rb25/30 wont run

[dnb]

hey guys.

a mate of mine has a rb25/30 which has been on the road for a few months.

all of a sudden it got low oil pressure,we changed the pump and she still wont run.

it sounds like a timing related problem but ive checked everything and its all ok.

when it cranks the engine will fire and it spins backwards a little bit.

im thinking that maybe the lifters are dry? would this cause such a problem?

any help much appreciated guys:)

[DoughBoy]

Too much advance on the timing?

[BBQ]

hey guys.

a mate of mine has a rb25/30 which has been on the road for a few months.

all of a sudden it got low oil pressure,we changed the pump and she still wont run.

it sounds like a timing related problem but ive checked everything and its all ok.

when it cranks the engine will fire and it spins backwards a little bit.

im thinking that maybe the lifters are dry? would this cause such a problem?

any help much appreciated guys:)

Check to make sure you haven't sliped a tooth on the timing belt when you did the oil pump change.

[blind_elk]

If its kicking back, then the timing is TOOOOO advanced. You shouldn't be able to get it so advanced because of the half-moon tabs in the CAS, but the camshaft side has been known to part company, and then you can set the CAS wherever you like.

[dnb]

camshaft tab has been snapped off. im pretty sure i lined it up properly. will fit another cam to rule that out.

does anyone know how many teeth should be from dot to dot with the pulley above the water pump?

[dnb]

thread from the dead.

the oil pressure problem was tracked down to the external vct line being too big.

URGENT

can anybody get me some dot to dot figures for the rb25/30 with the 152 tooth timing belt.

thanks in advance:)

[Cubes]

There's no need for a dot to do figures..

Line it all up at TDC then tweak the cam belt and its tension. Simple as that.

Remember everyones tension location will be ever so slightly different not to mention the tension they place on it and if they have used two tensioners in stead of just one, so don't use the teeth counting method, it sucks.

Edited December 28, 2005 by Cubes

[dnb]

yeah i realise that.

my problem is we have just put a new rb25/30 in my mates car and it wont fire.

it has fuel and spark.

the engine sounds funny when it cranks and seems to spin very easily.

my other thought is possibly the hydrualic cam followers are not primed up and the valves arent opening much,if at all.

it is also running a microtech which was running the rb25 previously.nothing has changed there.

any help seriously appreciated

[Cubes]

Double check everything....

Ensure the cam timing is correct, ignition timing is correct (no guesses and if it double pulses and reads funny double loop the wire over and it should read right), double check fuel and spark.

Mine has lifters that had been bled, upon starting the motor it idled fine but ticked for quite a while until it got some rev's in to it then it was nice and quiet.. So no it won't be the hydraulic followers.

Its probably something silly, if its spinning over quick has it got spark plugs in it?

[dnb]

yeah its got plugs lol,but thats exactly what it feels like.

i just put it to tdc and each cam pulleys dot to the mark on the timing cover back plate. so i assume cam timing is correct.

ignition timing cannot be checked yet because the bloody thing wont run lol. but its the same map that was previously in it so it should run(made 456rwhp as a 2.5l)

[Cubes]

Sorry I meant CAS ign. timing, the problem is that can't be checked until the motor is running also.

If its kicking back then its way way too advanced as previously mentioned.

[dnb]

no sorry the first 5 posts are from ages ago, different engine lol,

[MonstaS4]

I havn't tried this, but surely you could still check ign timing while the engine is cranking over? If you've got spark, then the timing light has to be getting a signal. It won't be accurate, but you should be able to start it.

You may have fuel, but do you have pressure? Can you hear the injectors switching?