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hey guys, recently bought a motor off here and just seeing if anyone has any input on this as its doing my head in ! pretty much just a standard motor rb25/30 wise with twin throttle bodies. it cranked over (when at mechanics) and he bled the coolant and let it run for 30 minutes id say, then now it wont start. it kicks over but the thing wont fire, he said he tested it and hes getting no injector pulse, now ive checked power from the green wire going to injector loom (power) checked to the coil pack loom (power) even under the glovebox that thick pink wire (power) so i have no clue what to do next, im willing to play around with it but in about 2 weeks ill have to get it to an auto elec but i want to save as much cash as i can if i can. cheers guys the link is here.

Pull out the Crank angle sensor, leave it plugged in, turn the power on but don't crank it over.. spin the CAS and listen for the injectors ticking. if you can hear them then its not that if not try to test another CAS in the same way..

Edited by rsx84
  • 2 weeks later...

ok so electrically everything is working, the cam timing was way off as ill show you in the picture, around 20 teeth too much. re-set it today and something still seems wrong, not only it wont start im thinking the cams may have been set wrong too because ive put everything back stuck it in 4th pushed it foreward and it doesnt run freeely, you can feel its grabbing hitting metal on metal on one or two cylinders, i plan on doing a compression test tomrorow to tripple check but i think the motors gone because of how far out it was, going to get it inspected this week hopefully...

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Uh oh, would have bent valves,

From now on before u try and start the motor ALWAYS turn the engine over by hand(using a 27mm socket on a ratchet) that way if it hits the valves and pistons u will feel it and shouldnt do damage. Then u can fix cam timing and try again

unless you can hand crank it freely all the way around you are wasting your time with a compression test. the bolt holding the idler bearing in my 25 snapped it idle losing all power, engine turning over fine there and then again but once it cooled down the exhaust valves in #2 dropped onto the cylinder head. if it won't turn all the way around when hand cranking as per above, take of the exhaust or inlet manifold and feel around in the head you'll soon find the problem... who did the timing?? ie: was it like that when you bought it?

Also the pic really don't help to judge if it was out, line the dot on the inlet cam with the white line on the backing plate on the left on the pic (not the ones at the top) the dot on the exhaust cam should then line up with the other white mark on the backing plate (again not those marks on top) then check your harmonic balancer also shows TDC.. all dots and lines should meet..

Edited by rsx84

Ok the person that rebuilt the top end has marked it wrong and my local mechanic pretty much just swapped the rb30 with the 25/30... he put the markings back to how the engine builder had marked it which now i know is wrong, i did set it all back to factory, put the car in 4th and pushed it probably 3 or 4 full rotations, its still hitting, same as before except now when you try start it and you have your foot to the floor it backfires and you can hear the petrol igniting through the plenum. ive already organised a local skyline specialists to take a look at it and fix anything wrong with it, hopefully only a handfull of valves but will have to wait and see.

when you say hitting, do you mean its hitting but still fully cranking around or is it stopping when your cranking it?? stopping = bad, hitting = still bad i'm afraid. both really means the head comes off the block, replace a few valves and shes sweet.. just got all the parts in to start my full re-build so i know what a pain it is..

Edited by rsx84

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