VR6 head questions

[MarkGolf 0]

Im building up my spare head..

 

When pullling a valve up and down from the bottom of the head, should it be quite tight?

 

How do I change a valve oil seal as one of them is broken and if needs be, how do I change a guide?

 

How much are the seals and the guides?

 

Thanks!

[Kevin Bacon 5]

It should move up and down smoothly with no resistance. With the valve about a cm proud of the port, rock it, there should be very very little lateral movement. Also check the guides for ovalisation.

 

Guides need to be pressed out/in in a machine shop. You can do them yourself with a precisely turned drift tool and a hammer, but personally I'd take it a machine shop as you need to know the precise insertion dimensions.

 

Seals are easy. Pull the old ones off with pliers. New ones come with a plastic sleeve. Slide them over the guides leaving the sleeve on. Oil the valve stems liberally and only when the valve is slid through the guide and seal should you remove the plastic sleeve from the seal.

 

Guides are about £6 each from VW, seals are about £1 each but if you buy a head set, the seals come with it. Guides don't though.

[MarkGolf 0]

Nice one Kev!

 

Luckily, I have no lateral movement, but do find the valves quite stiff going up and down, maybe because the valves had just been cleaned with parafin.. Not sure if a quick oil will solve the prob?

 

In this pic, what is contained in the small bag?

 

http://i6.ebayimg.com/02/i/03/a8/5c/76_1_b.JPG

 

They seat in the block?

[Kevin Bacon 5]

Yeah the little bag in the middle is your seals. Looks to be a good head set, is it a genuine Victor Reinz one? If not, VAG do nice fit and forget metal head gaskets for the VR now.

 

The valve shouldn't be stiff in the guide really, but it depends on your definition of stiff....ooo er. It won't slide in and out loosely, again ooo er missus, but it shouldn't bind. It's a tight fit (gotta stop this, LOL!) for sure though. Check your valve stems for deep scoring marks which can causing binding, but don't forget they work against the spring, so any stiffness is academical as the spring is stronger than what you can push by hand if you get my drift?

 

Sounds like you're OK, try some oil and try again. They might bind if dry but the guides are sintered bronze, which is a lubricant in itself against the hardended steel valve.

 

What they should feel like is the moving the chain tensioning bolt piston in and out if you've ever done that? I.e. not sloppy loose, but feels like you're pulling against a suction...... ah poo, it's hard to explain....but if there's no lateral movement, you're good to go :thumb right:

[samm_cvr6 0]

I'm actually changing valv seals,guides,stretch bolts and gaskets at the moment, a friend of mine will be doing the rest tho as I haven't done this before, I have some pics. Check the post I put up.

[MarkGolf 0]

Nice one!!

 

Im just building this head as a backup head as Im probably going to send my current head off to be 'played with' sometime next year...

There's a light scoring on the valves, but defo no lip what so ever! The movement is like a suction movement from the other end, so it all sounds good! :D

 

Lets stop this talking about the stiffness...lol

 

 

Im sure those seal have lil springs around them or somehitng (i cud be imagining things), then there are these clear 'tube' things which I have no idea where they go!

 

Does anyone have pics of a head which has been freshly times so i can see the position of the cams

 

 

Thanks!

[samm_cvr6 0]

The cams have 7 different numbers on them, I think it is something to do with the precision engineering of them, and another really cool thing is, if you look at the cams, they have mini VW and audi rings logos on them!

You doing all this work yourself?