Lotus Elan

Twin Cam engine help

PostPost by: Jonesrp6 » Wed Feb 21, 2024 5:05 pm

Brilliant and thank you all

I will keep you update of the process!
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PostPost by: rgh0 » Wed Feb 21, 2024 9:58 pm

Twincam are only smokey when worn or not correctly assembled. What you need is data and expert analysis of that data. Smoke on acceleration certainly suggest rings or very over rich carbs which can affect the rings in turn by washing the oil off the cylinder walls with excess fuel.

The sort of things I would be asking if standing infront of that engine:

Are there any unusual noises, what do the plugs look like and what plugs are you using

what is the actual valve stem to guide clearance and is there any wear on either the guides or stems and is it within spec. What is the state of the cam bearings if excessively worn excess oil can end up in the head, flooding it and causing leakage down the valve stems especially on the exhaust side as it drains poorly

what is the piston to bore clearance, has the bore been poperly honed, have the rings been fitted correctly.

what head gasket are you using, though this is unlikely to be the issue if oil getting into all cylinders

what is you carb setup and jetting

what if any other modifications exist on the engine

Very hard to do this sort of analysis remotely so if you cannot do it you need to find someone with a detailed knowledge of twincams locally

cheers
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PostPost by: Jonesrp6 » Wed Feb 21, 2024 10:15 pm

Rohan, again many thanks

I will be running through all this with my engine guy this week

Really appreciate it
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PostPost by: rgh0 » Wed Feb 21, 2024 10:34 pm

One question I missed is how has then engine been run in to seat the rings properly ?

cheers
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PostPost by: Jonesrp6 » Fri Mar 22, 2024 7:27 am

Hi all

I have taken the engine to a lotus specialist who is recommending a full rebuild and rebore as oil is getting in all cylinders from the top

Not sure what was done in changing the rings to cause this but a real nightmare

I am being quoted about 7,500 for this. Seems very expensive for a relatively straight forward engine

Any thoughts or recommendations on who to use to get this sorted would be really appreciated

Thanks
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PostPost by: HCA » Fri Mar 22, 2024 8:26 am

7,500? Cheap enough for a full rebuild.

If you have this advice from a ‘Lotus specialist’ then why not use them…?
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PostPost by: berni29 » Fri Mar 22, 2024 9:57 am

Hi

Clearly if the engine has been rebuilt by someone who is competent at such things then it does not need rebuilding again. Look elsewhere for the issue. If it seems like guides you may be able to fit some sort of guide seal without engine disassembly (apart from cover & springs).

Sounds like a horrible experience, and hope you get it resolved.

All the best

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