the water pump kit conversion a year and a half ago, about 3000 miles. The valve cover and bore plugs held well until a trip to the Monterey Hysterics in August. The trip included 240 miles of cruising at 75mph, some trips into Carmel, Pebble Beach, and a tour along Highway 1 to Big Sur. A whole year and a half of clean garage floor was wonderful!
This winter the valve cover comes off for a clearance check. Will replace the gasket and use your method.

Regards,
Dan Wise

[prezoom]

My cam cover leaked from day one. After trying all of the various sealants, and still leaking, I tried something else. I put the cover on a nice flat surface and with a feeler gauge, I started measuring gaps. After a very short time, I found I didn't need the gauge, because the cover had sections with enough space between the cover and the surface you could walk through.

I used some JB Weld on the low spots, threw down some cling wrap and set the cover on top with some weight to hold it down. Then I used some spray adhesive to stick down some wet or dry sand paper to the flat surface and with a figure eight motion, lapped the cover until it was dead flat. That and some home made cam cover "O" ring washers for the hold down studs, and the engine has been dry on top ever since.

Rob Walker
26 4889

[StressCraxx]

Rob,

I did that with my Formula Ford alloy valve cover last summer. I don't have a lapping plate big enough so I used the garage floor. I used a magic marker to mark the gasket surface and worked it across the floor to find the high spots. It appeared to have a twist in it with high spots on opposite corners! I used the smooth concrete floor again until the ink was all worn off. It doesn't leak and looks much better than the old tin valve cover.

Sounds like a task to add to the winter work list....

[Jeff@Jae]

If you suspect the cam cover gasket remember that if it's the standard cork cam cover gasket it will need to be gently re torqued numerous times before it eventually settles. You'll note the cam cover nuts will be rather loose after a little while until they've been re tightened several times. Do not attempt to use too much force, just snug them up.

[prezoom]

I have a very nice lapping plate, I generally use it for the top of blocks to make sure they are dead nuts flat. Also use it to check cylinder heads for flatness. But, it was a little too small for the cam cover. I have a roll around table with a steel top that is about as flat as it gets. Gluing the sheets of sand paper down on the table worked quite well. Just about anything flat would work, like your garage floor.

The cam cover washers were made from a round of 1/2 inch aluminum, bored back in the lathe with an end mill, just enough to leave the "O" ring proud, and then parted off. Bought some Viton "O" rings that slipped inside the counter bore and were tight over the studs. The engine has been driven at least 6k miles and is still dry as a bone on top. Still working on the odd drip or two from the rest of the engine.

Rob Walker
26 4889

[ianf]

Hi I had a white whispy smoke appearing on the exhaust side of my engine when the exhaust manifold gaskets needed replacement. The colder it was the worse the effect as I suppose more condensation in the engine.

Worth a mention I hope?

Cheers, Ian