Hi everyone. Just a bit of an introduction, My name is Darrel and I’m quite mechanically inclined but new to the GTR scene, just got my car, BCNR33 V Spec about 3 weeks ago and the very same night I got it the engine took a dump on me.
What happened was I was cruising around in 60 and 70 kmh zones with a friend and went onto the highway and did a couple of hard pulls (if you can even call it hard, rolling start from 2nd into 3rd gears only and only got up to 140 kmh for 2 seconds unkowingly). Went back onto 70 kmh zone and cruised around for a bit before pulling into a gas station, turned off the engine and the turbo timer started counting down from 1 minute, everything was fine at this point. We decided to go across the road to get some supper and when the engine shut off I started it again, that was when the problem started.
Started hearing a loud knocking noise which increases with RPM (depressing clutch does not affect it) from the engine and idling was rough, even stalled as I was backing up out of the parking lot. After a few minutes stopped at the traffic lights the idling and noise got so bad I just pulled off the road. I did not get a video of the sound but my first thoughts were I’d spun a bearing & suffering from rod knock (I’m inclined to say that rod knock this severe doesn’t happen instantly but I could be wrong). So let the car sit for half an hour and checked the oil, it was low, on the L of the dipstick, still suspecting rod knock. Added a liter of oil and started the engine again, struggled to start, same noise, same rough idle, misfiring, stalling & quite a lot of blue smoke from the tail pipe. Gave up and parked the car, towed the car home the next day and have since started taking the engine apart slowly to pinpoint the problem so I can get a rough estimate of the damage cost. After listening more closely, sounds like the knocking is coming from the top of the engine instead of the bottom.What I’ve done and found so far:
1. Checked coolant and engine oil, they have not mixed.
2. Shined a light into all cylinders, did not look like anything (compressor wheel) had been sucked in & chewed up, checked plugs, all fine except for being stained from running rich.
3. Did dry cylinder compression test, all tested 130+ psi from cylinders 6 to 3, cylinders 2 & 1 got 20+ psi (at this point I’m inclined to say bent valves from the noise it makes but could also be blown head gasket but oil and coolant have not mixed). Did wet cylinder compression test on cylinders 1 & 2 went up to 35 psi (could it be blown piston rings which explains blue smoke and misfiring?).
4. opened cam gear covers to check if timing had jumped, found that on IN: 1 tooth retarded & EX: 1 tooth advanced (in addition it has HKS cam gears & EX has been retarded 2 degrees by previous owner). This could cause rough idle & stalling but could it be enough to cause a piston/valve collision?
Next course of action is to redo timing & see if it improves. Engine has HKS cam pulleys, Power Enterprise timing belt, & from what I can tell, the engine internals are stock, has a Trust intercooler, brass button clutch (don’t know what make/model yet but it is slipping slightly), turbos look stock, boost increased to 14 psi running on 98 octane BP petrol.
It is apparent other things/mods have been done to it by previous owners but they have been removed prior to being imported to Australia last year. I have no experience at all with RB26’s so I really need help here and I really hope everyone in here can lend a helping had to a newcomer to GTR’s & any insight, opinions & experience are welcome & will be much appreciated. Really really hope you guys can help, thank you in advance & have a nice day, cheers!