MDCmotorsports said:
Im betting #2 and #3 are both from poor deck preparation on the head and or the block or both.
If the surface isnt' smooth enough, nothing will hold for any amount of time.
the first was cause my fuel pump was failing, i replaced the head gasket and did the entire fuel system...except for the pump....which was actually the problem. detonated on it again and a few hundred miles later that head gasket blew.
this last one im betting is due to a poor surface on the block. oh well.
LuvMySilverSupra said:
damn that sucks? did it blow right away?
well this motor came from a friends car, it ran fine in his for a few hundred miles. dropped it in my car and after a few hundred miles i developed a slight miss at idle while hot.
after maybe 40 or 50 miles on the highway the overflow would fill up, i replaced the radiator cap and that seemed to work...
except the miss got worse to the point where it was everytime that cylinder fired it would miss. also, while the motor was cold it ran fine, no problems what so ever, only while hot it would do this.
i did a pressure test on the cooling system and i had an invisible leak, after letting that sit for a while i started it up and had some white smoke, leaving white deposits in the down pipe. after driving around for a while it still had the miss, but there was no more smoke.
after it filled the over flow again i could feel the gasses coming out of the line going to the overflow. at that point i parked it and started taking it apart.
this was a veryy small leak. after driving it around any deposits in whichever cylinder it was were covered over by carbon so i couldnt tell which one was leaking. the MHG looks fine and is probably reusable, though i probably wont. itll be sold most likely.
the guy who built this motor rushed the job, when my friend got his car back from him he had only filled the car with water, the timing belt jumped (how often does that happen on a 7m? not often i dont think, the first time i had ever done a timing belt was on this car, and i had no problems with my work.) when i was taking the head off i found two head bolt washers sitting loose in the head (yikes).
though, the bottom end is good, oil pressure is right and the car ran smooth. i did 13.7 at 10 pounds of boost with this motor, with the blown headgasket so it had good power.
i have another motor with a BHG, the bottom end should be fine on that one too. ill probably have the other one repaired by someone else and ill sell this block and head cheap.
