3 replies to this topic

[Zeemax Adventure]

My Mini Cooper sport came in bits, including the engine to an extent. This is the first time I'm going to attempt an engine rebuild so looking for as much advice as I can. Also any mods relevant for a few more horsies
Thanks

[Cooperman]

The first step is to clean everything then measure and record what you have at present.

Measure the bore diameter to see if it has previously been re-bored then check the pistons to see what the part number is and whether they are an oversize. Any oversize is marked on the top of the pistons. Check for a small step at the top of the bores which indicates a re-bore is essential. In fact, it is advisable to assume a re-bore with new pistons will be necessary.

Inspect and measure the crankshaft journals, the thrust bearing faces and the flywheel mounting taper. Have the journals been reground to a smaller size? If so by how much? Are the journal surfaces smooth or are they slightly uneven and thus need a re-grind.

Inspect the camshaft lobes with a magnifying glass for signs of damage to the case-hardening of the surface.

Clean and inspect the valves themselves and see how much play there is in the valve guides with the valves in them but without the valve springs.

Strip the cylinder head and measure the valve sizes. Inspect the valve seats and check the rocker shaft for wear on the bushes and/or the tips of the rockers.

Really have a good look at everything.

 

To do this you will need a 1" to 2" micrometer screw gauge and a digital vernier caliper.

 

Once you have done this, come back on here with the results and we can then mover on to the next stage.

It is very rewarding to re-build your own engine and it is not that difficult, especially with the help you will get on here.

Don't be afraid to ask anything on here, we are all here to help.

Good luck with the project.

[Zeemax Adventure]

Thanks cooperman, that's really helpful. Not sure when I'm going to get round to doing it as I have so much on at present but will keep this for reference

[Guess-Works.com]

Being an MPi, and I assume it's going into an MPi with the Rover MEMS ecu, then there's not too much you can do performance upgrade wise...

 

Of the std injection engines I've built the SW5i is a good cam upgrade, and coupled with reasonably worked head will give good bang for your buck...