Lotus Elan

Hole in Exhaust Manifold?

PostPost by: Cinbearcat83 » Thu Jan 09, 2025 11:47 pm

My brother and I got the 1973 Elan+2 S130 running last summer. It has the Big Valve engine. After running it a while, we noticed an exhaust leak in the engine bay. After taking a closer look, I discovered a "hole" in the bottom of the cast exhaust manifold. I have two photos attached. The hole looks like it has been welded at one time or it is there intentionally. Has anyone run across this before? Thanks, Kevin
Attachments
IMG_8858[1].JPG and
Close up using a mirror
IMG_E8855[1].JPG and
View from underneath vehicle
Kevin

1972 Elan +2 S130
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PostPost by: rgh0 » Fri Jan 10, 2025 12:34 am

I presume you have a stromberg head that orifinally came with the cross over tubes to heat air at idle on the exhaust manifold. Most of these cross over tube systems have been removed now in the US and I would replace the cast manifold with tubular manifolds that were used on non Federal cars
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PostPost by: Cinbearcat83 » Fri Jan 10, 2025 2:02 pm

Thank you for the insight. Yes, I do have the Stromberg carburetors. The cross-over tubes were in a box that came with the project car. So the hole is part of the emissions system - that's helpful. I have been considering replacing the exhaust with a more free-flowing system. Does anyone have any recommendations?
Kevin

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PostPost by: tonyabacus » Fri Jan 10, 2025 4:14 pm

Kevin
I think you may be in the wrong place.

Place an advert in the For Sale and Wanted where it is likely to attract more attention with those that may have a manifold
Tony
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PostPost by: andyelan » Fri Jan 10, 2025 4:41 pm

Hi There

The hole is where the runner was cut off after the manifold was cast, there's a similar witness mark on the cast manifold of my Europa.

If there actually is a hole in the manifold, then I agree with Rohan that sourcing a tubular manifold is the best bet, however, I would suggest you double check that the leak is definitely coming from the hole and not the joint. On my Europa I was always having problems with leaks from between the manifold and the down pipe flanges and any gasket I tried would simply blow out (I don't think the three 5/16" studs provide enough clamping force across the joint). In the end I had to take every thing apart, file the joint faces perfectly flat, then fit a solid copper gasket and bolt everything together with steel "Stover" nuts. Even now, I still have to check and nip up the nut every six months or so.

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Andy
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PostPost by: Cinbearcat83 » Sat Jan 11, 2025 3:19 pm

Thanks for the information. I am going to look into replacing the stock manifold with a header.
Kevin

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