Serious trouble V8

[Giniw]

2 hours ago, MD355 said:

He told me it has to do with the poor quality aluminum Lotus used in their design of the block...

Does he happen to know which aluminium alloy Lotus used? It could be interesting to know!

Edited October 17, 2019 by Giniw

[sailorbob]

It's LM25TF, an alloy commonly used for blocks and heads (and road wheels).

[Giniw]

Thanks, actually it was more a sarcasm than anything else as I suspect not any mechanic has your knowledge and I am a bit tired of mechanics who always justify problems on a car for an original poor design when it's so very often because of the previous owner or mechanics which butchered the car ... (not speaking specifically about Lotus here)

Edited October 17, 2019 by Giniw

[MD355]

You are absolutely right !!! My mechanic is making a fuss about it because he is used to working in more modern cars and the Lotus V8 is giving him a hard time... But he is a great mechanic with lots of knowledge, so we just joke about it...

More photos : 

[mike_sekinger]

Both the block and cylinder heads are made aluminium alloy LM25TF (fully heat treated LM25)

https://www.gutter.co.uk/wp-content/uploads/2018/05/LM25-ALUMINIUM-CASTING-ALLOY1.pdf

A lot of the pitting is coming from cases where either incorrect coolant is used or that the coolant has not been replaced at the correct intervals.

[mike_sekinger]

Sorry to make the observation, but why has the engine builder elected not to install the cylinder heads when sealing the liners?  That is not an appropriate way to clamp the liners in place.....

[Barrykearley]

Looks like the liners are just sat floating - surely isn’t correct 

[mike_sekinger]

I'm struggling on this thread - you want the "ultimate in reliability" and go to the trouble of balancing and purchasing nice forged pistons, but you are having your mechanic re-use your old liners and without any glaze busting/re-surfacing?  Why is that?  What piston->cylinder clearance do you have across those liners?  Has that been measured?  As previously highlighted, the OEM pistons/liners are provided in two size grades, you could end up with wrong clearance when installing the piston. Same with the ring gapping that would have been necessary.

I don't want to come across as being a critical old fart, but some of these decisions make no sense to me.

Edited October 18, 2019 by mike_sekinger
corrected text

[MD355]

I appreciate your help... I have asked him about the clearances and he will get back to me...

If you look closely the cylinder liners are held into position by some metal sleeves I believe...

My mechanic told me no need to replace sleeves...

 

[mike_sekinger]

I'm out of this one.

[910Esprit]

12 hours ago, Barrykearley said:

Looks like the liners are just sat floating - surely isn’t correct 

That was my thought too.  I was advised to ensure the entire liner surface is sealed into the block (admittedly on a 4 pot).  Presumably it reduces the risk of 'fretting' or movement during heat cycles  

Edited October 18, 2019 by 910Esprit

[MD355]

38 minutes ago, mike_sekinger said:

I'm out of this one.

I hope I haven't offended anyone... I am doing my best to understand how this build is supposed to be done...

[MD355]

Guys new update :

I got the numbers

The piston number is 82.941

and the cylinder sleeves 82.997

How do these numbers sound ??

Mike, for the sleeves there was glaze busting/re-surfacing involved indeed !!!!

[MD355]

more photos of my build

Tomorrow we will be placing the cylinder heads and will time the engine.. I could not find an new chain that drives the timing gear... Do you think it is ok to keep the old chain ??

Edited October 22, 2019 by MD355

[sailorbob]

On 18/10/2019 at 12:22, MD355 said:

The piston number is 82.941 and the cylinder sleeves 82.997. How do these numbers sound?

If the pistons are CP Carillo ones then the bores are minutely too small according to the specs. Mike gave on page 2.

[MD355]

Based on Mike’s spec the bores should be 82.9996 vs mine that are 82.997 mm. The difference is 0.0026 mm ... I am no mechanic but this seems to me pretty small number...

[Barrykearley]

Chap - there’s a spec for a reason - to doubt or argue with the numbers will achieve on thing only and that’s financial loss

[sailorbob]

I personally wouldn't worry about 1/10000" difference, I doubt the average mechanic is using equipment that can measure to that accuracy. My reply about the specs. was essentially just to answer your question.

[MD355]

Thank you !!! I had completely missed Mike’s comment on page 2 !!! 

[ramjet]

Hi Makis,

I don't have much to add with regard to how you are going about things, but I would suggest that you do pay some heed to Mike S.

He has quite a bit of experience with exactly what you are doing.  

I will admit that I would have used the heads to hold the liners in place after adding sealant and installing them. I doubt I would have been happy with the method used in the photos above. If there is any misalignment or the potential for errors with liner nip, it may well end up causing you grief with one/two head gasket sealing/failures.

[MD355]

You are right, I do pay attention to everything said on this board and particularly Mike S that is very knowledgeable.... I convey everything, including all the questions to my mechanic... At the end of the day he takes responsibility of his work !!

He seems confident he is doing it right... So I hope my build is successful and I finally get to enjoy my car without problems...

 

[MD355]

Progress...

[mike_sekinger]

Sorry - I can't help it.... it seems to be a joke.   Why is he fitting cam covers and wiring the plugs before setting the cam timing?  He's going to need to clamp or hold the camshafts to tighten the pulley's.     Please, please get your mechanic a copy of the Service Notes for the 918 engine before it is too late.

[MD355]

You are right and I really appreciate your help!! My mechanic is a little unorthodox, but he is confident he knows what he is doing !!

I will go tomorrow to check on him...

[Barrykearley]

😱😰 bloody hell - mikes right - get him a copy of that engine manual quick.

theres a whole heap of very expensive parts that could be ruined if he’s not very careful.