Topic: Rusted stuck valve

[Rudi91]

Hi guys,

I've got a problem with the valves on my CB350F '73.
I've taken 7 out without a problem. 6 of em just slide right out and 1 I had to tap out with some wood and a hammer (just 1 tap was enough).
I've only got one left to take out but it just won't budge at all.
What I've tried so far;
Loosening it with WD-40.
Motip shock oil.
Pounding it out with some wood(so I won't damage the valve) and a hammer.
Trying to pull it out with my bare hands.

I'm at my wit's end here, does anyone know of a magical spray or something to get it loose?

The troublemaker:


PS: I'd like to use this cylinder head on my running engine cause one of the sparkplug holes is cross threaded. And I can restore this head without disabling my Honda 
I'll beadblast the valves and cylinder head when I get this valve out.

[Kenzo1979]

Try saturating in PB Blaster for a day.  Also, try carefully heating it up and tapping it loose.

[tool14]

Make sure tip is not mushroomed,to go thru valve guide.

[Vinhead1957]

You can have the plug helicoiled also !   But the stuck valve use some heat also.  Instead of propane use mapp gas.   Then tap with block of wood and hammer.  Center the heat around the guide.

[Rudi91]

Thanks for the tips, guys.
The product u named aren't available over here (The Netherlands) as far as I know. But I'll get some similar products.

I'd prefer not too helicoil the thread cause I don't have the tools for it and I've never done that. Plus the head im working on right now (with the stuck valve) is the original one and it's an heirloom so I'd like to use as much of it as possible.

[lone*X]

Dry Ice on the valve to shrink it, break the bond.

[dave500]

is it actually rusted?does it move from closed to open then bind?there probably is a burr on the valve tip,file it off and itll come through,the one you forced through will have scored the guide.

[camelman]

I second Dave's comment.  The valve end is mushroomed.  You'll scratch your valve guide if you force it out.  Push it back into place and use emory cloth or a light file to smooth off the end of the valve.  It'll slip out easily after you do that.

[kghost]

Just for future reference.......wd40 is not really designed to free rusted stuff.

It was made to displace water.

Any commercial product designed for rusted fasteners will work better.

If you don't have any MEK or acetone mixed with transmission or hydraulic fluid will do the trick. About 50/50 does the trick.

The MEK/acetone wicks the lube down through.

[dusterdude]

Pb blaster

[iron_worker]

As others have said ... the valve tip is probably mushroomed from improperly set valve lash. You need to grind or file down the burr that is there. You probably have already scored the guide.

IW

[Rudi91]

Thanks alot for the tips guys.
Didn't have any of the stuff at home and I didn't get home before the shop closed therefor I haven't had the chance too try it out yet.
Did make a pic of the valve tip though :


There is a little chunck out of it but its not mushroomed nor does it has any burr, correct me if i'm wrong.

EDIT: This is also the position it's stuck in btw.

[dave500]

ok so its stuck,not free at all?in that case youll have to belt it out and replace the guide if its rusted.