Please help, Engine vibration ....

[Steve Tinker]

SS + 1 as Matt says.... but,
1) The leaking new bearing seal so soon after replacement is a definate worry - how much is it leaking? Indeed a severely unbalanced flywheel could theoretically twist the end of the crankshaft, so clocking the flywheel is a good idea - I wish you luck as a bad result is going to hurt....

2) If you have muliple missfires on 4 out of 6 cylinders, surely it will also cause severe vibration at high revs - but do you get a power loss too? Changing the 4 coilpacks (or even moving two of them to the "good" cylinders to see if the problem swaps positions on the OBD tool) is a relatively cheap option.
Keep us informed.......

[Sideways Steve]

Well, bad news im afraid

Pulled her all apart again and the new seal is wrecked. The end of the crank appears to be bent, I cranked the engine over without the clutch fitted or the box on so I could watch the new flywheel and it wobbles like a buckled wheel

I rekon as you have said the damaged flywheel has damaged the crank, I just dont know how it has warped so easily being such a short crank.

Either way the engine is going to be pulled apart next weekend when I get a chance to investigate.

The front mount BTW was also shot, however looked quite new so I think its died due to the imbalance issue with the crank.

The way I see it now I have a few options,

1) Complete drop in replacement engine

2) Replace the bottom end as a complete unit using my heads etc

3) Tear down the engine and rplace the crank and bearings (assuming the bearing housings are still intact)

Im looking into quotes for the parts to progress so will keep you all informed.

I rekon im looking at about £1500 to sort this out. I just keep telling myself it will be worth it when its done !

Im just a bit miffed as I sold my 600bhp GTR to buy something "reliable" and now im in here pulling engines apart !!! LOL

[eightsandaces]

Originally Posted by Sideways Steve

Well, bad news im afraid

Pulled her all apart again and the new seal is wrecked. The end of the crank appears to be bent, I cranked the engine over without the clutch fitted or the box on so I could watch the new flywheel and it wobbles like a buckled wheel

I rekon as you have said the damaged flywheel has damaged the crank, I just dont know how it has warped so easily being such a short crank.

Either way the engine is going to be pulled apart next weekend when I get a chance to investigate.

The front mount BTW was also shot, however looked quite new so I think its died due to the imbalance issue with the crank.

The way I see it now I have a few options,

1) Complete drop in replacement engine

2) Replace the bottom end as a complete unit using my heads etc

3) Tear down the engine and rplace the crank and bearings (assuming the bearing housings are still intact)

Im looking into quotes for the parts to progress so will keep you all informed.

I rekon im looking at about £1500 to sort this out. I just keep telling myself it will be worth it when its done !

Im just a bit miffed as I sold my 600bhp GTR to buy something "reliable" and now im in here pulling engines apart !!! LOL

SS, The front engine mount tends to go early on the Boxster, my belief is that is do to excessive heat. Combined with whatever happen to the engine, it's no surprise it's shot. If I were you, I'd look for a used engine in good shape, it might be cheaper in the long run, good luck.

[vipola]

Damn this is very sad to read.. :/
Any way you can get back to the seller because he hidded something??

Tell yourself at least you have the advantage of having a good mecanic background and been able to do some work youself.. imagin the bill if you had it tow fo the dealer and pay them to investigate all that..

[Steve Tinker]

SS
Just be very aware that these M96 engines are very complex pieces of kit - more so than the straight 6 Nissan units.
Before embarking on a teardown, I would suggest you obtain as much info as you can on the complexities / costs / tools etc you are going to need campared to (say) going to Porsch specialists like Hartech or Autofarm for advice.
Whichever way you go, best of luck & keep us informed of the results.....

[Sideways Steve]

Cheers Steve,

I'm aware there complex but not as complex as some of the stuff I have rebuilt

Rebuilt some Rotarys along with upgrades at the same time also done a Mitsi V6 Mivec engine recently and I have rebuilt gas turbines and various other mechanical/electrical systems through my line of work too so the wee boxxer engine is a piece of cake in comparison

Plus I also have the full workshop manual to hand too

Also have all tools that I will need which I have collected over the last few years of messing about with all manner of engines/vehicles.

There was me thinking now that Im an Instrument Tech to trade I would no longer be getting my hands oily ! grrrr LOL

Dont have any comeback with the seller as it was a private sale and sold as seen. On the test drive the car drove fine, although I didnt give it quite as much abuse as I probably should have !!!

My own fault though, and to be honest I actually believe the seller had no idea there were any issues as he was the type of guy who would probably only ever drive below 4000 rpm !!! LOL

[eightsandaces]

SS you're a saint, why? Well I for one think the PO knew exactly what was wrong with that automobile. Sounds like you have an impressive resume to tear down a m96. I would however, heed Steve Tinker's advise as I have read where even full-time mechanics would have a hard time with the M96. Good luck, we will certainly be pulling for you to resurrect the Boxster.