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Hi all, I'm unsure if this is where to post this ( am a newb ) looking to change that though. Ill give a little background information.

I bought an r33 gtst s2 a few months back, with no issues other than it was running a bit rich, needed a good tune. I drove the car from bundaberg to Brisbane ( 4 hours ) and it went fine, was parked up in Brisbane and left till I got back home after a few weeks.

This is when the trouble started. I went to fire up my car after sitting. It kicked over at first. But idled terribly, Untill after 10 or so seconds.. It died.. It didn't sound healthy at all.

I initially thought it was out of fuel ( it was below a quarter on the gauge and I have an aftermarket fuel pump Bosch 040 so I thought the pickup may not be reaching fuel. Fueled it up and tried again. Nothing. Primed it a few times, nothing. Cranked and cranked. Occasional splutter then nothing.

I am currently in caboolture so I decided to take it into a shop. I'm not mechanically retarded but some things are out of my league.. I took the car to rpm mechanical in moray field and they have said they say that everything checks out. It's getting fuel, spark is strong, and good airflow. They said they went to basics. Did a compression test and said that it was low and my engine was dead.

My question is, should I get a second opinion? Does this sound like my problem? Also. Is there anyone on sau around Brisbane/caboolture capable of doing a compression/leakdown test? Be able to tell me what's going on with my baby? I'm willing to pay..

If not. Are there any reputable tuners/ mechanics around this area? Are rpm reputable.

I'm looking into a new rb25det motor but if anyone can help out first I'd be more than appreciative!

Sorry for the long post, I'm in an emergency situation here as I need this car on the road!!

Any help would be appreciated

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Is it leaking fluids? Ask them to show you the comp test results. I don't think a sitting engine for a few weeks coild cause it to seize. Have you looked for oil in water or water in oil? A comp test is a pretty solid test but id ask for results or watch them redo the test.

Hey thanks for the reply. I notice this morning a tiny amount of coolant I believe in the garage. Another few drops on the car carrier after it was taken to the tuners.

I was talking to a friend and he said because it was running rich and the size of the injectors ( 600cc ) it might have suffered fuel wash? And that may be causing the low compression. It's an option I guess.

I didn't get much from the tuner I will try and find out tomorrow. He was quite vague on the results just. It has compression but it's low. Didn't tell me if it was any cylinders in particular or the whole range, didn't do a leak down test etc.

I just don't understand how it can go from running to dead just by sitting. The coolant was a little worrying. I did look at the oil this morning and from memory it was about half on the dipstick, but didn't look milky. It looked quite thin. Dripped off the dipstick iir. Maybe fuel in the oil?

Would you have a respectable mechanic tuner in the area I could go to for a second opinion?

Thanks again

Hey thanks for the reply. I notice this morning a tiny amount of coolant I believe in the garage. Another few drops on the car carrier after it was taken to the tuners.

I was talking to a friend and he said because it was running rich and the size of the injectors ( 600cc ) it might have suffered fuel wash? And that may be causing the low compression. It's an option I guess.

I didn't get much from the tuner I will try and find out tomorrow. He was quite vague on the results just. It has compression but it's low. Didn't tell me if it was any cylinders in particular or the whole range, didn't do a leak down test etc.

I just don't understand how it can go from running to dead just by sitting. The coolant was a little worrying. I did look at the oil this morning and from memory it was about half on the dipstick, but didn't look milky. It looked quite thin. Dripped off the dipstick iir. Maybe fuel in the oil?

Would you have a respectable mechanic tuner in the area I could go to for a second opinion?

Thanks again

Hey people thanks for the replies.

I've recently got the car back from the shop and after asking them if they had checked the timing of the can gears and said yes, I was about to start ripping the head off and putting a new one on.

I took the timing belt cover off and turned the crankshaft till it read 0 degrees at the crankshaft. And the cam gears were way off there marks, probably 20 degrees ATDC. When the can gears line up to their marks, the crankshaft reading is 340 degrees.

Is this right? Or is it way out? I thought any retardation was meant to be before tdc. I have heard numbers from 15 degrees to 20 degrees. But I'm at a loss here.

When setting up all the gears should all the marks line up and it be on 0 degrees on the crankshaft?

If so, could this be the reason behind my car not starting / over fueling?. I believe there was a bit of knocking when I first turned it over.. So is it safe to assume my pistons could have kissed a valve? And in that case.. How much damage am I looking at?

Hey guys, just a quick update, ill keep updating till the problem is fixed and my car is running again.

I picked up a head and had it reconditioned, looks like new, the boys doing the replacement comp tested it this morning.

Looks like the time was out enough for the valves to be bent. So I got a new head

3 angle valve job, new springs, etc.

Comp test was done this morning.

Cyl1 @ 70

Cyl2 @ 60

Cyl3 @ 90

Cyl4 @ 70

Cyl5 @ 70

Cyl6 @ 60

Pretty shit if you ask me.

The bloke is pulling the head now, he thinks the pistons / bottom end is fine. Going to check it out though.

While doing the test there was no more knocking, I think the pistons have bent the valves enough to miss now.

All in all not looking to good. But hopefully she'll be running this arv! Thanks for the replies. I might even through up a few photos, time permitting of course lol

Alright, so the latest update is this.

Went through the process of taking off the head. Taking everything off, got to taking the timing belt of an noticed a lot of play between rotating the crankshaft, and the timing belt moving the came gears

Pulled the harmonic balancer off.. So very hard to get off.. Got it off and seen some damage.

Pulled the timing gear off of the crank and the key and keyway had been smashed. Metal dust everywhere, basically there was two to three teeth of play either side of where it should sit.

Crank out..

To add way more salt to the wound, pulled the head off, to check the rest..

Valves smashed, my forged pistons were battered dints everywhere, and there was an unruly amount of play in them. All the bores scored and the 6th cylinder piston crown was blown out around the edge.

Basically. Everything that could go wrong. Went wrong. I have a sparkling head now, to go on a blown bottom end.

Oh well.. Good time for that manual conversion, anyone got a spare s2 rb25det lying around near Brisbane??

Lol I wish I had of giving it a hiding Kane, at least then I would feel like I deserved this! But I didn't :/

The reason it bent the valves is stated above mate. The keyways that held the timing gear on the crankshaft in place and tight, had flogged out enough that it put the timing out. And put it out enough for the valves to interfere with the pistons.

It was just a very unfortunate way for things to go. The keyway would have broken down over time.. A long time. But wasn't noticeable till the straw that broke the camels back I guess,

It was probably the reason why it was starting to play up. Retarding the timing over time as the gear flogged out more and more.

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