Engine Rebuild/Upgrades

[99ESPRIT]

6 hours ago, v8GTmac1 said:

new rod and mains Yes from Jaeparts,  idk where you are located but these guys are in California.

Pistons did not have any damage and the rings looked good up close visually I guess you have to look at them up really close and look for pitting.  I did do all the work myself and purchased this exact ball flex hone. I tried to buy rings for the top but they had to be custom made. Just re-used them with 42k miles on them. 

 

BUt keep in mind when doing all that work, you have to press out the cylinder liners and reseal them. I ordered the tool from a UK Lotus vendor, then I ordered the liner sealant from JaeParts.  It took me 1.5 years from start to finish. Parts sourcing, machine shop re-work of the crank and head surface, and buying tools I didnt have. 

It was a lot of work for which I was quoted $25k in California.

Thank you for the great communication your answers are helping me alot, I have bought parts in the past from JAE did you replace the other piston rings and just reuse the top? your compression numbers were really good after your rebuild.  Kent

[v8GTmac1]

6 hours ago, 99ESPRIT said:

Thank you for the great communication your answers are helping me alot, I have bought parts in the past from JAE did you replace the other piston rings and just reuse the top? your compression numbers were really good after your rebuild.  Kent

I only tried to order the top ring from Total Seal but the sales person was unmotivating when I mentioned Lotus. 

I kept all the same rings and never removed them. 

If you engine technically still runs and idles normal then A simple compression check should put you at ease. 

[Joey4420]

Well I have an update to my engine.  Everything but the physical heads and block being replaced.  Valves, cam, crank, rods, pistons/sleeves, and everything in between.  The big news is one head has already been installed so soon I hope I should hear a running engine.

 

 

[alanlambert]

Looking good,

Do you have all the parts to complete the re assembly now ?

[Joey4420]

All the parts are in stock and hopefully it will be done in the next few weeks.  The shop I use doesn't dedicate time to the engine building, so he does my engine when nothing major is in the main shop, it is a Lotus dealership though and he has built several Esprit V8's so I trust his work.

[andyblackman777]

Im currently have an engine stripped down and am in the process of measuring and inspecting all the parts to see what is good or not. 

All the main components appear to be good on visual inspection.   

I've just measured the liner bores and one of the pistons. The liners are B spec and all measure around the larger tolerance of 83.03mm on the thrust axis and around the lower tolerance of 83.15mm on the other axis. The one piston however is on the smaller side 82.975mm minimum 82.990 from the service notes.

With the largest recorded dimension of 83.04. this gives a Piston to Bore clearance of around 0.065mm or 2.5 though. This would seem just right to me but if you do the math on the service notes figures, the Piston to Bore clearance would be 0.5 to 1 though which sounds tight. what are peoples thoughts on this ? 

I see Micheal rebuilt his with the old pistons liners and rings. is that still going strong now??

Cheers Andy