MG Montego 2.0i Engine Swap

[Ed]

Hi Guys

This weekend I am putting a 59K engine out of a rotten 1991 MG Montego 2.0i into my 1988 MG Montego 2.0i mainly because the old engine uses more oil than petrol, and the 1991 engine is hardly run in!

Will I encounter problems with the engine management system and multi-plugs? The F reg car has the black box under the bonnet and one above the glovebox, and the 1991 car has just the silver box under the bonnet.

Any advice to help my poorly MG would be most appreciated.

Cheers

[MGTurbo]

Hi Guys

This weekend I am putting a 59K engine out of a rotten 1991 MG Montego 2.0i into my 1988 MG Montego 2.0i mainly because the old engine uses more oil than petrol, and the 1991 engine is hardly run in!

Will I encounter problems with the engine management system and multi-plugs? The F reg car has the black box under the bonnet and one above the glovebox, and the 1991 car has just the silver box under the bonnet.

Any advice to help my poorly MG would be most appreciated.

Cheers

The actual engine itself is no different, although the sump and breather system is, you may want to keep the later set up because its alot better.

The Lucas system will work as per the early MEMS type if you retain the 88 loom and fit it onto the 91 engine, if this makes sense. The inlet manifold had some slight changes (mainly the stepper motor, which bolts on anyway) so you could fit the 88 manifold onto the 91 engine to keep it simple. You have PM BTW.

Gareth

[Ed]

I am taking the whole engine out of the 1991 first, detaching it at the downpipe/manifold joint. Will be keeping everything on the 1991 engine like starter motor, alternator etc so I really only want to have to use the old 1988 loom to plug into the 1991 loom. Will it just be as easy as that or am i dreaming? :laugh:

[MGTurbo]

I am taking the whole engine out of the 1991 first, detaching it at the downpipe/manifold joint. Will be keeping everything on the 1991 engine like starter motor, alternator etc so I really only want to have to use the old 1988 loom to plug into the 1991 loom. Will it just be as easy as that or am i dreaming? :laugh:


Yeah, pretty much except the stepper motor area that i already mentioned. Use the 88 engine loom otherwise it will be more complex and you'll have to use the MEMS Ecu.

Gareth

[Ed]

MEMS, is that the silver ecu?

[MGTurbo]

MEMS, is that the silver ecu?

Yep, Ignition and fuelling combined whereas the early one is two seperate ECU's.
Gareth

[Ed]

ok, i am confused. My F reg Monty has the black box under the bonnet which i thought meant there would be another in the glove box but there isn't!? I thought only the silver type worked on its own?

[MG Stew]

Dont know if mems (silver ECU) is the same on montys, but on a metro you have to have a matching alarm box (usually a black or silver box in the glove box) for it to work. Hope this helps..

[MGTurbo]

ok, i am confused. My F reg Monty has the black box under the bonnet which i thought meant there would be another in the glove box but there isn't!? I thought only the silver type worked on its own?

It's not in or above the glove box, its in that area behind the carpet on the bulkhead...

Gareth

[Ed]

Arh, I'm with you. Yeah its got one of those. Mystery solved, hehe :laugh:

[MGTurbo]

Arh, I'm with you. Yeah its got one of those. Mystery solved, hehe :laugh:

;)

[Blair G]

Your best bet is to change the whole wiring loom over as trying to connect an engine harness to an existing loom is more touble than its worth. Changing the complete loom over is a lot easier than you think and it prevents problems at a later stage.

If however, the both cars are running MEMS (or Lucas) then do a staight for straight swap as the connecting plugs will be the same.