5 replies to this topic

[Lenhamracer]

Dear Mini friends

 

I have a problem with my cooper s engine. I took the engine out to swap the diff for a quaife and thought it might be good to have a look into the cylinders as I noticed a drop in the compression.

There are an lot of scratches and there are not many honing traces left. Also I found a lot of hard baked carbon.

It is time for a rebore but I a in a historic regularity rally in two weeks. 

Do you think it is worth to rehone it with a drill and a honing adapter from amazon??

Unfortunately I don´t have enough time to rebore the engine and it ran like that at the last event and I thought a bit of honing is better than nothing...

 

Thank you and kind regards

 

Thomas

 

[Spider]

In short - no. I did a bit of a write up on this a while back;-

 

http://www.theminifo...gine-machining/

 

[Lenhamracer]

Thank you for your comment. I forgot to attach the picture..

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[bpirie1000]

How much did the compression drop of late?

Might be a tell tale sign that things need to be 'Attended to

Depends how hard you drive it on the regularity rally.

[Lenhamracer]

Sorry for the late answer...

Rally done and it was big fun! Engine was fine, I even managed to be 24th of 90 entrants in the steering wheel trophy (driving on closed tracks)! Today I started taking the engine out again. I found a lot of shaving on the draining plug magnet. Will attach a picture, any idea where they could be from? I will have a close look into the gearbox...

 

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[Spider]

Great result !

 

The 'fur' on the sump plug to me looks normal, it's largely from normal wear of the baulk rings.