VR6 top timing chain tensioner bolt

[Roger Blassberg 0]

I changed the whole set of chains, tensioners and guide rails about 20,000 miles ago using the latest top pad and tensioner bolt, using genuine parts. Now the chain(s) are, rather disappointingly, rattling again so I will replace the top tensioner bolt as a first move before the (inevitable, probably) strip down to inspect the top pad and guide rail.

The question is, do I need to prime the bolt with oil before putting it in, or is the spring sufficient to pre-load the tensioner pad until oil pressure comes up? I will take out the plugs and the fuel pump relay and give the engine a good spin before firing it up anyway to ensure full oil pressure in the new bolt.

 

Best wishes

 

RB

[Jim Bowen 1]

I once started to blame my mk4 bolt and tensioner for the noise, couldn't think of anything else. Have been considering going back to original stuff. In fact i've found most of the mods i've done end up getting swapped back to original stuff.

 

The bolt looked quite a bit different to the original iirc

[fla 9]

Roger - i've got a spare (new) tensioner bolt if you want to try it out first to confirm you need it. I primed it first when doing my chains, but then as you mention, spun the engine over without sparkplugs or fuel to build up the tension via the oil circuit.

[DriverVR6 11]

I'm about to do the chains/tensioners/chain guides on mine. I've been trying to decide if I should just stick with the original 2 piece rivetted pad tensioner and "older style" tensioner bolt, or if I should go for the "updated" mk4 one piece tensioner and "newer" tensioner bolt.

 

Has anyone else had experience with both systems? Pros and cons would be helpful.

[Jim Bowen 1]

I was going to get old style stuff. I figured the top bits aren't too hard to change and the original stuff lasted nearly 200k

[Roger Chatfield 0]

I don't really have much experience of Corrado's but I recently found this in my oil pump stainer.

 

 

It's the top of an old style tensioner, mine was changed for the new style a couple of years ago when the chains were renewed so that has been been 'floating' about for awhile.

 

Personally, I'd upgrade to the newer style all plastic item, I think they are something like 13 quid.

 

Rog.

[Roger Blassberg 0]

Hasan,

thanks for the offer, but I have now bought the new bolt. I'll give it a go; how did you prime it? Immerse in a pot of oil and push the plunger in and out a few times?

RB

[Kevin Bacon 5]

Roger, VW had a dodgy batch of tensioners. If you buy a replacement now it should be the latest version. There is no way the chain gear will be worn out after 20K. If you do take the upper cover off, check the plastic guide rail as they are prone to breaking.

 

Don't need to prime the later bolts. The internal spring prevents tooth skipping on initial startup but if it's a concern, remove the plugs and disconnect the crank sensor, then crank it over for at least 45 seconds.

[Roger Blassberg 0]

I changed the tensioner yesterday and it is VERY much quieter, but not totally rattle-free. I'm probably being ultra-critical of a very "mature" engine. I'll have a look at the top guide rail some time soon, but I am confident that there is no impending catastrophe (famous last words..........)

Thanks to all who commented.

 

RB