My Gtr Horror Story

[Bankrupt]

Hi there people. Just thought I would share my problem and see what you guys think.

I recently purchased an r32 GTR with some reasonable mods.

While adjusting the belts on the weekend I noticed the harmonic balancer was loose.

Sure enough I pulled the bolt out (by hand) to find the keyway on my crank

all smashed up.

I seem to have found it before too much damage has been done, as the nose on

the crank is still true and round.

The previous owner had the timing belt done by a so called reputable workshop, who did the bolt up without loctite.

The motor was making 340kw before this, so I would like to avoid

stripping the motor (if possible).

I'm currently looking into machining the balancer out and installing a

torque coupling in an attempt to keep the motor together.

If anybody has any experience with this, advice would be much appreciated.

[TTT]

lol.. mate that is not a horror story.

Could have been but you luckily managed to change its course.

[Frosty]

where is the horry story?

glad u got it before all got to bad tho.

[GTR-N1]

...timing belt done by a so called reputable workshop,...

The said workshop:- was this work done within the last 12 months?

If so, how long do they warranty their work (whilst you call them)?

Your car is on their computer right?

By the way Bankrupt, welcome to SAU!

[Bankrupt]

Was done 11 months ago, and I don't have receipts ect. Plus the previous owner is friends with the owner of the workshop so I doubt he would be any helpful in trying to blame them.

Thanks Terry, I'm new to SAU but not new skylines so have used the forums for info in the past.

Yea if it wasn't for a noisy ac belt I would be in a lot more trouble right now.

[GTR-N1]

I'd still rock up to see if 11 months down the track, that rectification is able to be completed!

They can only say, "No". Besides, as you walk in with a smile on your face, they may see you as 'potential business'. It's hard times you know.

[Missileman]

Oh and loctite on the crank bolt is not recommended, just use the correct torque or slightly more if the KW has been increased.

[Bankrupt]

A photo if anybody wants to see.

340nm with loctite I have been told by engine builders.

It's a very frustrating problem to have considering the rest of the motor is in good condition

[MrStabby]

ImageUploadedBySAU Community1363746449.669915.jpg

A photo if anybody wants to see.

340nm with loctite I have been told by engine builders.

Workshop manual says 446-466 Nm lubed with engine oil for RB26. FWIW lubing the thread reduces the required torque to get the correct bolt stretch by about 25%.

The engine builders who stated 340nm may not be worthy of your trust.

[Bankrupt]

Thanks Mr Stabby,

I would assume that they use this torque due to using the loctite as a lubricant.

I will most probably use the workshop manual values just to be safe

[ezy_09s]

No wonder the bolt was loose .. There are no threads on the crank anymore.

And the keyway is farked . I would be getting the engine out personally .

[MrStabby]

Thanks Mr Stabby,

I would assume that they use this torque due to using the loctite as a lubricant.

I will most probably use the workshop manual values just to be safe

IMO you're being too generous to them by assuming that - there's no way loctite will be as good a lubricant as engine oil, so with loctite it would require more than 466Nm.

There been a number of other threads on here about this issue - search and you'll find them. They have some answers....but none easy IIRC.

[GTRsean]

Threads don't start till about 20-25mm into the crank hole

[Greekos]

in a way your very lucky, i have seen this mistake before, i have even seen it kill a motor, this is one of the first things my tuner checks when going over skylines in his workshop thats how common it is.

[ezy_09s]

Threads don't start till about 20-25mm into the crank hole

Yeah your right Sean , the threads start 23.5mm in from the end of the snout .

I was thinking of my big block Chevy crank where it's threaded right until a couple of mm from the end.

[Shoota_77]

There is a very good chance the oil pump could be on the way out too as the extra reverberation from the balancer "clacking" back and forth wears the leading and trailing edges of the inner pump ring which eventually causes them to shatter due to the thinning of the ring and the trauma the harmonics causes.

I had an oil pump go which I presume was caused by the crank bolt being very loose.

It's a prick of a job but to be safe I would pull the engine out and check/replace the oil pump especially if a standard or N1.

That's no horror story either. There will be a lot worse to come!!!!!

[Tommy Kaira RL]

I had this happen on a V8 I had rebuilt. The harmonic balancer actually broke the end of my crank off. Then when the idiots fixed it under warranty they never cleaned the journals out properly on the next crank which caused it to wreck the big end bearings. I had the engine out 3 times that year.

I would be taking it out to be safe.

Luckily the reputable business at the time is no longer around.

[Bankrupt]

Yea oil pump is my main concern.

I know I can put the balancer on to the point that it won't come loose again with a taper lock coupling, but every time I drive it ill be scared of oil pump failure.

Looks like it might be sitting in the shed for a bit while I save up for a set of forgies.

Does anybody think its worth buying a new billet crank rather than going r33 crank etc?

[Greekos]

take your car to someone who knows skylines in your area and have them hook a oil pressure gauge up then you'll know good luck

[Shoota_77]

Plenty of guys making huge power with well balanced standard cranks so i personally wouldn't waste the money on a billet crank unless I was going a stroker.

Do that!

With regards to Greekos' comment above, nothing wrong with checking oil pressure but most of the time the engine will have full oil pressure till she goes bang, then you've got 0 pressure!