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MC's M96.01 strip down and rebuild

MisterCorn

Well-known member
Joined
8 Jan 2011
Messages
9,410
This is where it starts.......



I bought a spare engine for my C2 some time ago. It has a reported light knock in the bottom end. As I like a tinker my plan is to strip it and rebuild it. At the moment it is just about to go on the engine stand to get started.

I will strip and inspect the engine, checking the crankshaft, pistons and bores. If there is any scoring or bore ovality I will probably go for a 3.7l conversion to futureproof the engine.

As this is an early engine it has the dual row IMS bearing. I will look at options for that. Favourite for me would be the latest larger bearing since the engine will be apart, but will worry about that when I get to it.

I will look at getting the valve seats recut as I have read it is beneficial, and then rebuild the heads with new seals. Then new guides/chains/bearings/core plugs after getting the crankcase and heads cleaned.

I have got myself a spare room at the office to work in so I have plenty of space and light. I am in no rush as the engine in my car is absolutley fine, bar a couple of tiny oil leaks.

Given the symptoms I expect I will be looking for a good secondhand crank, so that will be the first £1k gone. But not commiting to buying anything until it is stripped. I will document the work here including costings for any other enthusiast who like to wave a spanner in anger.

When built my plan would be to swap it in to my C2 and then probably rebuild that engine as a spare. It is currently on 60k. Otherwise I would sell the original as a good running engine before removing it.

Wish me luck.....

MC
 
Looking forward to this MC.

Fascinating stuff. Doubt I'll ever undertake it although I'd like to.

Good luck. :thumb:
 
Good luck! I see you have some light refreshments in the rack there to keep you going as you work :thumb:
 
asterix_the_gaul said:
Good luck! I see you have some light refreshments in the rack there to keep you going as you work :thumb:


This is in my store room, not where I will be working. Too much junk!!
I'll put up photos of the work room when it is in there. Hopefully tomorrow morning.

MC
 
The engine was lifted on to the stand using webbing and an engine crane.



The engine is fixed on three points on the crankcase which has the water pump and one point on the other crankcase, with the centre of the mount as close to the crankshaft centreline as possible to centralise the mass. When it comes to splitting the crankcases it will be held on the three mounts on one half, by then there will be a lot less weight on it.

Bolts used are M12x1.5mm 100mm. Note that this is a fine pitch M12, not the standard thread. One fixing uses 10mm studding.



Once mounted I turned the engine upside down to drain more oil and water on to the drip tray. I have read before about how much comes out of these. I might move to the tiled garage for initial disassembly to make sure I don't ruin the carpet.

Initial inspection of the exhaust ports show that one looks oilier than the others.





I'm not sure if that is relevant to the reported issue, but something to keep an eye on.

This is where I will be doing the dissasembly of cleanish parts and the assembly work.



There is a decent amount of storage in the drawers and shelved, I just need to have a bit of a tidy up first.

I won't be getting anything done over the next 10 days as I'm out of the office, but I will be reading a lot about options for the engine and how to do jobs on it.

First job will be to remove the sump and oil filter not gbecause they need to come of first, just because I want to see if there is anything interesting inside them. Then get the camshaft locking tool in and remove one of the heads. I picked up a set of M96 timing tools from eBay for £99. I'll be reporting along the way on whether or not they are any good.



Engine number appears to be M96/0166X09394 which dates this to a 1999 unit, so it is one of the later ones of the /01. Not that I think that makes any difference, I don't know of any changes during the life of the engine.

MC
 
MC the start of another must follow thread :thumb: good luck with the rebuild this will be interesting to know what you find as you strip it down,

:popcorn: :popcorn: :popcorn: :stay:
 
Me too!

 
Good luck with this MC

I will be interested to see the following:

Bore ovality measurements
If it has ferrous coated Pistons (I suspect not)
Condition of the cam chain guides in the heads
Condition of ims/crank chain guide
Condition of main crank bearings
Slop in little end bushes



:thumb:
 
I thought I had a problem with parts hoarding - but a spare engine!?

Cracking, I would be tempted to do this too.

Makes sense if you do it yourself over a long period of time - when you have finished, so long as your current engine runs well you will might well be able to sell it for what the rebuilt / upgraded engine cost you in parts.
 
MC :worship: What a project! Like as others have said I am looking forward to the updates
 
wasz said:
I thought I had a problem with parts hoarding - but a spare engine!?

Cracking, I would be tempted to do this too.

Makes sense if you do it yourself over a long period of time - when you have finished, so long as your current engine runs well you will might well be able to sell it for what the rebuilt / upgraded engine cost you in parts.

Just because I have a worse problem than you doesn't mean you don't have a problem.
All I know about the engine is this from the advert:


'996 3.4 ltr engine 118 k miles 
prior to replacement unit was running after top end refurb as low compression on 5 and 6.( possible valves burnt incorrect diagnosis) new stem seals springs tappets and valves lapped, heads leak tested and max compression achieved. after refit problem diagnosed as big end shells. engine was run for less than 5 mins on ramp but knock on one piston audible. 50 50 chance that crank is undamaged as not driven or over revved and could just replace shells but not guaranteed. '

No plugs in the engine.
This would explain the dirty exhaust port.

MC
 
Demort said:
Aww excellent another repair post :popcorn:


Btw .. move it off that carpet .. please .. i know how messy this is going to get :D

I will be doing. Very happy to have you on board. I might need some guidance....

MC
 

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