1991 Lotus Esprit - 20 (Engine - Liners are removed)

After a little over a year at the machine shop, I decided to take matters into my own hands regarding this engine rebuild.
#lotus #lotusesprit #rebuild #esprit #project #reclamation

[@boogerhead0]

In pulling liners, I have always used a length of stainless tubing, ID larger than OD of liner, a plate turned on a lathe, having a sufficient lip (toe), not unlike a blind bearing puller, the bottom, lipped plate having a hole through center (edge-milled as necessary for the crank web clearance), and a top slab with hole through center, which will span and center on the tubing. This entire apparatus is a standard cylinder liner puller, very familiar to those who have done tractor engine repair, and/or ATV jug repair. The stainless tube must be long enough for the pulling liner to enter, and clear. The tube rests on the head surface, and so must clear any studs protruding, or remove those studs. I have lucked out getting various stainless tubing diameters from aircraft supply houses. All-thread goes through the top plate and bottom, toe plate, nuts on both ends. A pair of wrenches pulls the lower toe plate on the liner edge, and the liner slides up into the tubing as the nuts are driven. Beware some engine builders have applied permanent thread locker, so heat may be required to break that bond.
On occasion, I have placed the block with liner puller installed, into an oven, in hopes of slightly expanding the block over the liner.

[@BillyWillicker]

QED Motorsport lists cylinder parts. Your bottom end repairs can be done two ways. One is the right way with new liners and piston kits. The other is to clean it all up(spotless) and use a sleeve retaining compound or sealing agent to reinstall your original liners and pistons - this would only be an option if the bores are within acceptable sizes, both in the block and the liners, AND the piston skirts are good with acceptable cylinder to bore clearance.
The bores in the block are likely not round nor the same size as they were when it was new. Time, heat cycles, and stresses have seasoned the casting. Castings are machined when they are new, or "green" as it's called. As they age and are heat cycled and stressed the metal moves around and machined features will change shape and size.
Using an interference fit as a fluid seal alone is not done any more due to the nature of castings and the troubles of aging.

[@Rick_D]

Hopefully this machine shop has the skill to determine if the sleeves can go back in and hold up. I’m guessing this engine, with only 31K miles on it, has been apart before given the sleeves had crude engravings on the outside to number them. If the sleeves were removed before, maybe it’s possible this is the 2nd time this has happened. I really need this shop to give me an accurate assessment on this block and sleeves in order for me to sleep better at night

[@BillyWillicker]

@@Rick_D The engravings are likely factory markings. Checking that will be very straight-forward. I could do it as I have the tools but I don't think I'm close. Standard piston clearance checking tools(micrometers and dial bore gauges) are all that's needed and any machine shop worth a rip will have many.

[@Rick_D]

@@BillyWillicker "The engravings are likely factory markings"...that would be great if that were the case but why would Lotus free hand scratch a 1, 2, 3, 4 on the liners on a new engine? When those sleeves are new, why label them?

[@BillyWillicker]

@@Rick_D Fitment. Bore clearance to each numbered piston. A many number of reasons. No two holes are identical, no two cylinders are identical, no two pistons are identical - especially in 35yr old production parts. Those cars were hand built and factory blueprinted. The assemblers kept notes, many times on the parts themselves. Very common.

[@tomthompson7400]

good grief ,,, watching that liner go from side to side was painful ,,,

[@Rick_D]

They’re at a new machine shop now so hopefully I’ll know condition soon.