just finished putting a gen2 3sgte head on my gen1 3sgte bottom end in my st165 to replace the infamously cracked head, having an tough issue though. when i try an time the engine, which obviously needs to be done since the head swap. it seems to keep jumping teeth whenever i try to start it. i have tensioned the belt to what i believe to be enough, using the bgb as a guide. i can turn the engine over 2, 5, 10, even 20 times and the timing stays spot on, but when i actually try to start. it either won't start, or will run and then the timing will be off by as much as 60 degrees on the cam. i have no idea what could be going on and i don't have the resources to pull the motor and watch it. a few details about the head swap. new oem gen2 tensioner and tenstioner pulley, stock cam gears on gen2 3sgte cams, gen1 timing belt and entire bottom end (water/oil pump, block, pistons blah blah) please help this has me tearing my hair out.
Which cam is slipping? The gen2 gte uses a gen3 style tensioner, sounds like it's not locking down? Cam timing/shimming notes - http://st162.net/forums/viewtopic.php?f=101&t=6934&p=109810#p109810 My guess is the belt is loose, the intake cam is slipping and putting the distributor out of wack? Did you find a gen2 bgb for the tensioner workings or trying the gen1?
Hey Kevin........... I'm a curious critter and far from a mechanic but I was pondering while looking at my BGB. The intake cam has way more belt teeth on it compared to the exhaust cam................ is the exhaust cam slipping and maybe the belt needs to be a tad tighter............. or do I need to take a crash course in motor mechanics :shock :lachtot :cheers
uhhhh. i am pretty sure the cam gears are NOT different diameter's or have different number of teeth, that would cause the exhaust cam to change orientation each revolution (e.g. first rotation, everything fine, second rotation, 2 teeth off, third, 4 teeth, etc.) either way, i'm using the st165 cam gears, could this be causing the problem? i would think not because the number of teeth would then be the same. i'm thinking that when i took the belt off, some slack may have developed under the lower timing cover and i just can't see it. or maybe my tensioner is too loose?
The cam pulleys are the same size (cams always turn at 1/2 crank speed) Only time this happens is when guys put a GE head on an FE block and forget to swap the crank pulley (GE/FE pulleys are different sizes) Either the belt is not tight or like you say there's slack somewhere. That is why I wrote the article. I've added in a simple cambelt HOW-TO as well http://st162.net/forums/viewtopic.php?f=101&t=6934&p=109810#p109810
i also deleted all the water/vacuum lines from the back of the intake manifold (vac to power steering, coolant to isc, a/c idle up, etc.). would this have anything to do with it not starting? i doubt it but might as well ask because someone is actually responding here (unlike alltrac.net). also, the vsv on the back of the intake manifold with the yellow plug is the fuel pressure up vsv or something. two vacuum hoses, one going to fpr, other to intake manifold? Edit: just thought of something else, tvis is disconnected, this wouldn't have anything to do with it, or very little, right?
I know that cam gears are the same size and knowing me I probably didn't explain myself properly due to the fact that I'm pretty much an amatuer with mechanics but I do try to understand :banghead So, what I think I was trying to say was that the Exhaust cam has LESS belt teeth on it while spinning compared to the intake cam and if the belt is loose enough it's more likely to jump a tooth on the exhaust cam............... I really have no idea but that's just how it registers in my head........... Am I talking shit and got it totally wrong ?, let me know............ I'm just trying to understand it :cheers like you say and why I love this site above all others is the lads respond quickly and nothing is left unslolved :thumbsup:
Yes :lol2 You can swap cam pulleys over I can't see any of that making it not start. I fail to see the point of deleting it all - eg. without the ISC heat it won't idle properly, I know that deleting the vacumm also does weird shit to the trottle body. The trick to motors is to do one thing at a time, ie put it back to stock, get the timing right, then start it up and run it and then delete the stuff you want to delete one at a time. That way you will know where you went wrong and not a trainsmash like it is now
spiderman i understand what you mean by the "less teeth on it". like only 90* of the exhaust gear has belt on it at any one time whereas the intake cam has 180* of belt on it. stig, i took off the lines back there simply because i couldn't reattach them once i had bolted the intake manifold on, and i couldn't bolt the intake manifold on properly with those lines on. so i didn't know if the isc needed coolant because i know honda's just delete them but i guess toyota's are a bit more finicky, as i have learned haha. i still have the isc vacuum port (the big 1/2" or so one) connected to the intake, pre turbo, as that's where it goes through the stock lines, or if i'm wrong correct me please. what i seem to think, again correct me if i am wrong, is that: a) i really don't need the vacuum for the power steering as i'm never at full lock b) i don't need a/c idle up since my a/c compressor is gone c) coolant lines to the ISC ARE necessary d) the ISC vacuum port goes to intake pre turbo if i am wrong on any of this please tell me, but if this is correct, i can just run new coolant lines to the isc, yes?
Woooooo Hoooooo that's it............. Seeeeee, I told you dudes I couldn't explain it properly :mrgreen Thanx Killer, I thought I was going insane :suicide :mrgreen
haha yea no i visualized it as soon as i read your post. but no it's not slipping anywhere where i can see it, basically what's under the top timing cover. i didn't take off the lower timing cover because i have no way to really access that part of the car right now. would it be beneficial to rotate either cam in either direction by one tooth or would it do more harm than good? i've heard that the exhaust cam should be retarded 6 degrees but that's much less than one tooth, correct? also, now that i am getting a 3sge side feed manifold, water lines will be much easier to run to the TB.
i'm not going to do any of that now obviously i just want to get the car running correctly. for now i'm focused on getting the car ready for it's inevitable 450 mile trip from my house to school, so i can work on it there in class (i got to UNOH, one of the largest and best automotive/high performance schools in the nation).
