Is my rotary valve toast?

[ashby]

In the process of installing a SBT engine in my 96 GTi. Around 300-320 hours on it. At first look I figured the rotory valve and plate needed to be replaced but I figured I'd get a second opinion. It's not scored or dented or gouged, just what I would call typical wear, but I'm not sure what these are supposed to look like either.

 

[mikidymac]

Te cover actually looks good. It has some wear but you can still see the factory machine marks running up and down. The rotary valve itself looks pretty worn so you might consider replacing it.

 

[CReynoldsMIZ]

Is there a groove on the edge of the machined surface at the bottom? like where its has worn down and left a small high spot? if so, might just wanna replace. doesn't look terrible though

 

[pwgsx]

id be more worried about those old oil injection lines

 

[Sportster-2001-951C-Stock]

Valve looks rough to me too, I think the service manual gives clearance spec for both used and new valves, or not? Reman is available I believe.

Be careful you get the correct ones, there are several I believe (snowmobile guys run different ones).

 

[mikidymac]

I would advise against the WSM ones as they are not splined the same as OEM. Not sure on the SBT ones.

 

[nitr0genics]

Valve looks rough to me too, I think the service manual gives clearance spec for both used and new valves, or not? Reman is available I believe.

Be careful you get the correct ones, there are several I believe (snowmobile guys run different ones).

As long as its within tolerance its fine (new or used), spec is 0.30mm ± 0.05mm (.012" ± .002") - below 0.25mm can create overheating above 0.35mm can create hard starting issues, check clearance by installing rotary valve cover WITHOUT o-ring and torque to 20lb/ft then using feeler gauge between valve and cover check clearance

if you get the cover skimmed (milled) the seating surface of the o-ring groove must also be milled to be 1.0mm ± 0.03mm (.039" ± .001") deep

the crank side surface looks fine as other have said but if needs be these can also be reworked I believe

As for the correct rotary valve it should be a 159° valve timed to 146.5° (I've just done my 787)

 

[ashby]

id be more worried about those old oil injection lines

They are getting replaced with this new motor.

Thanks for the replies! I'll see about checking it for clearance.

 

[ashby]

I checked the clearance and I'm right between .011 and .012. I believe that's ok.

Now if I can figure out how to get a tach/hour meter installed on this thing I'll be set.

 

[Spimothy Leary]

I checked the clearance and I'm right between .011 and .012. I believe that's ok.

Now if I can figure out how to get a tach/hour meter installed on this thing I'll be set.

tto tach's are pretty popular on this forum, and very very easy to install, actually within MY abilities, and i'm barely capable of coloring between the lines.

cheap and easy ebay purchase.

http://www.ebay.com/itm/Trail-Tech-...ash=item2c6d3e07a7:g:rNwAAOSwstxVDIKm&vxp=mtr

 

[nitr0genics]

doesn't get much simpler!

 

[ashby]

Sweet thanks..I have been lightly searching but was getting mixed reviews and mostly lawn mower type hour meters. Want to be able to keep up with the hours on this new engine. Thanks for the TT link I'll buy that if it is recommended.