DJM3 0 Report post Posted August 8, 2022 (edited) Hi all, Was hoping to get some advise - I am elbow deep in a head gasket build on my M3 and was progressing through the cam install and timing. this where where I think I made a boo boo. on the “intake cam hub” I has everything fitted up and was aligned (2 bolts in the hub ) but they were not tight . I then proceeded to rotate the engine (by hand) and the locking bolts moved all the way to the end of the “slots” My question is- have I now made valves kiss pistons ? Or is there a margin of safety with these “slots” on the hub? sorry is that is not easy to flow ! adding a bit more content The intake hub was assembled, 2x m8 bolts were securing it ( just not enough to stop the bolts sliding all the way to the end of the “slots”) so when I hand cranked, it all moved . I added a picture - In the top picture that is the amount of “movement “ in the hub circled in blue. The bottom pic was the hub assembled- how I had it (just not tight enough) Hoping that “that amount of movement “ was within safe limits !!! Edited August 8, 2022 by DJM3 Quote Share this post Link to post Share on other sites
jon dee 500 Report post Posted August 9, 2022 Valves are tough little bastards... if a piston hit a valve on the way up while you were turning the crank by hand, it would have stopped. Or at least there would have been a point at which the resistance to turning increased noticeably. If it turned smoothly and easily (plugs out) and you didn't feel anything I think you should be fine. Cheers... Quote Share this post Link to post Share on other sites
M3AN 4016 Report post Posted August 9, 2022 As per the feedback you received over on 'Cutters, you're fine, the slots are 100% well within the safe range of motion... or they'd be shorter. Quote Share this post Link to post Share on other sites
DJM3 0 Report post Posted August 10, 2022 19 hours ago, jon dee said: Valves are tough little bastards... if a piston hit a valve on the way up while you were turning the crank by hand, it would have stopped. Or at least there would have been a point at which the resistance to turning increased noticeably. If it turned smoothly and easily (plugs out) and you didn't feel anything I think you should be fine. Cheers... Hi Jon Dee, thanks for the reply - im now second guessing my memory - I dont know if it was because it was the first time i had hand cranked the engine in about 6 month or there was some slight resistance. But it did feel "tight" for that first rotation and after i redid things it was more free. . but again i could be all in my head. 16 hours ago, M3AN said: As per the feedback you received over on 'Cutters, you're fine, the slots are 100% well within the safe range of motion... or they'd be shorter. Hi M3AN! Log time, Thanks for replying, I do feel much better hearing that now! Im just not sure why the valves are leaking air/ bubbling when i put solvent in the intake port and apply compressed air. My engine builder did say there was 2 options for this 1. I bent or damaged the valve face 2. there is rust on the valve seat as the head has been in storage for 7 months before i put it on I will be putting a scope in the bore on saturday anyway Quote Share this post Link to post Share on other sites