In theory you can fit it dry, but I used Blue Hylomar (very thin coat) to locate the gasket onto the pump. And left the engine facing side dry. That means that next time I don't need to have to scrape sealant off the block.

I also found the locating pegs on the block were a very tight fit into the holes of the pump. As I didn't want to be tightening bolts just to pull the pump onto the pegs, I increased the holes in the pump slighly.

I did several dry fit runs just to make sure it all would go back easily.

 

+ 1 to what John said.
If you put some sealant, put a thin coat only on the pump side. Easier on your next water pump change.
With the right gasket, you should not need any sealant.

You should have a sealing ring on the drain plugs.

 

Clean and dry works fine for me. Or as John suggests, a little Hylomar film on the pump-side only if you must.

PTFE tape works great on tapered pipe threads, not so hot on the straight threads of the block galley plugs.

My theory is that there's actually one "thread" winding its way around the bolt. When installed, there's pressure on the outer face of that thread, leaving a gap at the back of the thread where coolant can pass. It takes just a dab of PTFE paste to block that passage at the rear. At the same ime, folks have discovered that the steel plugs have grown in the aluminum or the aluminum has corroded and swelled into the bolt. Regardless, coating the whole bolt with PTFE paste offers a chance to leave a barrier layer between the two dissimilar metals in addition to limiting the possible leakage through the thread. You could use anti-sieze on the plugs and get a similar effect I suspect. Like any lubricated thread, you'll want to adjust the tightening torque down. My 15 lbs/ft suggestion considers the lubrication, and is successfully battle-tested. Plugs come out easily every year or two for coolant changes, and don't leak or fall out.

 

Off-hand, I can't think of any place on a vehicle that I would use Teflon tape.

Strong support for the Teflon paste.

 

Wally,
There is one place where I have successfully used teflon tape on my 928's. I wrap it around the front sway bar where it contacts the polyurethane bushings (not OE bushings). Keeps the squeaks out. But, due to it's flow characteristics, I usually replace it annually!

Gary-

 

For the bolts it might be useful to use PTFE tape on the shoulder but pointless on the parallel threads which probably do well with anti seize type grease I would think.

Another thing I noticed is that when I pulled the piston out of the tensioner once belt was off [i.e. tensioner bolt wound fully out] no oil came out. Is this normal or does it mean the oil has leaked out of the tensioner and it needs a good r/r?

Regards

Fred

 

Remove/restore time! Mainly new O-rings, gasket and oil.

 

The boot on my tensioner is always crispy and cracked when I change the belt. Guessing that the oil charge "dissipates" there. I followed Stan's guidance and put STP Oil Treatment in mine a few weeks ago when the tension light came on. I have it adjusted at the middle of the Kempf scale, so running low on oil in the tensioner pops the light. This time it wasn't enough, plus it's due for a belt and tensioner refit based on age anyway. Another weekend duty to line up!

 

Attachment 812980Wally,

Pretty much figured that one- already got the parts lined up just deciding whether to go this route or splash out a bit more green stuff and go for Ken's PK tensioner. Love the other bits I have from clever Ken. Withouth wishing to risk starting WW3 or trigger an invasion of Ukraine, now that it has been out a few years and I have not picked up any negative vibes, it seems it might be a worthwhile consideration when they are back in stock. Any thoughts?



Also, I noticed that my cam wheels are a tad "shiny" on the top surfaces. I cannot see any signs of chronic indentation so if the PKT runs with less tension presumably that can only be a good thing in terms of wear or at least arresting such/eeking out longer life to replacement? A couple of pictures to demonstrate the situation- any comments?

Also attach a photo of the failed pump and the label showing it was re-manufactured- considering that pump has been in the motor for quite a number of years not bad at all really- I purchased this unit from Devek although cannot remember when it was installed- I am guessing about 8 years ago and about 60k km as I think about it.

Finally your truly with removed timing belt and hyper toy in the background.

Apologies that I cannot arrrange text and pictures better- have not figured that one out yet.

Regards

Fred

 

Thats a strange wear pattern on the 5-8 cam gear - are you sure there was a whole cambelt on there when you removed it. Looks to me like it ran on 2/3 of a belt for some time ?

 

Jon,

I thougt it may be a bit of an optical illusion as the polished surface looks quite even across the contact patch of the belt when you see it- there are signs of wear with a flat square and this alarm me a little. Not sure what is going on or why. These gears have seen about 150k km during their life to date. The oil pump and crank pinions superficially look OK but...? Not sure at all what is going on.

Belt tension checked out OK during previous checks and before removal and the belt looks in pristine condition- but that has only done about 30k km in about 6 years.

Another query for anyone reading- I have just had the tensioner off and everything looks in good nick inside- a little bit of particulate matter but if there was a problem I would say it was the gasket that looked in poor conditions.

Question: I do not have a gasket at the moment- if I seal the tensioner body with Blue RTV will the slightly closer fit effect how the plunger engages the tensioner socket? Obviously one does not want to induce a lateral load when it engages or the tensioner will not work correctly. I do not think it is a problem and there seems to be some lateral give in the system anyway. Indeed re-reading Dwayne's write up suggests it can be done with the likes of TRV.

Regards

Fred

 

Fred,

I don't have a stock tensioner right now, and never worked on one either.
I have the PK tensioner and happy with it. Good product (I think) and easy to install.

Looking at both gears, I would change them. There's not much life left on those. When the coating start to wear - like yours, it goes fast after.
I know there not cheap but it would be the perfect time to do it. And go with a PK tensioner if you want.

That's what I would do. But that's me!

 

Fred, from your picture it looks you've worn through the anodizing already. Guidance on gears needs to consider whether they will be ok for another 50k,not just whether they are ok now. Considering your dust-free driving environment, consider that wear factor and life expectation. Then put we gears in your Care Package request.

Your tensioner boot has, um, relieved itself already, ventilating the tensioner. I'm thi king there must be a better boot option, maybe a drum brake wheel cylinder boot from a truck. They might be better with the heat.

 

Bob,

I am thinking the cam gear has gone but I am surprised it has gone like it has- what is a typical life for a cam gear?

I have a trick up my sleeve-I think I know where I may be able to get a cam wheel from- I have a spare one upstairs in good nick and I know where there is a TBF'd motor..

The tensioner surprised me- I was a little confiused about how it works and the external piston coming out does not cause the oil to come out. Inside everything was very clean and there were no signs of oil getting past the seal into the adjustment bolt area or into the front boot area. Even the front boot was in good pliable condition which surprised me somewhat. The spring washers were a touch brown in colour- did not look like rust- everything seemed very clean inside- I have seen those washers looking black!

Still a little confused about how the electrical circuit for the warning light works if anyone can explain that- I must be a bit dumb today!

Regards

Fred

 

Fred,

The washers have a BC coating on them to reduce friction and corrosion, hence the colors. The oil usually sits below the piston, cycles up next to it to the o-ring area. Some leaks by depending on seal quality. In theory the boot is for dust protection only, but I've seen oil in the top in several cars.

There's a little check valve in the bottom of the piston that meters oil past in the compression direction, let's it flow more freely on extension. This is for later tensioners, for those playing along at home. I put the gasket on dry, but may add a thin bit of Hylomar this time to try and keep the oil in longer. Same Hylomar on the bolts that pass to the coolant galley, btw. Otherwise anti-seize.

There are a couple places referenced in the US that will recoat the can gears. Perhaps somewhere near you there's a similar service. I'll probably get new gears this time at about 110k on the meter, and send my old ones for recoating then into the spares bin. Look carefully at the crank and oil pump gears. If the wear on the can gears was caused by debris/sand/dust, the steel gears will show similar wear. The original anodizing on the came gears is almost as tough as the steel gears, but the load is more concentrated on the smaller pieces.

The electrical part has who contacts separated by the spring. One contact is ground, the other goes to the pigtail to the pass through connector in the cover. Belt tension compresses the spring, letting the contacts touch. The spring rate of the washers is steep, so a small movement will let the contacts separate, activating the warning system. Simple yet effective with this type of spring, one of the reasons why it can't be used with Ken's tensioner.