15 replies to this topic

[richw911]

Can some one list what need to be changed when putting a metro engine into a Mini

1 Thermostat housing?

2 bell housing cover?

3 ?

[Tommyboy12]

Thermostat housing is a preference. Mine is still the Metro item.

I dont think you need to change the bell housing either. Its the clutch arm that needs changing.

Engine mounts are a must. It wont fit without the Mini items!

[richw911]

Mini Fan for rad

[Ethel]

You'd also have to ensure there's some sort cooling bypass.

1. Left hand engine mounting adapters: 12A360 & 12A 361.
2. Engine steadies
3. Speedo drive pinion (if you want an accurate speedo)
4. Cooling system (matching bypass & heater take off)
5. Clutch & starter (only if you're converting from pre-verto to Verto or vice-versa.)

I think the cable clutch arm is the same as on the hydraulic verto?

[firefox]

Electronic ignition dizzy 65DM4 so wiring needs to be changed, integral starter, remove inner wing solenoid, and again change wiring

check clutch metro may be Verto, and my engine mounts fitted but may have been in a mini before i bought it

Edited by firefox, 14 November 2012 - 03:28 PM.

[richw911]

Thanks everyone

[smartie93]

You'd also have to ensure there's some sort cooling bypass.

1. Left hand engine mounting adapters: 12A360 & 12A 361.
2. Engine steadies
3. Speedo drive pinion (if you want an accurate speedo)
4. Cooling system (matching bypass & heater take off)
5. Clutch & starter (only if you're converting from pre-verto to Verto or vice-versa.)

I think the cable clutch arm is the same as on the hydraulic verto?

Why does the mini need a bypass hose and the metro doesn't? I've run two metro engines without bypass hoses with no problems, and ones a slightly "hot" MG

[tiger99]

I did this once, and did not fit a bypass hose. There was no problem with the cooling system.

But, the gear ratio was completely wrong. I can not be certain that the engine assembly was from a Metro, as it could have been from an Allegro, whatever its source it was a ridiculously high ratio for a City E, which accelerated almost like a dragster, but only up to about 50 mph. Clearly it had come from a car with large wheels.

Having done the engine swap one weekend, I could not be bothered to take it all out again, and remembered that in the 1960s, rally teams routinely changed final drive ratios in situ, so I did it that way. But it is far easier to do it before fitting the engine to the car! No need to split the engine and box, it is all done by removing the diff casing and the end housing where the speedo drive is.

Edited by tiger99, 15 November 2012 - 09:47 AM.

[SolarB]

Why does the mini need a bypass hose and the metro doesn't? I've run two metro engines without bypass hoses with no problems, and ones a slightly "hot" MG

Metros have a different hose layout but they do have a bypass system.

Water flow through the A series engine is in the order of: pump - block - head - thermostat - top hose - radiator - bottom hose - pump. However, this only happens when the thermostat is opened. When the thermostat is closed the water circulates within the block and head (and heater if required) but flow around the head at the thermostat end is restricted. This restricted flow can lead to hot spots, head gasket problems and perhaps head warping if you’re unlucky.

The small bypass hose on Mini engines allows the pump to suck water down the hose from the head and return it to the block when the thermostat is closed, restoring proper flow. Metros did away with the bypass hose, instead fitting a sandwich plate under the thermostat and it’s housing. With a Metro setup a hose connects the sandwich plate to the lower radiator hose (through the intake manifold if I remember correctly) and this allows correct water flow before the stat opens, performing the same function as the Mini bypass hose.

If you run neither it’s recommended to drill a couple of small holes in the thermostat to allow some water to flow through the top hose before the 'stat opens. Having said that, the two 'stats I've been playing with recently both flow a reasonable amount of water when cold and fitted to the head. If in doubt, disconnect the top hose on a cold engine and start it up. If water flows you're OK without the additional holes.

[smartie93]

Why does the mini need a bypass hose and the metro doesn't? I've run two metro engines without bypass hoses with no problems, and ones a slightly "hot" MG

Metros have a different hose layout but they do have a bypass system.

Water flow through the A series engine is in the order of: pump - block - head - thermostat - top hose - radiator - bottom hose - pump. However, this only happens when the thermostat is opened. When the thermostat is closed the water circulates within the block and head (and heater if required) but flow around the head at the thermostat end is restricted. This restricted flow can lead to hot spots, head gasket problems and perhaps head warping if you’re unlucky.

The small bypass hose on Mini engines allows the pump to suck water down the hose from the head and return it to the block when the thermostat is closed, restoring proper flow. Metros did away with the bypass hose, instead fitting a sandwich plate under the thermostat and it’s housing. With a Metro setup a hose connects the sandwich plate to the lower radiator hose (through the intake manifold if I remember correctly) and this allows correct water flow before the stat opens, performing the same function as the Mini bypass hose.

If you run neither it’s recommended to drill a couple of small holes in the thermostat to allow some water to flow through the top hose before the 'stat opens. Having said that, the two 'stats I've been playing with recently both flow a reasonable amount of water when cold and fitted to the head. If in doubt, disconnect the top hose on a cold engine and start it up. If water flows you're OK without the additional holes.

Cheers for the info, I run the sandwich plate so that explains why I'm fine then :)

[Ethel]

Well almost, Metros also have permanent flow through the heater (temperature is controlled by directing the air instead of a water valve). If you use a sandwich plate in a Mini you could do with a bypass for the heater valve instead - like the SPI bottom hose.

[Algordo1100]

So I have a 998 A+ block with a Metro 1275 A+ head on it. I have always assumed this head is a 12g940.
The head has no bypass facility so I fitted a metro water pump. I am not using a sandwich plate under the 'stat housing. Should I be considering a different set up?
It seems fine as it is, however I have had to redo the head gasket since the head went on. could this cold flow issue have been a factor?
I never shut the heater tap, not even in summer, I just shut the flap if im hot. I like to keep a flow through the heater matrix as i think it helps it not to gunk up. Would this negate the need for a bypass?

Al

[SolarB]

Cheers for the info, I run the sandwich plate so that explains why I'm fine then :)

Did you modify the sandwich plate? I've just spent a couple of hours moving the position of the outlet pipe on the sandwich plate casting.

[Ethel]

There are several different sandwich plates Metro, Mini SPI...

If you have no bypass, you can drill a few small holes in the rim of the thermostat to let a little water flow so it senses temperature better.

[smartie93]

Cheers for the info, I run the sandwich plate so that explains why I'm fine then :)

Did you modify the sandwich plate? I've just spent a couple of hours moving the position of the outlet pipe on the sandwich plate casting.

No i didn't, but you need a mini top part as the metro has a feed for the expansion tank which of course a carb mini lacks.

My radiators mounted on the inner wing rather than the usual place so I've got custom hoses.