Bolt as removed from timing belt cover. Note the threads are choked up with something. Little did I know.....

Same bolt cleaned up with rotary brush. Note threads are now clear of debris.

Hi All, got an MY99 Impreza and am endeavouring to remove timing belt cover in order to change belt. I've no idea if it's ever been changed before, well, the cover bolts are very rusty but the upper ones I've managed to remove, apart from the one behind the pulley, only managing to snap one that screws into a captive nut... and the lower bolts are all much more corroded, and I removed this one today, but the threads in the aluminium backplate came out with the bolt! See upper pic. Anyway, I feel all this could have been avoided if only the bolts were lubed before fitting. Simple as that. So I just want to say before it's too late, when you've got a spare moment, why not remove the bolts in your timing cases and apply some copperslip or grease to the bolts so that when the time comes for belt change, you'll have fewer hassles. Still got 4 lower bolts to try to remove... Bliss!
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Sorry mate are you saying the timming cover bolts need checking and cleaning.

Is it not enough to check it at cam belt change or is that when you saw it

 

Hi, it looks like those bolts are in a fairly exposed position, and maybe the combination of steel into aluminium and the exposed position they're in they could do with a bit of protection in the way of lube on the threads and shoulders so when you want to remove them a few years down the line, you won't experience stripped threads or snapped bolts like I'm enjoying (not)

 

There isn't a lot of space there either. Good luck getting the stripped bolts out

 

I suspect a tap the next size up and some fresh bolts will be your friend here more than trying to get a drill in, unless you've got a 90 degree head and a short drill bit.

This is why I like working on my own car; once you've been through everything once all the bolts will be well put together so they actually come out next time! Anti seize and marine grease are wonderful creations...

 

its about £10 for a whole new set of nice shiny new bolts so why would you even bother cleaning up the old ones lol

 

Slightly missed my point there!.... OK, fit shiny new ones, BUT lube them 1st!.. then several years down the line, when you've a need to remove them, (they won't be shiny and new then) you won't have this hassle of stripped threads and snapped bolts. OR lube the old ones while you can still get 'em out before they deteriorate... just saying....

 

I'm thinking more in terms of a longer m6 bolt and a nut on the other end to reduce the amount of drilling needed. I'll use stainless ones!

 

Ah, if you can do that then yeah, definitely easier. I thought they were going into blank holes (I've only had the timing cover off once).

 

have done loads now and never stripped a thread so I think you have just been unlucky really ,, and I always copper slip my nuts and bolts

 

I love to cover my nuts in grease aswell 🤣

 

It doesn't appear to be an unusual occurrence! When my 1st bolt snapped (one on the lhs small cover) that screws into a captive nut in the plastic rear panel, I googled what to do, and found I wasn't alone!... A few on this forum and the NASIOC forum too, where it seems some owners had reverted to cable ties and/or Gorilla tape to secure the covers on. So it seems to be a trend, hardly surprising as those bolts are in an exposed position; facing, as they do, the direction of travel.

 

yeah most of the time I soak the bolts overnight with tons of WD40 ,, the captive nuts go all the time I was more talking about the threads in the block ,, another thing I tend to do is try them when the engine is still warm and everything is expanded ,, but more do it when cold lol

 

That's not a bad idea! I'll try that out tomorrow (warming the engine first)

 

Domino64,.. Hope this isn't thread creep, but while on the subject of cam cover, can you recommend a good way to remove the crank pulley to get to the cam cover bolt behind it? Also is it recommended to use a new crank pulley bolt...? Ta!

 

locking tool is prob the best way to do it,,, although if stuck iv had friends put it in gear and hold the brakes on to undo it lol ,, I made my own tool with a hole in the centre to undo it ,, old bolt should be fine but always check the threads just in case

 

Oh yeah, some of the holes are blind, and some aren't. Fortunately for me, the stripped thread is in a non-blind hole, so I can fit a longer bolt + a lock nut. Incidentally, I got the engine hot + used a hotair gun and managed to remove the rest of them OK... apart from the one behind the crank pulley as not got around to removing that yet.
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