The worlds unluckiest Elan M100

[kevrob]

A short story well really a bloody long one..

Bought the Steel Grey 89 M100 SE about 2 years ago with a known bad MAP
Crazily drove the car home probably a hundred miles with a few breakdowns on the way!
So replaced the MAP with generic cheap part (maybe not the best of ideas as we shall see later)

Car running - went out the next day to start her fuel pump failed (new relays, filter, pump)

Car running again for about 2 weeks -
Starts running on 2 cylinders hmm
New coil packs, fuel regulator - no its a failed injector
New injectors

Car running again for a couple of weeks -
Starts misbehaving wont rev past 3000rpm
Lots more work checking and I need a new magnetic pulse sensor
unfortunately not available without buying the complete CAS assembly.

So new CAS assembly car running well!

Take it out for a spin and put it through its paces then - cuts out - try to start no compression!


Hmm whats happened here then maybe belt has slipped a tooth -
After recovery - check belt its fine but compression down on No. 4
Hmmm maybe valve spring failure
Pull manifolds and head - no. 4 piston has a piece missing



So now this is serious middle of winter and im under the car -

Ok so a few tips - undo all the bolts on the t piece under the car but leave one in on a rear corner
you can then swivel the t piece out of the way - sump is pain as glued on with some super sealant
more expensive than gold - when putting back on get a sump gasket from an isuzu impulse ( also head gasket got one from an isuzu for £25)
The gearbox/clutch inspection cover is cleverly designed to also interfere with the sump!
Cut the thing with tin snips to avoid this scenario in the future.

Time to balance the bottom end - omega pistons with competition rings and then balanced the connecting rods
7gram difference between the heaviest and lightest rod thats huge!

Manifold and head castings appalling - holes more square than round the worst offender being the exhaust side of the head.
Everything corrected and radialised
After some fettling


Exhaust ports reworked:



Exhaust manifold with a propriety of heat shields only just comes out and you will scrape paint under the hood!
Heat shields and large bits of cast iron chopped away in favour of exhaust wrap, exhaust bolts replaced with stainless steel.

Turbo inlet side rebuilt with new bearing and billet wheel.

Exhaust side heat hell has taken its toll I couldnt get the bolts out would of had to cut them so left for now.
That huge cast iron collector must way a ton have no idea about the technical reason of why its needed but guessing it produces a lot of back pressure.

Cambelt cover what a pain in the arse!
I managed to remove it in situ without undoing the engine mount..
Not sure how now but its a swine and then you have to wrench the top cover out-
Well its not going back now but if it did ive sawn off the mounting inside the cover for that annoying bolt and to
Make the cover fit easier.

[kevrob]

Part 2 cutting a log story short..

All the hard work seems to of paid off lots of other improvements made on the way..
Car now runs well all the way from low rpm with still no lag, adjustable manual boost controller appears
now redundant as im making a lot more boost..
Will do some log-runs soon ..

[Tuga2112]

ive only very at a glance read your messages but seems like you need help, and theres a pretty good chance you would have had it all in this forum

the first thing i noticed was the "MAF " mention.
i know im being pedantic here, but terminology does make your google searches a lot more efficient.
the M100 doesnt have a MAF> it has a MAP which although they have similar effect (give the ECU an idea of how much air is avaiable to mix with the fuel. they do operate differently. one reads pressure, and other reads flow.

"Lots more work checking and I need a new magnetic pulse sensor
unfortunately not available without buying the complete CAS assembly."

now thats strange, as SJ (which is the easiest point of call, but not necessarily the supplier with the best reputation) does sell only the sensor to make the refurbishment.
i never looked into it but i would assume its also just a general purpose part that you can buy from farnells. im sure peter, geoff or jonathan will correct me if my assumption is wrong.

Pull manifolds and head - no. 4 piston has a piece missing

thats very unfortunate, i sympathise.

Car now runs well all the way from low rpm with still no lag, adjustable manual boost controller appears
now redundant as im making a lot more boost..

generally speaking. the advise is to remove that ASAP as they can go wrong, and cause some serious troubles with making the car run lean.
RonR can supply everert chips. which is the established default of performance upgrades safely without needing to be a wisard.

[kevrob]

Thanks for the info if I can get hold of an Everest or Mountain chip that would be ideal now.

[kevrob]

Of course I meant MAP comes from rebuilding Porsche 944 at the same time..plus an E30 BMW and an XJ12 gets confusing!

[RonR]

( also head gasket got one from an isuzu for £25)

Hi Kevin,

Do you know the provenance of your £25 head gasket?
If it's meant for a non-Turbocharged car or from a manufacturer of "Pattern" parts it may fit but there are differences, most obviously in the coolant holes, it's why there are 2 different part numbers for the N/A and Turbo cars. You'll see threads on here where a new non-Lotus gasket has failed after a short time.

The LEC accepted wisdom is to use the "Pattern" sets for all the other gaskets and then shell out for the proper Lotus/Isuzu head gasket, especially if you want to run higher levels of boost.