Lotus Elan and Lotus Elan Plus 2 Forums

Could I have suggestions on the best method/product to use to seal the cam cover on the Lotus twin cam engine.

Thank you

I swear by making a re-usable silicon seal on the cam cover,thoroughly clean both faces,lightly oil the head face and apply a bead of low modulus silicon sealant on the cam cover face , place on the head, apply light pressure and allow to " go off" for as long as you can , trim as you wish ....

John

Buy a Cometic cam cover gasket and a sheet of nitrile rubber. Bond the Cometic gasket to the rubber sheet, then cut it out with a craft knife. This gasket seals perfectly and can be removed and replaced ad infinitum.
While you're at it, lightly countersink the stud holes to take o-rings. When the washers are tighten down on the o-rings, you will hve a perfect seal.
Dougal.

First off check your cam cover isn't warped....... If it is you will struggle with most methods.

Personally i'm using a cork gasket with a smear of Aviation sealer on both sides (the cam cover and head need to be immaculately clean and de-greased with brake cleaner) and some Permatex grey ultra on the half moons (use fresh rubber spring washers on the studs too every time you remove the cam cover).

I do it this way to stand a chance of getting it back of if need be, a member of my family decided to fit a Alfa cam cover without a gasket using RTV and literally couldn't get it back off. Was a running joke but never leaked

Just found this:
https://www.youtube.com/watch?v=ngXf0CBKlnQ

not for DIY I suppose ...

gherlt wrote:Just found this:
https://www.youtube.com/watch?v=ngXf0CBKlnQ

not for DIY I suppose ...

Whilst the concept is sound, replicating what the video shows is a different kettle of fish.

"Find an engineering company that has with up to date computer equipment"

That is probably not too difficult, there are tens of thousands of suitably equipped companies in the world so one might be closer than you think, finding one that will actually take on a one off CNC, scanning and milling job is the tough bit.

I would like to be proved wrong but my experience over the last few years is that most (UK) companies are just not interested in one-offs

Ian

I'm using the standard cork gasket with aviation sealant no.3 on the head side. Working well so far!

john.p.clegg wrote:I swear by making a re-usable silicon seal on the cam cover,thoroughly clean both faces,lightly oil the head face and apply a bead of low modulus silicon sealant on the cam cover face , place on the head, apply light pressure and allow to " go off" for as long as you can , trim as you wish ....

John

Have to agree.
Went with this method some time ago and have had the cover off a few times since.
Popped off each time without trouble and hasn't leaked.
The other good thing is that high temp silicon for gaskets is available everywhere, and isn't that expensive.

Ralph.

Elanman99 wrote:

gherlt wrote:Just found this:
https://www.youtube.com/watch?v=ngXf0CBKlnQ

not for DIY I suppose ...

Whilst the concept is sound, replicating what the video shows is a different kettle of fish.

"Find an engineering company that has with up to date computer equipment"

That is probably not too difficult, there are tens of thousands of suitably equipped companies in the world so one might be closer than you think, finding one that will actually take on a one off CNC, scanning and milling job is the tough bit.

I would like to be proved wrong but my experience over the last few years is that most (UK) companies are just not interested in one-offs

Ian

I had a look at his previous video https://www.youtube.com/watch?v=4RxDZfULui0 and was not quite convinced by his approach of loosely nailling a flat sheet metal in hope to butt two joint strusses : a moderate load will see the plate slip till nails reach the end of their slot... the consequence of this technique used on a roof - or anything actually - is not going to be pretty.



that kind of thinking (or lack thereof) does not encourage me to investigate much further...

Chrispy wrote:I'm using the standard cork gasket with aviation sealant no.3 on the head side. Working well so far!

I'm using the standard cork gasket with aviation sealant on the cover side, and it's working well so far too

nmauduit wrote:

Elanman99 wrote:

gherlt wrote:Just found this:
https://www.youtube.com/watch?v=ngXf0CBKlnQ

not for DIY I suppose ...

Whilst the concept is sound, replicating what the video shows is a different kettle of fish.

"Find an engineering company that has with up to date computer equipment"

That is probably not too difficult, there are tens of thousands of suitably equipped companies in the world so one might be closer than you think, finding one that will actually take on a one off CNC, scanning and milling job is the tough bit.

I would like to be proved wrong but my experience over the last few years is that most (UK) companies are just not interested in one-offs

Ian

I had a look at his previous video https://www.youtube.com/watch?v=4RxDZfULui0 and was not quite convinced by his approach of loosely nailling a flat sheet metal in hope to butt two joint strusses : a moderate load will see the plate slip till nails reach the end of their slot... the consequence of this technique used on a roof - or anything actually - is not going to be pretty.

nailed wrong.jpg

that kind of thinking (or lack thereof) does not encourage me to investigate much further...

Having seen that picture of the plate nailed to the joists, I would not waste my time watching the video.

Apart from not putting the nails at the extremities of the slots, the nails have been placed in a line along the length of the same grain significantly increasing the chances of splitting the wood.

Getting back on thread, the cam cover modification. the narrator did not explain why is was necessary to meticulously clean and degrease the cover before it was machined.

Ian

nmauduit wrote:

Elanman99 wrote:

gherlt wrote:Just found this:
https://www.youtube.com/watch?v=ngXf0CBKlnQ

not for DIY I suppose ...

Whilst the concept is sound, replicating what the video shows is a different kettle of fish.

"Find an engineering company that has with up to date computer equipment"

That is probably not too difficult, there are tens of thousands of suitably equipped companies in the world so one might be closer than you think, finding one that will actually take on a one off CNC, scanning and milling job is the tough bit.

I would like to be proved wrong but my experience over the last few years is that most (UK) companies are just not interested in one-offs

Ian

I had a look at his previous video https://www.youtube.com/watch?v=4RxDZfULui0 and was not quite convinced by his approach of loosely nailling a flat sheet metal in hope to butt two joint strusses : a moderate load will see the plate slip till nails reach the end of their slot... the consequence of this technique used on a roof - or anything actually - is not going to be pretty.

nailed wrong.jpg

that kind of thinking (or lack thereof) does not encourage me to investigate much further...

Probably not being entirely fair to the bloke as these plates aren't merely strips of steel with holes in them.
If you Google "gang nails" you'll see how they work.
The slots are where the metal has been punched down to form a nail so the plates are essentially multi nails, and, looking at the number of barns in this part of the World that are held together with them, they are pretty strong.
A few nails hold them in place but not as many, or in the strange pattern, as this example.

[quote="reb53"
Probably not being entirely fair to the bloke as these plates aren't merely strips of steel with holes in them.
If you Google "gang nails" you'll see how they work.
The slots are where the metal has been punched down to form a nail so the plates are essentially multi nails, and, looking at the number of barns in this part of the World that are held together with them, they are pretty strong.
A few nails hold them in place but not as many, or in the strange pattern, as this example.[/quote]

precisely : did you check that vid? the idea he promotes there is to grind off all the nails of the nailband, and to replace them by regular nails, so that they can be nailed in one by one... no consideration whatsoever of the structure of the nailband (mails being part of the band), the integrity of which being what gives strength to the assembly.

Too many videos to watch!
I agree, idiot....

A few years ago these cam cover gaskets were available. I'm pretty sure that Ray at R.D. Enterprises stocked them at one time but I don't see them on his website now. It would be worth calling him if you want one.

Apologies for the poor picture but if you look closely you can see that it has a silicon bead embedded in the gasket material. It sits slightly proud, to provide a good seal.

I purchased it back in 2013 and haven't fitted it because my current rubberized cork gasket (also from Ray) is working fine. A guy was circulating around the twin cam owners at Lime Rock, selling them.

I've no idea whose part number is on it, but it was apparently made in Italy. It seems to be a nice piece of work.

Nick