Hello all,

New issue on the project R53. I posted previously about having a slow cranking issue, and was able to determine that the battery and alternator are both working fine and the system has enough power. I'm getting 13V off and 14V+ on idle. Terminals are tight and grounds are all attached. No weird electrical issues in the car like when the battery is bad.

Today I went for a small 15 minute drive all was well, the car started up mostly fine (still slow cranking but not more than before). About an hour after I got back, my sister came over and wanted to go for a ride, so we went out, I press in the clutch and throw it in neutral, turn the key, and not much happens. I can hear the starter moving, but VERY slowly. I tried this a few times and on the third it turned the engine enough to get it started, but this shouldn't be happening. I went out and drove my sister around the neighborhood for a bit, then came back and shut it off. I tried to start it again to see if it was just a fluke - nope, nothing now. Not even a little movement from the starter. I didn't hear any clicking or chattering from it either.

I'm pointing at the starter now, as I can't think of anything else that would cause this issue. Does anyone have any other thoughts on this or experience dealing with an issue like this? I need to lower the subframe soon to do some other work soon so it's not a huge deal if I have to replace the starter while I'm down there too.

 

You checked terminals in the back and the front??

Did you actually pull the ground terminals on both ends and clean them?
Same with the B(+) on both ends?

Sometimes the terminals on the ends of the cables can work loose/corrode etc... had a mystery issue on another vehicle like yours.. turned out to be the cable was loose inside the factory crimped terminal..

 

I haven't pulled the ground terminals but I cleaned their connection points when installing the new engine. Battery terminals and cable ends look clean and free of corrosion, minus some surface rust on the outside (inside of connection is clean). Someone in the Mini subreddit recommended I test for a current draw. I'll give that a shot but to be honest, the starter on this car has always felt slower than it should be and I'm wondering if it was bad before I even replaced the engine. Probably should have just bought a new one when I had everything out!

 

Would get it tested at a (hopefully competent) brick and mortar parts store. Auto Bone, Crapa, Oh'Really?, Pep Girls etc Bring the battery and alternator along with it you while you're at it...

Also +1 on ground terminals and a current draw test if those all check out good.

 

Unless you remove and clean/grease and retorque the terminals... you'll not know for sure.

Includes the ones in the hatch, under the hood and at the starter 3 locations) .... both (+) and (-) terminals.

 

This was the fix for my car as well. It had been sitting for years with a no crank problem and a few hours later it was running again with this method.

 

Found the fix! It was the passenger engine mount ground strap. Apparently it had cracked at some point and slowly broke away just enough to cause an unstable connection. Rerouted that end of the ground to the SC mount where it connects to the block as someone in another recommended. No issues since!