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Fri Nov 14, 2014 2:06 pm

I've run with BBTs "Okrasa" 33mm inlet valves in my slightly modified 36hp heads the last 2 years (around 15.000km)
The other day I noticed a problem. Just over the valve locks, valve stem material was moved upwards making a little edge, so much that the valves couldn't be taken out through the valve guides without a little grinding.
Anybody else experienced anything like this? I run stock valve springs, and the original exhaust valves don't have that problem.
I'm thinking about using Wolfsburg West "Okrasa" valves instead, or are they made same place?

Edge on valve stem.

Valve can't pass through valve guide.

Valve after grinding it, so it pass throug the valve guide.

Fri Nov 14, 2014 2:42 pm

Hi Peter.

Yes it has been seen before. There are two main reasons for this.
1. Valve float.
2. Relatively soft valves. There is a solution to the problem, which includes SS valves and different locks and retainers. But to us Europeians its a little costly.

So first thing is to check your valve spring tension.

T

Sat Nov 15, 2014 11:53 am

also make sure the keepers are gaped. there needs to be a gap between them so they grab the valve,not let ot float in the keepers. if it were mine i would put a different type of valve/keeper in it...but thats me.

Sun Nov 16, 2014 4:16 am

What type of valve keeper what you use?

I doubt it's valve as running with fewer rpm's with my current setup than I used to do. And I never had the problem before.

Sun Nov 16, 2014 12:19 pm

That is very common for any of the "IVAM" brand 36hp valves (that is what BBT sells), and as Mark said, the fix for that is to gap the keepers. Everything I send out on rebuilt heads has had the keepers done that way. There are better valves, WW sells a stainless hardened 33mm intake that they use in their dual port 36hp heads. I've been using an exhaust valve that has a hardened stem top. To gap the keepers it's as simple as having a belt sander........

Mon Nov 17, 2014 1:31 am

Mr. Motorhead wrote: That is very common for any of the "IVAM" brand 36hp valves (that is what BBT sells), and as Mark said, the fix for that is to gap the keepers. Everything I send out on rebuilt heads has had the keepers done that way. There are better valves, WW sells a stainless hardened 33mm intake that they use in their dual port 36hp heads. I've been using an exhaust valve that has a hardened stem top. To gap the keepers it's as simple as having a belt sander........

Thanks! I´m not sure that I understand what IVAM stands for?
Sounds like I will buy the the WW valves and then pay alot of attention to that the keepers have a gap when I put it all together.

Mon Nov 17, 2014 9:27 am

IVAM is the brand of the valve.

Mon Nov 17, 2014 9:38 am

Mr. Motorhead wrote: IVAM is the brand of the valve.

Thank you.

Wed Nov 19, 2014 12:52 pm

The BBT Okrasa valves I got is made of Stainless Steel (non magnetic)

Wed Nov 19, 2014 1:06 pm

After closer inspection it turned out that the valve stem is 3/10mm thinner than original valves were the keepers are located, so therefor there aren't any gap between the keepers.

Wed Nov 19, 2014 1:55 pm

Peter: are your valves magnetic?

The stainless steel ones from IVAM "should" be of the same material composition as the WW.

Wed Nov 19, 2014 2:28 pm

tobiasax wrote: Peter: are your valves magnetic?

The stainless steel ones from IVAM "should" be of the same material composition as the WW.

Just returned from my garage so I can't check them now.
But I think they will work fine if only the keeper gap is there.

Thu Nov 20, 2014 3:27 am

Mr. Motorhead wrote: That is very common for any of the "IVAM" brand 36hp valves (that is what BBT sells), and as Mark said, the fix for that is to gap the keepers. Everything I send out on rebuilt heads has had the keepers done that way. There are better valves, WW sells a stainless hardened 33mm intake that they use in their dual port 36hp heads. I've been using an exhaust valve that has a hardened stem top. To gap the keepers it's as simple as having a belt sander........

As I got worried I asked Danne who did help me with the heads. He did claim that VW-type keepers are made to let the valve rotate and that you shouldn't gap them. In some (non-VW) applications the valve should not rotate, but then the keepers are not rotational symmetric. He wasn't sure how the case was with the 30/36hp VW ones (anyone who has facts on the subject?).

As for the material, according to IVAM material spec their non-magnetic valves (as BBT sell nowadays) "should" have the same material specs as the WW.

Thu Nov 20, 2014 8:00 am

tobiasax wrote: Mr. Motorhead wrote: That is very common for any of the "IVAM" brand 36hp valves (that is what BBT sells), and as Mark said, the fix for that is to gap the keepers. Everything I send out on rebuilt heads has had the keepers done that way. There are better valves, WW sells a stainless hardened 33mm intake that they use in their dual port 36hp heads. I've been using an exhaust valve that has a hardened stem top. To gap the keepers it's as simple as having a belt sander........

As I got worried I asked Danne who did help me with the heads. He did claim that VW-type keepers are made to let the valve rotate and that you shouldn't gap them. In some (non-VW) applications the valve should not rotate, but then the keepers are not rotational symmetric. He wasn't sure how the case was with the 30/36hp VW ones (anyone who has facts on the subject?).

As for the material, according to IVAM material spec their non-magnetic valves (as BBT sell nowadays) "should" have the same material specs as the WW.

I'm sure they are ment to rotate, that's why the adjusting screw is set a little of center on the valve stem, to turn the valve a little every time it pushes it down.