[SEL] Reaming valve stem tower

[Curt]

Rick,
I just went out and surfed your New Way pictures again and see that the 
exhaust valve is directly under the intake valve. Understand I haven't 
fixed up Missy's New Way yet so I have no New Way experience to draw on. 
But the Baker Monitor is configured similarly, just reversed. On the BM 
the exhaust valve cage comes out and the intake is built into the head. 
My point is that when they were building your engine they likely 
machined the intake valve cage fit, reamed the exhaust valve stem, and 
cut the exhaust valve seat all in one set up. Therefore, to keep 
everything on center and aligned,  how about making a guide that fits in 
the intake cage cavity that will precisely guide the reamer you will be 
using to clean up the exhaust guide.
When I did Devin's engine I made a guide of brass that had a 45° taper 
on one end that wedged into the valve seat. The OD was also made to 
square up perfectly in the valve cage bore. I turned and reamed the 
brass guide in one setup so everything was dead concentric. I reamed the 
brass guide to assure a barely slip fit on the shank of the reamers. 
This kept the reamers running true. I had to open the guide up in 3 
steps with reamers to get 100% cleanup. All in all it took .062 increase 
in size. So what were 5/16" shanks on the valves are now 3/8".
Here is a picture of the fixture to guide the reamer:
<http://www.oldengine.org/members/holland/images/DevinsBakerMonitorRebuild/Intake2.jpg>
<http://www.oldengine.org/members/holland/images/DevinsBakerMonitorRebuild/Intake5.jpg>
and in use:
<http://www.oldengine.org/members/holland/images/DevinsBakerMonitorRebuild/Intake1.jpg>

It would be a bad day to ream the guide in an unguided condition only to 
find out that the stem is no where near centered on the valve seat 
anymore. That could mean removing huge amount of material to bring the 
seat back in alignment with the stem bore.

I found I spend way more time making the tools to do the repairs than on 
anything else. But the end result is well worth the trouble when you 
have a purring engine to listen to.
Curt Holland
Gastonia, NC



Richard Strobel wrote:

>Howdy all;
>  I'd like to ream my exhaust valve stem tower a little larger in dia. to 
>clean it up.  Question I've had for a long time...if I use a fixed dia. 
>reamer, and use a tap handle on it, do I need a pilot guide?..IOW, can I do 
>it by hand?
>
>  I know on some dad had, there was a pilot when it first starts out.
>
>  I'll leave it at that before I confuse myself :-)
>
>
>  Max Morgan in Boise, Id., will build me new valves for 35 rockets 
>each...not too bad IMO.
>
>  TIA
>RickinMt.
>
>
> 
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