Prelude to a build

Post by **Merlin** » Mon Dec 11, 2023 8:55 am

On my old 5th gen the crank pulley came apart, no damage was done and even the lower cover was ok.

Are you going to get a brand new crank pulley or fit a 2nd hand one?

Post by **vanzep** » Mon Dec 11, 2023 9:59 pm

same happened to me on my old BB4 - bolt came loose.
it was all ok once new parts fitted. no damage done.

Post by **Merlin** » Tue Dec 12, 2023 8:34 am

vanzep wrote: ↑
Mon Dec 11, 2023 9:59 pm
bolt came loose

That's why I loctite'd my crank pulley bolt on my new 5th gen.

TitzonToast · Post by **TitzonToast** » Tue Dec 12, 2023 8:01 pm

Thanks for all the replies lads. I still haven't gotten down to my unit to have a look yet.
I was at a gig over the weekend and a huge hangover mixed with a ruined back have kept me away.
I only assumed that the crank bolt had backed out somehow because I only put a new Honda pulley onto it a couple of years ago.
I'll post an update after I've had a chance to have a proper look.

89 UKDM BA4 4WS (resto job!) · Post by **wurlycorner** » Tue Dec 12, 2023 11:08 pm

Oh! You've already put a new pulley on it? Argh... That is sounding a bit unlikely that it would have delaminated already then, to be fair...

I am surprised about bolts backing off though. Really surprised.

TitzonToast · Post by **TitzonToast** » Wed Dec 13, 2023 9:42 pm

wurlycorner wrote: ↑
Tue Dec 12, 2023 11:08 pm
Oh! You've already put a new pulley on it? Argh... That is sounding a bit unlikely that it would have delaminated already then, to be fair...

I am surprised about bolts backing off though. Really surprised.

I couldn't agree more, after what I had to through last winter to get the timing gear off when I was giving it a bit of a refresh.

89 UKDM BA4 4WS (resto job!) · Post by **wurlycorner** » Thu Dec 14, 2023 10:29 am

Did you oil the crank pulley bolt correctly as per the service manual (it's very particular about where to oil/where not to oil it)?

Scott560 · Post by **Scott560** » Thu Dec 14, 2023 10:51 am

I have to admit to not even torqueing the lower pully bolt to its full tightness (manual has some ludicrously high figure my cheapy wrench wont go to). I did however clean and lubricate the bolt as per the manual.

Iain - didn't you say that the original pulley has a defect in the bonding? I know we have had 1 other user where the bolt had come loose but I don't recall any others (FreeRanjEgg - however his motegi kit lives on on my car thanks to lankysod!)

TitzonToast · Post by **TitzonToast** » Sat Dec 16, 2023 8:05 pm

No, I absolutely did not lubricate the bolt when I put everything back together.
Oh sheet!

89 UKDM BA4 4WS (resto job!) · Post by **wurlycorner** » Sun Dec 17, 2023 9:20 pm

Scott560 wrote: ↑
Thu Dec 14, 2023 10:51 am
I have to admit to not even torqueing the lower pully bolt to its full tightness (manual has some ludicrously high figure my cheapy wrench wont go to). I did however clean and lubricate the bolt as per the manual.

Ah, that might well have been the issue then. It is important to do it up tight enough, to spec!

Iain - didn't you say that the original pulley has a defect in the bonding?

On mine, yes - a manufacturing defect in the original bonding, visible after it had come apart. That doesn't mean all others will suffer from it, just happened to be the case on mine.