Lash caps, has anyone tried this on M20 or M10/30?

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H35-24
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Post Mon Aug 06, 2012 7:10 pm

I have a exhaustvalve on my daily driver, that has become to short for the ecxentric. Thus I has started wearing more and more, and as I can't adjust the clearence the wear seems to accelerate more rapidly.

I have found out that Volvo, VW bug's and some American cars use these small "top hats" on the valves exactly to avoid my situation.

So I'm VERY keen on getting a Lash cap that could shut my valve up, and keep me from having to remove the hole cylinderhead.

Has anyone tried Lashcaps?

Here is a link to some lashcaps for a VW bug:

http://vwparts.aircooled.net/Hardened-L ... p/4029.htm
Why is there not enough time to do it right, but allways enough time to fix the errors - I borrowed that, just so reallistic in my line of work.
pacerpete
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Post Mon Aug 06, 2012 8:07 pm

I have some M10/20/30 oversize rocker eccentrics, if these dont fix it, you are in trouble ! £10 + post each.
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Post Mon Aug 06, 2012 10:04 pm

pacerpete wrote:I have some M10/20/30 oversize rocker eccentrics, if these dont fix it, you are in trouble ! £10 + post each.
Don't know how much the wear is right now. I tried taking a standard excentric and adding material by welding it on, and then grinding it back to the propper shape. It does the job a tickover, but once I rev it it starts again, I think, this is because the welded material is too soft.

Anyway since I'm that far, I worried that oversize eccentrics might only be a temperary fix, as the wear on the valve will continue.

How much oversize are the eccentrics you got?
Why is there not enough time to do it right, but allways enough time to fix the errors - I borrowed that, just so reallistic in my line of work.
HairyScreech
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Post Tue Aug 07, 2012 2:29 pm

Actually it might be the other way around. Are the valves bi metal or tip hardened? If they are tip hardened then it may have worn through and the rough surface from grinding the eccentric may have quickly filed through the valve stem.

If so then a lash cap could save the day, as they would proven the valve disappearing.
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Post Tue Aug 07, 2012 6:56 pm

HairyScreech wrote:Actually it might be the other way around. Are the valves bi metal or tip hardened? If they are tip hardened then it may have worn through and the rough surface from grinding the eccentric may have quickly filed through the valve stem.

If so then a lash cap could save the day, as they would proven the valve disappearing.
I'll agree, but the initial wear that has started the problem I'm a bit clueless about. I noticed when I bought the car with 127 tkm (80.000 miles) it already had a FEBI cam, so something has been troubling the valvetrain at an early stage.
Why is there not enough time to do it right, but allways enough time to fix the errors - I borrowed that, just so reallistic in my line of work.
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reggid
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Post Wed Aug 08, 2012 3:18 am

bmp design in the USA sell lash caps for the M20 and oversized eccentric as well. VAC motorpsort also sell lash caps
E30 325is with M20B31
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Post Thu Aug 09, 2012 8:28 pm

reggid wrote:bmp design in the USA sell lash caps for the M20 and oversized eccentric as well. VAC motorpsort also sell lash caps
Hi Reggid

Yes I have found them:

http://store.vacmotorsports.com/vac---7 ... p1678.aspx

Asked CA international, VAC's UK dealer if they could send me some. Lets see what happens.
Why is there not enough time to do it right, but allways enough time to fix the errors - I borrowed that, just so reallistic in my line of work.
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Post Sun Aug 12, 2012 4:39 am

Topped lubrication failure at some point in the cars life a possibility?
2.8 development thread http://www.e30zone.net/modules.php?name ... c&t=170822

m3.3.1 m20 thread - now running, chip needed - any volunteers?
http://www.e30zone.net/modules.php?name ... =viewtopic&
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Post Mon Aug 13, 2012 7:16 pm

It seems that if you get to the lash cap propaganda there are 2 arguments:

1: wear on standard valves, like mine
2:tuning with special valves that can't take the punishment, titanium, and some stainless.
Why is there not enough time to do it right, but allways enough time to fix the errors - I borrowed that, just so reallistic in my line of work.