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apologies if this is in the wrong location, not sure where to post this.

My Rb25/30 in my vl refuses to start.

Was previously running as a single t3 setup, moved to bigger hotside now wont start.

Car currently cranks but gives no hint of starting.

Have checked the following:

Has Fuel - Have gone as far as removing injectors to ensure that each is firing.

Has spark - have removed all 6 coil packs with plugs in and have seen spark from each, looks quite strong.

Has correct timing - both cam gears line up with markings as well as the balancer is lined up. Even removed the intake cam cover and ensured that the 1 valve is pushed down at the moment of TDC (had originally had it 180 out but this has been fixed)

Has Air - removed cooler piping, just straight opening from the TB.

Has compression.

Things I have tried:
- The old start ya ******* in the intake, still no sign of start.
- Fuel directly in the cylinders, still no signs.

Is run by a Wolf ( please dont suggest that I should bin this, was working previously)

I appreciate if anyone has any other suggestions for me to try? I am all out of ideas.

Need anymore info let me know!

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https://www.sau.com.au/forums/topic/454099-rb25-wont-start-please-help/
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Yeh CAS seems ok. Lined up where previously working. If I take CAS out and spin it ticks the inj so I presume it is functioning. I do have two CAS that both worked and no difference between either. Surely I havent broken both by having them sit around!

Anything else you could think of?

A suggestion, try to list the sequence of events, otherwise we're just guessing.

eg

Car was running perfectly and I only fitted a new turbo, now she won't start.

OR

Fitted new turbo, manifold, cam belt etc, etc

Just a heads up, TDC/firing on No1 will have all No1 valves closed.

TDC/firing on No6 will have inlet and exhaust valves swapping over on No1.

Thanks for the reply. WIll have to double check than but have tried the timing with all 3 marks lined up and than also rotated the crank one turn and tried lining them up there, but to no avail. Just to clarify, I need to have the valves on no1 on both sides closed when its a TDC and than put the belt on there?

Sequence of events is a little more to it than that so ill list them out.

It was running perfectly as a 25/30 with a t3.

Than upgraded the following:

- Manifold plus twin t

- 044 plus surge / top feed 650cc inj / new FPR.

- changed rb30 oil pump to the rb25 oil pump

- changed balancer over to a smaller one without a air con pulley.

- went to 80mm TB

Coil packs cas etc are them same and std.

Still using the wolf.

Any help from here is appreciated

you are correct, ignore my comment on turbo. it has a small one now it has two big ones, is that enough info?

In regards to inj, no I have not made any adjustments in wolf.

Car has not made a splutter, so I am not sure this would effect it from trying to start?

Either put old injectors back in or get someone to change settings in the ecu.

They spray way too much fuel therefore car doesn't start.

I win this thread.

Just curious how big were previous injectors?

Edited by Ben C34

Cant swap in old ones as they were the std side feed and I've got top feed with new lines etc. Dearly noted will get the wolf updated for the new ones. But seriously would having to much fuel mean the engine would not even try to start? The issue seems more sinister than that. Any more ideas let me know mate

I completely agree with ben with the larger injectors without a tune wpuld deffinatly be flooding the car and causing it not to start. I noticed you have a aftermarket fpr. I had something similar happen to me when i changed my injectors over from stock to 750cc top feeds what we done was turn down the fpr reducing the fuel flow and that got it started and got it to the tuners. So maybe even give that a try. I had mine turned down to 1bar

  • 7 months later...

Have checked the following:

Has correct timing - both cam gears line up with markings as well as the balancer is lined up. Even removed the intake cam cover and ensured that the 1 valve is pushed down at the moment of TDC (had originally had it 180 out but this has been fixed)

But you said that you had fixed this....when I [just now] read the thread my first thought was timing is out 180'.........but you said you'll fixed it so I - like many others here - discounted that idea straight away.

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