So I got the numbers back and I'm not sure if they're entirely accurate but if they are they are excellent. However, I do think they may be on the high side. The motor is from a 2010 Cooper s with 36K on it. Compression 1 - 4 205 210 205 205 Leak down 2% 3% 1% 0% I have decided to purchase it and will see if I can duplicate the numbers when I get it.
The only special set of tools you need to take on this job yourself is patience, brain, tools and a set of these.
Compression test equipment can vary quite a bit. My hose ID is very large, so the readings I get are very low, i.e., the tuners readings were 160 - 165 while mine came in at 110 - 115. I watched them do the test! It's conceivable that your 205 - 210 readings are from a hose with an abnormally small ID. If you trust the source of these numbers, put your faith in the variation. If the numbers are from the seller, try to duplicate BEFORE you commit. I'm from the QA / QC world and don't trust anybody! Swapping engines isn't a lot of fun either, but it should be a whole lot easier than repairing the original. Best of luck.
Thanks for the feedback, I went ahead and ordered it given that it comes with a 30 day warranty, so if I cant duplicate or get close to the listed compression #s I have the option to send it back. I'll test it before I put it in of course. I plan on pulling the existing motor this weekend and getting everything ready for the install. I have not received my Bentley manual yet and was wondering if you can tell me if I have to remove the whole drive shaft or if there is room to pull them from the case without taking everything apart?
I can't imagine doing a compression or leak-down test without having the engine installed. You must have access to some pretty good equipment. Getting the engine out requires removing the entire front end of the chassis --- described in the Bentley manual and probably elsewhere in this forum. I strongly suggest --- don't start until you read applicable sections of the manual. By disconnecting the disc ass'y from the tie bar and linkage, the whole thing including axles can be swung away from the transmission, suspended by the shocks. This however, leads to another special tool --- axel seals are extremely tuff to replace without both a removal and installation tool --- separate tools. You might be able to get away without replacing these seals, but I don't recommend it. And, if you have a manual xmission, replacement fluid is difficult to find, other than a Mini dealer. Maybe browse the forum for substitute fluid others have used. This would be a good time to upgrade the front suspension, shocks, springs, etc., if that's in the ultimate plan. Altho replacing shocks is also another "special tool". Some tool stores carry it, but not all. I'll explain if asked. Some of these special tools are available from a couple of our forum vendors. Don't forget to check with them if you can't find them locally.
Thanks OBW. I just received my Bentley manual today, I wasn't expecting it until Monday. I was thinking of strapping down the motor and rigging up a switch to crank it over. I don't see it as being that big of a deal as long as the motor is well restrained. I looked at the special tool for installing the seals and I am pretty sure I can make one at work. All ill need is the seal diameter and I can turn up a version of it from aluminum. No need for tool steel for something that I'll barely use. I have the auto transmission so not a problem getting the fluid, biggest pain is draining the tranny but it has to be done. I don't plan on changing the shocks at this time but that will be a cakewalk compared to this project.
Had to go out of town for a couple of days and just got back into it. Have everything ready to pull the motor except the drivers side half shaft. I have pried pulled and swore at it but it just does not want to come out. Anyone got any ideas?
@celticfc, This video is for the R53 but it might help. They remove the passenger side axle and the mechanic mentions the drivers side particulars toward the end. Cheers https://www.youtube.com/watch?v=ShWfNl35xDQ&feature=youtu.be
I finally got everything back together this past weekend. Engine runs good, only has 36k on it. I installed the latest and greatest chain tensioner that I had bought for the original. I gave up trying to pry/pull the driver's side shaft out and decided to split the shaft at the inner joint. Took all of 2 minutes to take the clamp off and pull the shaft out. This enabled me to pull the engine. I then used the slide hammer with the cv joint puller attachment to get the inner joint out. I had to ensure that I was dead square on it ,which was, I believe that biggest issue trying to do it with the engine in place. There is enough play on the shaft that it can lock when you are trying to pry it out from one side. So if anyone else runs into this issue I would recommend splitting the shaft unless of course you are not planning on pulling the engine out. I would say that there were a lot of lessons learned on this project and if I ever have to do it again it will take me half the time. So if anyone is looking for a motor to re-build or parts I have pretty much everything you would need. I'll put an ad up in the classifieds soon. Thanks to all who replied, your help was greatly appreciated.