to make a long story short, we had no compression in cylinder 1 on the mini coop s we have been rebuilding. this project was taken on as a bit of a rebuild and then sell, but with buying a home soon we will most likely sell once back together.

picked up a full engine rebuild kit with carillo 9.5:1 and all the goodies to go along with it.. but unfortunately after we buttoned up the motor it slipped time and suffered some valve to piston contact on the exhaust side. Im not sure how it happened other than suspecting that valves were sticking badly and forced the motor out of time. when we tore it back open it was way off on the exhaust side. good news is that the pistons appear to be alright with only some small gouges and indication of contact. however, the head suffered bent valves in each cylinder on the exhaust side. we have been wagering the difference in rebuilding our head, or trying to source a reman unit or a good used unit. a little nervous to eBay shop for a used cylinder head.. does anyone within the forums have one for sale? any members know the cost of rebuilding a cylinder head? any suggestions or insights would be greatly appreciated. car ran like a champ the first 15-20 miles or so and then mid way through third gear it all went to S%&T.

 

rebuilding the head is very cheap...buy the valves (interval valves or TRW) it takes few hours to do that.

rule of thumb, ALWAYS rotate the engine by hand few rotations to lubricate internals and make sure timing is good.

Also, was the vac pump inspected, it could've been dry and seized!

where are you located?

 

located in grand rapids, MI.

we rotated the engine, cam lubed everything and timing was spot on with no issues. car ran great for the first 20-30 minutes, however after a few test drives it either slipped time, a valve stuck and forced it to jump time, or who knows what happened. if the valves are bent should i be worried about the valve guides being damaged as well? ive sourced a good used head for 500 bucks shipped to me through my work, but if you're saying i can just purchase a new set of valves and swap them straight in i could handle that. would i just lapping compound them when installing and call it good? what if the seats of the head have been damaged? vacuum pump was good and spinning freely when installed as well.

 

Did you have a Bentley manual or equivalent literature with torque specs, and did you use all of the cam locking tools?

All 8 exhaust valves are about $360, and if you hadn't done the valve guide seals when you had the head off I would highly recommend them. As for valve guide damage; we haven't had much trouble with that on cars that have crashed valves, but we have had a couple of occasions that some of the exhaust seats had been damaged. If you can't undertake the head work it may run you in the neighborhood of $3-400 in labor for a machine shop to go through the head, plus parts.

These cars timing cassettes don't key or press fit the cam gears, so even when you do the job 100% by the book it may jump time just based on the design. We've had them jump marginally, but just enough to give a poor idle and cam codes, we use a Loc-Tite red on the cam gears and let the car sit for an hour if possible, but it's not a widespread problem that they jump time after being reassembled.

 

thank you for the input NKFRY. yes we have the book and did everything by the book as well. literally just as you said, red loctite and the whole nine. only thing i can think is that some of the valves were sticking, or possibly excessive oil in the thread hole of the exhaust cam. intake cam was spot on. we rolled the motor 3-4 full rotations, keyed the flywheel and recheck with all the necessary cam timing lock tools. was pretty bizarre. all i can think is that the exhaust bolt gave way (it was a new bolt) or the exhaust valves were sticking and forced it to slip time. it did however run like a top the first test drive, little bobble on the second test drive which is when most likely it was coming off timing, and then the third drive it let go completely. i see some exhaust valves online for like 15 bucks a piece on pelican parts, but im leaning towards a good used condition head complete so i dont need to break the cams from the head.

 

Pretty sure you can get all 16 valves (intake and exhaust) for $195 if you look around. This kit did not come with keepers though, so don't lose any and inspect the ones you take off to make sure they aren't chipped (I had a chipped one and I lost a couple).

 

found a good used head complete from a source through my work for 500 bucks shipped that was removed from accident vehicle with 60k. going to go with just a used cylinder head and ill take it to my local machine shop for any servicing and pressure testing. just dont have the time to piece it all together and rebuild. hoping that the used head will get this car back on the road and off to a happy new owner. gotta admit the first couple test drives i took with the vehicle before it went haywire i was impressed. never ridden in a mini before and it seemed to drive on rails. didnt get into the powerband obviously because of the break in process, but was a really cool car.