Explosive engine?

[Hagasan]

There was no noise before the power loss - i'd argue I heard no noise during the engine bogging down either I didn't have stereo on and the exhaust is fairly quiet at cruising speed.

If you have a tip on an engine then please let me know so I can start gathering my options. I see two on ebay.

PM sent to you

[Hagasan]

Yeah I really didn't feel anything off, it felt like.. a fuel pump dying on another car, just stuttering and gradually all the power being lost.

Pretty bad luck i'd agree, i've owned it for give or take six months, paid a premium for low mileage car, absolutely stacks of history all from Honda dealerships, great condition, spent 3-4k on various tweaks, repairs, preventitive maintanence or upgrades and now looking at a replacement engine. I'd like to say I took it on a european tour or to the track but it's had a really easy low mile life with me.

Where did you buy it? From a dealer? If so, depending on the useage/minimal mileage you have done (if it's low) and proof of receipts (showing responsible ownership) for your work etc.... it might (?) be possible argue legally as not being "fit for purpose" but could be a real struggle though.....

[Tokyo-Joe]

Private sale unfortunately, to be honest the seller wasn't a chancer he was a genuine guy and I wouldn't want to sting anyone six months later. As far as he would know I could live at Santapod and have been drifting it

[Hagasan]

No. no I quite understand. A car from a dealer on the otherhand (who in the eyes of the law would be deemend an expert compared to you or I) should supply a car fit to be used for it's designed purpose. If you had only done a few hundres miles since purchase and then this happened, this is where I'm saying you may have had a case against the dealer....

all irrelevent now anyway....

[Kaz-kzukNA1]

Hi, Tokyo-Joe.
Sorry to hear that you had crank pulley failure.
It is very common and for me, it is one of the ‘must’ items to be replaced during the TB service.

I hope I won’t be annoying you by the comments below but for the sake of other NSX owners and the potential future ones, please allow me to remind the importance of replacing the crank pulley at the time of every TB service.

.......
From the compression point of view, you were running the NSX up until it stopped and from what you wrote, sounded like no major mechanical noise, big smoke, etc just before it stopped so seemed to be very unlikely to have compression issue unless your crank pulley weight chewed in to the timing belt (TB).
You can check this from the top or bottom of the engine without cranking the engine.......
Kaz

Although I mentioned the crank pulley in my post above, I can understand that you didn’t notice it considering the state of your mind when you had your NSX sitting in front of you at the side of the road.

Addition to the brake, tyre, Oil, Coolant, etc, checking the crank pulley is one of the things that I always do before carrying out any test driving sessions with the owner at the time of my Health Check service.

In the past, I found two NSX within one week showing the crank pulley about to fail and just recently, managed to save one very lucky owner.
http://www.nsxcb.co.uk/entry.php?401-NSX-Health-Check-Service-–-Day-1


By the way, I will keep using the word ‘crank pulley’ because that’s what it says in the Workshop manual as well as in the Parts list.
In fact, it is called as crankshaft pulley.
The one inside the TB cover driving the TB is called as TB drive pulley.

Also, while the weight on the crank pulley is acting as the harmonic balancer for most of other production cars, for NSX, the main purpose is to protect the TB itself from the resonance frequency at the specific rpm.
The topic in my 'NSX Technical and Service Information Index' thread; Crank Pulley, the story behind...



http://www.nsxcb.co.uk/showthread.php?6286-NSX-Health-Check-Service/page28&p=72032#post72032
The crank pulley doesn’t fail all of a sudden. The process is very slow.
As you can see from the photos in the above link, the weight will first start to dislocate slightly at a very small section and start to create an angle to the crank pulley. It will keep dislocating slowly and then, it will exceed the critical point and any sudden changes in rpm will cause the weight to completely dislocate itself from the pulley.
From this point, it doesn’t take too long before the pulley starts to chew into the TB cover.
Unfortunately, until the TB is actually damaged and jumped the tooth to cause valve timing issue, you won’t feel any noise, vibration or anything while the engine is running.
Some people managed to hear the metal like scratching noise just after stopping the engine because the dislocated weight was still spinning by the inertia for a short period creating the noise.
Because of this, I’m afraid unless you have requested to replace the crank pulley to the new one and the actual new part failed soon after that, it is very unlikely to be covered by any sort of warranty.


So, please-please replace the crank pulley at every TB service and if you track your NSX or have aftermarket header/exhaust or any other parts radiating more heat, please check it regularly.


Lots of good people at Norton Way so I won’t worry about the process.
For your reference, if the TB jumped just a single tooth, your valves may be safe but from what you wrote, there is a chance that you have already bent them.

I won’t replace the engine just because the valve was bent. The valve itself is not that expensive and the biggest cost would be the labour charge. You also seemed to be happy with your engine for the last 6 months.

Once the new parts are on the engine, they will probably carry out the leak down test on each cyl. You are meant to warm up the engine before the leak down test but for bent valve check, there is no need as you will see huge difference between the good and bad cyl even when the engine is cold. You just turn the engine by hand to set each cyl at TDC so very unlikely to cause further damages including the valve seat even the valve is already bent.

While in there, I would recommend replacing the Water Pump (WP) if it was not replaced during the last TB service and if your engine has done more than 60K miles in total, you may want to replace the LMA if yours is the original design. New desin LMA on the later models will last much longer but you must select the correct parts no. for your engine spec.

Hope your NSX will be back on the road in the near future.

Kaz

[Tokyo-Joe]

Okay so I got a full assessment;

The crank pulley failed causing damage to the cambelt cover, cambelt and water pump. However it did not fully detach and is still spinning on the crank. Because of this they reckon it has not damaged the engine any further, they had the heads off and inspected the valve clearances, found they were okay.

So a mixed blessing, they are looking for £2017 to put it right with new water pump, cambelt, crank pulley, cambelt cover and labour. Does that sound reasonable?

[NSXGB]

If that's including all parts at uk prices, inc vat?, that sounds a good deal. The head gasket set comes in at £860 rrp on its own. if they are ok with it you can save yourself quite a few shillings on that if you get the parts from the USA.

[Hagasan]

Okay so I got a full assessment;

The crank pulley failed causing damage to the cambelt cover, cambelt and water pump. However it did not fully detach and is still spinning on the crank. Because of this they reckon it has not damaged the engine any further, they had the heads off and inspected the valve clearances, found they were okay.

So a mixed blessing, they are looking for £2017 to put it right with new water pump, cambelt, crank pulley, cambelt cover and labour. Does that sound reasonable?

If that's including all parts at uk prices, inc vat?, that sounds a good deal. The head gasket set comes in at £860 rrp on its own. if they are ok with it you can save yourself quite a few shillings on that if you get the parts from the USA.

So the cam belt didn't break? That's a big relief if it's not an engine out repair.....pricewise....well the US parts option is probably more grief than it's worth on this occasion as the car is in their garage. I'd imagine they'd want it off the ramps fairly soon? If so then could they store it awaiting parts or would you have to flat-bed it home then back? The parts from the US are going to realistically take three weeks.

You've got to remember also, they did look at it right away rather than having to book it in and wait days as well.

I agree with Simon that the price is fair for UK parts and it's probably worth going ahead if you can afford it as it will be done sooner rather than later.

I would just get some sort of agreement that they will replace the expensive gaskets etc as required (some places just re-use) and confirmation that they are sure the diagnosis is correct so you don't pay a hefty bill and a fault materialises once back on the road a few miles. Hopefully if the belt didn't break you are lucky and should be good to go...

It sucks I know but I guess it could have been much worse!?!

Hope you're up & running soon..

[Tokyo-Joe]

Yeah that's all Honda UK prices straight from the dealer. It's mostly labour I think.

I have given them the go ahead. They reckon it'll be a couple of weeks to get the parts. An expensive lesson to check the crank pulley.

[nobby]

hi mate

really sorry to hear about your problem ... good to hear not too much damage appears to have been done.

as kaz stated a very important check to do, even though my car had fairly low miles considering its age as part of the refresh work carried out based on reading info on here and on prime the pulley was replaced ...turns out my pulley taken off showed no signs of wear but better safe than sorry

hopefully ur back on road soon