Hey all

 

PTU? what was the nissan recall for (ie what was the failing?) and what are the symptoms to replace this?

 

Underdrive pulley: has anyone got one and has anyone noticed by skimming the flywheel and putting a U/D pulley on if there are any crankshaft pulley balance problems?

 

Ok i lied 3 questions!

 

Can the cranks on the 300zx TT be lightened and/or balanced? someone told me they cant?

 

Many thanks

 

Latz

 

 

Latz.

 

Yes PTU was a recall bu not in Europe - same module i believe with the same fault - not sure the exact technical failing of it but if you do a search it might be covered as someone posted the Nissan Recall list somewhere. Symptoms are car stalling failing to start Etc Basically ignition problems.

 

If you have the flywheel skimmed correctly you should have no balance problems with the UD pulley. Note however the use of a UUD Pulley may cause resonance of the crank and danger to the bottom end of your motor - haven't heard it happen to anyone yet but it is a deffinate risk be mindfull of that before you put one on the car.

 

The 300zx crank is very well made and balanced as stock - I dont think NISMO do a replacement which generally means it is a good one - You 'may' be able to lighten it but i wouldn't fancy many people in the world have the knowledge to lighten it enuff to produce significant gains.

 

I would leave the Crank well alone it is good for 800hp+

 

Hope that helps.

 

 

 

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Z ya

 

Nico91TT

 

 

Dont be a Punk ...

 

In stores this Friday ... Hurry only limited stock remains ;) ...

I think someone said if you buy a new PTU from a uk dealer you still get the older crappy one, but courtesy sell the upgraded model. worth checkin out before spendin any cash.

I also heard that the stock crank is made to very high tollerances and was used in the race cars, maybee that's why nobody has actually had problems from the UD pulley.

You can buy refurb PTU's, so i assume with a little investigation one of the tech guys here could do it too.

smithy

I can repair them (usually), but I won't give long guarantees - they are delicate things inside. For a long term fix I reckon you should buy the replacemnet from Courtesy :- http://www.courtesyparts.com/cgi-bin/miva?onlinestore/merchant.mv+Screen=PROD&Store_Code=CP&Product_Code=22020-00Z32

 

One of the guys on the Aus Forum (www.aus300zx.com) was trying out one from a completely different car recently. Haven't heard how it went though. Might be worth a search.

The new PTU is made by Mitsubushi and fitted to the "newer" model years. Does anybody remember a post that said the new PTU is the same as fitted to the GTO, and available from their dealers at about half the price of the same part provided through the Nissan dealer? I think the post had the part number too.

 

Sorry, no time for the search, but thought you may like to take a look. Geoff

My car is dead and it looks like the PTU.

I called Nissan Leeds and they quoted £320 squids. I gave them my old part number and they called me back with the price and said that part is no longer available and has been replaced with a new item so looks like you would get the new one here.

 

£320 is outrageous, the Courtesy part is $178 + shipping, which would make it about £150 I reckon. (Which is also outrageous)

Chris,

Just had a thought - Shrek could send you my spare to prove yours is dead. (I WANT IT BACK THOUGH !!!!)

 

Andy,

Do you want me to send it to Chris??,if so i'll need Chris's addrees.

 

Check your mail Andy.

Ken

If he wants it ....

Thanks guyz

 

it was really appreciated for all the info. one more though nico:

 

what do you mean by resonannce?

 

Latz

Now look what you've gone and started Nico

 

Hmmmm how to describe resonance....

 

A guitar string resonates - resonance is the natural frequency of vibration that a component has - in other words this is the frequency at which the component likes to vibrate. At the resonant frequency of an object, the amplitude of the vibration is at its greatest (it moves the furthest from the centre line on each vibration 'stroke').

 

A crankshaft also has a resonant frequency - in fact everything has a resonant frequency. With a crankshaft, each time a piston fires it sends a shock down the conrod which is then transferred to the crankshaft. At a certain revs, the rate of pulses from the conrods is the same as the natural frequency and the crankshaft has a possibility of litteraly shaking itself apart and doing considerable damage!

 

Due to this, most engines have what is called a harmonic dampener (mounted in the bottom pulley) which stops the vibration getting out of control. Underdrive pulleys do NOT have a harmonic dampener built in to them and so resonance could, in theory, be a serious problem resulting in engine destruction. The dampener isn't even a complex part - it is simply a rubber ring holding the outer and inner parts of the pulley together - this way the outer part of the pulley is not directly connected to the crankshaft.

 

Any more questions? Want me to explain Einsteins theory of relativity???

 

Nico - you owe me one for that - my fingers are now killing me

 

CheerZ,

 

Andy

Thanks duffo

 

long time no speak. appreciate the advice though m8

 

Latz

Thanks for the offer Andy but Iain MAC1 is coming round at the weekend to try his in my car. If it is faulty I might just send it to you to do your magic before buying one from the U.S.

How long do Courtesy orders take to get here?

 

Courtest are usually very quick. Typically under a week - they use expensive FedEx and you get stung for the tax(es).

Courtesy are usually really fast at getting parts out, I would definately reccomend them!

 

UK customs can be a real pain though... I've been waiting on a package that's still in customs at the moment - it's been delayed at UK customs for over a week! They want individual descriptions of each item or something daft like that. FFS don't they know what an oil filter or a spark plug is?

 

John

Muahahahah Nice one Andy - You could have also gone with - Destructive Vibration it aint essentially correct but they get the picture you can save you wrist muscles for your other fav activities hehe

 

 

 

 

------------------

Z ya

 

Nico91TT

 

 

Dont be a Punk ...

 

In stores this Friday ... Hurry only limited stock remains ;) ...

I got UD pulleys no probs. good mod. Pete at SE doesn't reckon any crank problems. Resonance not really an issue.