r33 timing issue

[Cozzamb]

i have a rb25de and have recently done the water pump after it blew but now the car is really down on power i put the belt back on and lined it with all the marks and even set it to 15 degrees with a timing light but it still won’t rev could it be the belt tension? not sure what to do

[GTSBoy]

Take it apart and check it again.

[Cozzamb]

i have man about 4 times still can’t figure it out

[tridentt150v]

One thing I will say, its nothing to do with belt tension....unless its that loose its skipping teeth.

You need to check that you are using the right marks on all 3.

[MBS206]

Will back up what trident said.

Pull it again, and check the marks. Take photos of all the marks and post them.

Also check the harmonic hasnt spun the outter section which has the timing marks.

Also check you've reconnected everything properly, all pipes, cables etc.

Do you have adjustable cam gears, or factory ones?

 

When you say it won't rev, does it start all perfectly normal, but then you try and press the accelerator and it won't rev up?

Or you're having to start the motor with throttle, especially a lot of it?

If the latter, I suspect you have one cam advanced massively, another retarded massively, and you've done this by lining the gears up on the wrong mark. Been there, done it myself on an RB25DE head.

Car would start and run a bit, but was basically at WOT only it would run (and wasn't much over idle RPM). I also had an aftermarket ECU, so was running MAP not AFM.

[Cozzamb]

yeah as far as i know all 3 of the marks are lined up (i’ve checked about 4 times because of this issue) i will take it apart tomorrow and post it on here

when turning the car on from cold i have to use throttle but idles fine. when revving when driving it almost spatters and won’t go much higher then 3000rpm

i have factory cam gears

the harmonic balancer has definitely not spun

 

[joshuaho96]

  On 11/09/2023 at 10:03 AM, Cozzamb said:

yeah as far as i know all 3 of the marks are lined up (i’ve checked about 4 times because of this issue) i will take it apart tomorrow and post it on here

when turning the car on from cold i have to use throttle but idles fine. when revving when driving it almost spatters and won’t go much higher then 3000rpm

i have factory cam gears

the harmonic balancer has definitely not spun

 

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Have you actually verified TDC cylinder 1 is where the balancer says it is? Has this engine been rebuilt at all?

[MBS206]

  On 11/09/2023 at 10:03 AM, Cozzamb said:

yeah as far as i know all 3 of the marks are lined up (i’ve checked about 4 times because of this issue) i will take it apart tomorrow and post it on here

when turning the car on from cold i have to use throttle but idles fine. when revving when driving it almost spatters and won’t go much higher then 3000rpm

i have factory cam gears

the harmonic balancer has definitely not spun

 

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Double check the AFM is plugged in too, AND both temp sensors are plugged in too.

 

Do a huge double check for air leaks too.

[Cozzamb]

not sure how i would verify TDC for cylinder 1 as i’ve just been doing everything off the workshop manual 

the engine has not been rebuilt 

all sensors are plugged in

[GTSBoy]

  On 12/09/2023 at 12:56 AM, Cozzamb said:

not sure how i would verify TDC for cylinder 1 as i’ve just been doing everything off the workshop manual

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Spark plug out. stick/screwdriver in the hole. When it stops going up and starts going down, that's TDC. Very hard to catch the exact top because the motion slows down as it dwells across the top, so you end up needing to look at the height of the indicator a few degrees either side of where you think TDC is. If it is at a certain height and rising at some indicated angle and then it is at the same height and falling at some other later angle, then halfway between those angles is true TDC.

[blind_elk]

Sometimes, the timing light indicates the incorrect timing. How did you actually measure / set timing?

[joshuaho96]

  On 12/09/2023 at 7:11 AM, blind_elk said:

Sometimes, the timing light indicates the incorrect timing. How did you actually measure / set timing?

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This is worth thinking about, personally I hate worrying about whether the inductive loop or whatever is all set up correctly. I just use a spark plug wire on cylinder 1 instead.

[Dose Pipe Sutututu]

Is your front timing cover back on? If not I hope you've spaced out the CAS.

Is your CAS still in good condition?

[Cozzamb]

yeah timing cover is back on the cas works fine 

[Dose Pipe Sutututu]

  On 12/09/2023 at 9:22 PM, Cozzamb said:

yeah timing cover is back on the cas works fine 

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Just swap it out anyway