Valve guide cutter issue

[jpwalt1987]

So I go to start cutting some valve guides on a set of stock iron heads to fit .530 viton seals. I have the .530 guide cutter from Comp Cams that I bought from Jegs. I get one guide cut down to height and go to put on a seal. It is loose as could be!! Wth? I start measuring everything and it turns out the ID of the cutter is .5255. The ID of the seal is the same size and therefore has no pressfit. I am guessing I have a defective cutter? Shouldn't the cutter have an ID of .530 and the seal have a ID of .525 for a .005 pressfit? What am I missing?

 

[bison]

The new cutter needs to be made dull or it will remove too much material. If you absolutely have to use a steel body seal then you should have someone with a known good cutter cut them for the .500" seals


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[jpwalt1987]

I already had the .530 seals so I figured I would use them. Luckily I tried it out on a set of junk heads. I guess I could try to clearance the cutter somehow. Don't understand why a .530 cutter would measure .5255 though...

 

[Chuck Leeper]

Ho Chi Min uses metric dimensions....

 

[jpwalt1987]

I used a piston ring cutter with a diamond wheel powered by a cordless drill to make quick work of adjusting the clearance of the cutter. Worked out great.

 

[turbodave231]

Jeremy,

I have run into this same problem with cutters from several sources including Goodson. Your fix is about the best that can be done.

 

[jpwalt1987]

Dave, it worked great. I did however run into an issue with the heads I wanted to use. They had been redone with +.015 valve stems. My junk head that I practiced on was stock 11/32 though. At first on the +.015 stuff I used metal tape for A/C ducting to get the desired dimension on the arbor. I did one head like that but had to change the tape after every two guides. I work at an industrial plant and we have shim stock of varying thicknesses so I grabbed a .001 and .002 shim and cut them to length to make a sleeve for between the arbor and guide. If I ever have to do another set of heads that have oversize stems then I will buy a 3/8ths arbor and have it machined to size.

 

[turbodave231]

I really hate valves with oversize stems!!!!! None of the standard tools work right and I can't get good pilots to cut the seats either. The expandable pilots aren't very good either. You end up with too much seat runnout.

 

[Powertechn2]

I have had the same issue with the expandable pilots. When guides are worn on industrial equipment heads and a standard pilot had too much clearance.