Thread: Timing belt change fail.

ouch.

Yeah, sometimes it's prudent to change bolts even though they can look perfectly fine.

Long bolts on Tdi waterpump can be like this.

Back in my RRC days when rubber bushes were the only real option, my panhard rod would flog out quite regularly(I used to do 90-100K klms a year)
I found after changing the bushes, the vibration in the stg would only be lessened, not always eliminated. bolts felt fine in the new bushes but that millimeter or so of play was the cause for the very slight vibe over rough roads.
Change the bolts and all fine again .. as fine as a old design could be.
So as a habit, changing the panhard bushes also meant new bolts too.

For a job such as engine internals .. when in doubt, don't be in doubt .. just change them.

According to the LR Freelander manual, you use the same crankshaft pulley bolt. That surprised me.

Originally Posted by Bohica

According to the LR Freelander manual, you use the same crankshaft pulley bolt. That surprised me.

If the crank is keyed then it wouldn't surprise me unlike the 2.7/3.0 TDV6 where there is no key so needs to be fecking tight hence not re-used.

Originally Posted by loanrangie

If the crank is keyed then it wouldn't surprise me unlike the 2.7/3.0 TDV6 where there is no key so needs to be fecking tight hence not re-used.

It is keyed. As for shearing the bolt! the cylinder block is I believe aluminum. So how do you shear a 155mm steel bolt that bolts into an aluminium casting!
I know I am just trying to find ways to absolve me of responsibility.

Originally Posted by Bohica

It is keyed. As for shearing the bolt! the cylinder block is I believe aluminum. So how do you shear a 155mm steel bolt that bolts into an aluminium casting!
I know I am just trying to find ways to absolve me of responsibility.

The bolt is a one use stretch bolt! It screws into the crankshaft, not the block. How tight did you do it up? Off the top of my head it’s something like 72Nm then a further 82°.

Man that sucks big time.

But are you talking about the idler pulley bolt or the crankshaft pulley bolt? I thought you first said the idler.

I can see how the idler could have fallen out if it wasn't done up enough (60Nm). The idler pulley bolt only bolts into the pulley itself and not the engine block. The idler pulley mount has a slot and not a hole where the bolt goes through and is located in the mount with the bearing shaft of the pulley. So if it did come loose the idler could have just dropped out of the slot and the bolt may sheared as the pulley was falling out and rattled around with the timing belt as your engine was shutting down.

The bolt on the idler pulley isn't a "Torque to Yield" bolt so I can't imagine how it would just have sheared in service if it wasn't over torqued. Cause really the bolt just holds the idler in place and there shouldn't be that much load on it.

So I hope your new engine is going well, but when is it due for timing belt?

Cheers Steve.

Originally Posted by Bohica

..... The idler pulley bolt had sheared off.
I know I did not do it up that tight!!
.....

Originally Posted by Badger51

The bolt is a one use stretch bolt! It screws into the crankshaft, not the block. How tight did you do it up? Off the top of my head it’s something like 72Nm then a further 82°.

Huh? .. idler pulley bolt into the crankshaft?

Me thinks you may have misread something in the original post.