Engine rebuilding

[rideaway]

Hi all
After buying a Lotus Elan a little hastily, because it was a price I could pay, I had a first shock with the origin of the car. https://lotuselan.net/forums/viewtopic.php?f=19&t=51430
The second shock came with the condition of the car, everything works but nothing properly. 50 years of DIY have been there!
I tackle the reconstruction of the engine, I have experience of engines, but either diesel tractors or modern motorcycle engines, but I have hundreds of questions for Twincam specialists.
The following problems were noted when disassembling the cylinder head
- Wear of valve guides, to be changed
- Wear of exhaust followers sleeves, to be changed
- Exhaust followers wear, to be changed
- Cracks between the spark plug and the intake valve on 2 cylinders
- Deformation of the parting plane corresponding to the timing case
- Epoxy clogged cracks on the ''timing case parts’’
- Paint to plug porosities peeling and contaminate the entire engine
The rest of the head components aired in good condition and the cylinder head gasket was not blown out.
Do you think a new cylinder head is necessary, taking into account the major work that needs to be done?
The cylinder head number doesn't correspond to the engine or the car. It's an early Weber cylinder head with follower sleeves only on the exhaust.
The aim is to make a reliable road engine, not one for racetracks (which don't exist in Switzerland!).
Regards
Stéphane

[HCA]

If you have cracks in the head - especially between plug and valve seat, then yes, you need to change the head.

From what you describe, you might do well in acquiring another engine from a reliable source and starting with this. There are engines to be had, you just need to look for them and establish a truet that they are ok. Look back a few pages on the forum - someone was selling a newly built one.

If you can wait a year or so, I will have a complete 'Big vlave' engine and gearbox with all ancilliaries for nominal money...

[gherlt]

Depending on what the car is meant to become (road, fast road or race), in case of "road use" I would certainly consider asking CTM (London) about their opinion. They repaired my cyl head - which was considered scrap by many with exception of Brian Buckland - and for a lot less money than anticipated. Of course, in my case, the cyl head was original to my car (some effort for originality) and the car will be "slow road", original 105bhp and no need for more.

[2cams70]

Small cracks usually don’t kill a head. What does kill a head is if it’s gone soft. Sometimes receding of the head bolt seating area indicates this has occurred. Best to get the head checked for hardness before doing any major work on it.

[rideaway]

Thank you for your answers.

I'm interested in Hal's proposal, you can contact me by PM.

For CTM London, after a Google search, they closed in January this year!

I don't think the head has gone soft, but in Switzerland the cost of working on the engines is frightening. You have to be a banker to pay for it. There's too much money in the classic car world in Switzerland. There's also a problem with the spark plug threads, which have been repaired with ''Helicoil'', but not very well. There's a lot of material removal in this critical area.

[rgh0]

Without more detailed photos and measurment it is hard to say whether the head is economically repairable. But none of the issues listed usually cannot be fixed at reasonable cost and much less than a new head. I agree that the first step is to check the head hardness before engaging in major work. Visual recession of the head bolts in a warning sign of a soft head but you really need to get it tested

The small cracks between the plug and inlet seat are common and generally not an issue.
Helicoiling the plug threads can be successfully done as the plugs seal on the washer not the threads but if poorly done may need replacement with something like Timeserts which have a larger O/D and can replace a helicoiled thread..
Worn follower sleeves can be honed out and oversize followers fitted.
Worn valve guides can be replaced or fitted with K- line liners
Cleaning / remachining / replacing other components due to porosity or distortion is routine in any engine build

I am currently staying in Germany and visiting Hal in Southern France in a couple of weeks time to have a look at the Twin Cam he has been building. I was planning on travelling back to Germany through Switzerland and may be I could stop and have a look at your engine if you would like?

cheers
Rohan

cheers
Rohan

[HCA]

There you are Stephane - an offer you should grab with both hands! You will not a better one!

[rideaway]

Thanks Rohan, that's nice of you.
I'd hate to inconvenience you and have you make a diversion for me.
But if you're feeling up to it, there's a meal and a beer waiting for you. Although I'm bad at English, it's always interesting to talk to Lotus fans.
I'm in Bex at the eastern end of Lake Léman. Close to the start of the historic Ollon-Villars hill climb, where several Lotus Elans raced last summer.

[661]

Thanks Rohan, that's nice of you.
I'd hate to inconvenience you and have you make a diversion for me.
But if you're feeling up to it, there's a meal and a beer waiting for you. Although I'm bad at English, it's always interesting to talk to Lotus fans.
I'm in Bex at the eastern end of Lake Léman. Close to the start of the historic Ollon-Villars hill climb, where several Lotus Elans raced last summer.

How strange. We have a place in Valais, La Tzoumaz.

[rgh0]

Thanks Rohan, that's nice of you.
I'd hate to inconvenience you and have you make a diversion for me.
But if you're feeling up to it, there's a meal and a beer waiting for you. Although I'm bad at English, it's always interesting to talk to Lotus fans.
I'm in Bex at the eastern end of Lake Léman. Close to the start of the historic Ollon-Villars hill climb, where several Lotus Elans raced last summer.

I am sure your English is better than my French.

Bex is actually on the route we were planning to use to get back from Toulouse to Worms in Germany via Bern so no inconvenience to stop and have a look at your engine. I always enjoy talking Lotus and having a beer

I was planning on leaving Toulouse on the morning of 22/6 and stopping somewhere overnight in Switzerland in your general area so we could meet up the evening of 22/6 or morning of 23/6 if that suits you. I will PM you with my contact details

cheers
Rohan

[TWebb]

One of the reasons I love this forum. The help people offer to one another is amazing.

Thanks Rohan for giving me a smile this morning and continued faith in the human spirit.

[rideaway]

One of the reasons I love this forum. The help people offer to one another is amazing.

Thanks Rohan for giving me a smile this morning and continued faith in the human spirit.

Rohan always has the right answers for everyone's problems! He answers questions calmly and sympathetically.

How strange. We have a place in Valais, La Tzoumaz.

Graeme, la Tzoumaz is a beautiful place, I go there from time to time when I do the Croix de Coeur pass on my motorbike.

If you can wait a year or so, I will have a complete 'Big vlave' engine and gearbox with all ancilliaries for nominal money...

Hal, I'm interested in your proposal. Do you have any more details?

I was planning on leaving Toulouse on the morning of 22/6 and stopping somewhere overnight in Switzerland in your general area so we could meet up the evening of 22/6 or morning of 23/6 if that suits you. I will PM you with my contact details

While I'm waiting for Rohan to pass by, I'm going to put the engine to one side and tackle the gearbox!

[HCA]

I am, for the fun of it, building a new twincam engine from new parts where possible. For the small outlay, I shall add a Ford box to it.

This means that I will have a complete engine, box and everything associated with doing nothing. Rather than leave it to fester in a corner, I shall probably pass it on for a token price. It is out of a 73 Plus2 though, And it will be a year away (I guess though I vould be persuaded to take it out earlier…

[MACCA.GLM]

Hi Stephan

It sure is a small world as 666 said he has a place in la toumaz.I also have palace in Crans Montana and regularly drive down past Bex on the motorway

I was wondering if you have more info on the hill climb at Ollon as I would love to bring my sprint down for a go.

Good luck with the engine

Regards
G

[john.p.clegg]

Stephane

you have mail....

John