Guide rail pin nightmare!

[TrevorC]

Busy replacing the timing chain tensioner and guide rails on the 450slc and can't believe my bad luck!

Four of the guide rail pins came out beautifully, but I stripped the thread on the 5th. After trying all sorts of tricks to get the pin out, I bought a 6mm "recoil" kit, drilled, tapped and coiled the pin and managed to extract it and breathe a sigh of relief!

But, as luck would have it, the 6th pin has NO thread, as in ZERO! Must have been a dud from the factory. I wish I could have a word or two with the guy who assembled this engine! Surely he would have noticed that the pin had no thread when he tapped it in? Anyway, so now I have to tap a thread in this pin as well. Wish me luck!

[meltedpanda]

ugh , possibly the threads have worn away and were there at one time??

[Walrus]

Originally Posted by meltedpanda

ugh , possibly the threads have worn away and were there at one time??

What would wear them?

[TrevorC]

Nope, definately no threads and the inner diameter of the pin is smaller than it would be if it was threaded. The photo is a bit blurry, but it's still pretty clear to see.

I'll tackle it this weekend, but I first need to figure out the best way of rotating the tap because space is limited there and my tap handle is too big. Fun!

[Walrus]

Originally Posted by TrevorC

Nope, definately no threads and the inner diameter of the pin is smaller than it would be if it was threaded. The photo is a bit blurry, but it's still pretty clear to see.

I'll tackle it this weekend, but I first need to figure out the best way of rotating the tap because space is limited there and my tap handle is too big. Fun!

Which pin is this? Its not the one in the tensioner, is it?

[meltedpanda]

could it have been an original press fit? then again , doubt that

[rs899]

Why don't you just buy another pin or find one at a junkyard? Seems to me your tapped one might be more likely to cause a new headache next time after all the trauma it has been through.

[rowdie]

Do you have a square socket the size of the tap end? You could use a ratchet. On some tap handles the cross bar can be removed and a 3/8 or 1/4 ratchet used.

[TrevorC]

I think I'll replace all the pins just to be safe. This one is not the tensioner rail, but the lower pin of the guide rail on the same side.

I don't have a square socket, but I'll try and use a normal hex socket - good idea.

[TrevorC]

OK, I found that I could remove the cross bars of my tap handle and used a short 8mm bolt in place of one of the bars to clamp the tap. That worked and the non-threaded pin is now out!

Now to order the replacement rails and pins and get it all back together again.