Valve guide

[ekacpuc]

Just fact checking..

I have a low miles set of tims stage 2 heads. I messed up a valve guide pulling a lash cap off (anger, vice grips and a hammer are a bad mix). I contacted a machinist about what would be required to correct it. He informed me he’d replace the guides and I didn’t need to send the valves in to him.

Now as a kid I’ve done valve guides before and just lapped new valves in. I didn’t care about performance. I’ve read that the proper way would be to replace the guides, then adjust the seats checking the new valves to make them line up (centered and depth).

So I’m wondering if since the seats are still good if there’s no need to mess with them.. heck if that’s the case I’ll just replace my own guides and check where the seats hit on the valves (they’re new)...

[66brm]

Valve seat cutting/ grinding is done using the guide as a "guide" for where the valve will sit when closed. How is the machinist going to size or ream the guide to the correct clearance if they don't have the valve in hand to measure? The valve seat contact will need to be at the very least lapped if not recut to get a good seal
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Aust. RHD 66 Type 1
Aust. RHD 57 Type 1 Oval

[ekacpuc]

[Dan Ruddock]

I would just replace the one guide. If it isn't broke don't fix it. You must cut the seat for every guide you replace. Is it a intake or exhaust guide? On heads cut for dual springs you have to be very careful if it is a intake guide, very easy to crack the guide boss. I like to use a coring drill for removal, berg has them. Heat head and chill guide when you install. Like to see a pic of the damaged guide. Dan

https://www.thesamba.com/vw/classifieds/detail.php?id=1007833

[66brm]

Agreed, I would just do the one, otherwise you may end up with more issues
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Aust. RHD 66 Type 1
Aust. RHD 57 Type 1 Oval

[Alstrup]

What Dan said.
If the heads are cut for dual valve springs, which I assume they are, I would repair the giude with a K line insert unless the guide is totally molested.
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https://www.thesamba.com/vw/forum/viewtopic.php?t=435993

[Dan Ruddock]

[mark tucker]

how is it effed up?

[74 Thing]

Post some photos

[ekacpuc]

Doing one sounds wise. The rest feel good. It’s exhaust.

I was gonna core it but I’ll look into the liner

You can see it’s just a bit out of round in bottom pic at top guide towards right. The valve wiggles more than it should. It doesn’t look out of round in the exhaust port end. Valve wiggles more than it should though.

I prob shoulda got a puller.. I had empi caps mostly. I bought CB and empi at same time. Figured the CB was too tight and went to use the empi ones but I lost two empi so I used the CB against my best judgment for the two..

[ekacpuc]

[ekacpuc]

[Alstrup]

https://www.pommee.nl/webshop/contents/en-uk/p782.html
Any decent engine repair shop should have these. Question is whether they have them in 8 mm. But 5/16" will work too if you have the tools to ream it up to correct size.
The diamond flex hone is the one you want. http://www.brushresearch.com/brushes.php?c1=1
Remember to clean the guide thoroughly after the flex hone, or the small abrasive residue will wear the guide out in no time flat.
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https://www.thesamba.com/vw/forum/viewtopic.php?t=435993

[ekacpuc]

[frenchroast]

[ekacpuc]

[RWK]

Easy way to get guide out is to drill it out from the rocker side just a little larger then 3/8 but don't go all the way thru, stop 3/8- 1/2 from chamber side, tap the guide on that side for 3/8-16 and screw in a bolt, then from rocker side drive guide out by putting a punch on the bolt you screwed into the guide. May have to drill larger to the boss on the rocker side to get head off guide. You won't damage head boss this way.
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73 Type 181
63 Type 113
63 Type 261- 428 071
62 Type 241-378 025 178 530

[Dan Ruddock]

The Berg coring drill is the best way to go. I have had mine for 30 years and has paid for itself many times. Can be re-sharpened, drills out enough of the guide for easy removal, does not walk off center and drill into the head, maintains the guide holes original size and shape. Cheap insurance to not screw it up. Good that it is the exhaust, if the boss is damaged you can just put in one of those dummy bosses which will fit my beehives. On the exhaust side there is plenty to hold the guide in place even if the boss is damaged, no need to weld it up. That is not to say go ahead screw it up, just be careful to keep the head as original as possible.

Dan

[[email protected]]

You guys all realize that the head is cut for dual springs, right? Depending on how thin the guide boss is, putting in an larger OD guide will most likely crack that. What does he do then? Run over to the guide boss store and then pick up a cutter for dual springs from Ace?

Also, if one guide comes loose, my philosophy is to replace EVERY guide. Why? Because the future cost of NOT doing that, having another guide come loose and then grenade the engine is VERY high compared to changing guides now.

Sure, it may be just fine replacing one and the engine may run for hundreds of thousands of worry free miles.....but what if it doesn't?
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Cylinder Head Reference Sheet

[mark tucker]

I will not use tight lash caps. Ive never seen a set of heads that had them that they did not fuck something up..... as for the looses ones being too loose for your likeing.... have ytou ever seen the oe fors lashcaps on the old small blocks??? the stems are 11/32"( .341) the end of the stem is machined down to probably 7 mm( .276") the lash cap fits like it's almost .020" too loose... and they work just fine. Ive taken 3/8" lash caps and bushed them down to 11/32" to use on my personal engine because.....my last set 11/32" lashcaps went on SOMEBODY ELSE's ENGINE!!! and I had lots of manley 3/8" lashcaps in stock. I never had any issue with them.