Engine Assembly Problems! |
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Engine Assembly Problems! |
TeamAxisRacing |
Jan 6 2006, 08:35 PM
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#1
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Member Group: Members Posts: 107 Joined: 13-September 03 From: seattle, Wa Member No.: 1,153 |
hello i was wondering if some of you engine builder guru's have some ideas what can be wrong with my 1.7liter W code motor i tryed calling brad roberts and jake raby but both didnt answer (IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif)
so heres the dealio.. the case is together. cam is lined up correctly and the crank bearing pins are lined up (far as i can tell i did it 5 times!) everything was going fine and i was starting to torque the case half bolts and checking the rotating assembly. now there is a point in the rotation where it binds (IMG:http://www.914world.com/bbs2/html/emoticons/screwy.gif) flip it back around about 650-700 degrees and it hits the same spot. sitting there with a flash light i couldnt see any of the conrods or counterwights hitting the case or cam. so i undid all the bolts and nuts to see if it was just the case being tweeked but its not. now there is quite a bit of endplay since i dont have a flywheel on the assembly but i really dont think that will cause this problem with the rotating mass. so any suggestions? im going back out too the shop to play with it tommarow thanks... (IMG:http://www.914world.com/bbs2/html/emoticons/popcorn[1].gif) (IMG:http://www.914world.com/bbs2/html/emoticons/headbang.gif) |
dmenche914 |
Jan 6 2006, 11:17 PM
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#2
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Senior Member Group: Members Posts: 1,212 Joined: 27-February 03 From: California Member No.: 366 |
Since you state the jamming happens at about every two revolutions (720 degrees) suspect the jam is in the valve train, oil pump, or distributor drive. the cam turns at half the rate of the crank, so two crank revolutions mean one cam revolution hence one valve train cycle. Driven by the cam is the oil pump, same thing, two revs on the crank give one rev on the oil pump.
The dizzy is driven off the crank, but the gear ratio is also two to one, two crank revs to spin the distributor once. So my bet is cam gear, oil pump, valve train or distributor drive. could be bad part, junk in the way or what ever. good luck |
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