Valve guides

Do you have the factory Honda service manual for your vehicle? There may be specific recommendations regarding the process for changing the guides. For example, heat the head first, then drive the old guide out, and install the new. Either which way, you must ream the guides to the proper clearance. If you have the proper reamer, you may not need to hone them as well. What you must do, though, is perform a "valve job", and cut the seats. The new guide is unlikely to exactly match the old, so you need to true the seats to be concentric with the new guides. Neeway makes some nifty cutters, but they are not cheap.
 
Make sure to measure the valve stems and the guides before assembling them. I did not do that on my three wheeler when I got new valves and the exhaust was a thou over size, stuck the valve, bent it and ruined the guide. Better to not learn the hard way.
 
Neese1 covered the big one above.You want to do the guide, and then use the correct pilot and cut your valve seat. I have the Neway set up also, and it does a nice job including multi angle, and bowl entry. Not as fast as a Serdi, or similar, but can be just as accurate. Bought them many years ago when I was doing head work and porting on Harley stuff. Sounds like your employer might provide everything you may need. Let us know how it goes. Mike

Pevehouse said:
I will buy the appropriate tooling. Probably won’t be my last one. This company has several of these things. I just wasn’t sure if I was looking at reaming or honing them in. I appreciate your expertise. I have a service manual coming that should have my specs in there. Any thing else I should know?
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One ,why are the valves over sized. This whole thing makes no sense. Sure you can ream the valve guides out to fit. But why. Aren’t the standard sized valves available?
 
Nesse1 said:
Do you have the factory Honda service manual for your vehicle? There may be specific recommendations regarding the process for changing the guides. For example, heat the head first, then drive the old guide out, and install the new. Either which way, you must ream the guides to the proper clearance. If you have the proper reamer, you may not need to hone them as well. What you must do, though, is perform a "valve job", and cut the seats. The new guide is unlikely to exactly match the old, so you need to true the seats to be concentric with the new guides. Neeway makes some nifty cutters, but they are not cheap.
Click to expand...
Thank you, that’s the kind of information I was looking for
 
FOMOGO said:
Neese1 covered the big one above.You want to do the guide, and then use the correct pilot and cut your valve seat. I have the Neway set up also, and it does a nice job including multi angle, and bowl entry. Not as fast as a Serdi, or similar, but can be just as accurate. Bought them many years ago when I was doing head work and porting on Harley stuff. Sounds like your employer might provide everything you may need. Let us know how it goes. Mike
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I will go look for the set now, thank you
 
Nutfarmer said:
One ,why are the valves over sized. This whole thing makes no sense. Sure you can ream the valve guides out to fit. But why. Aren’t the standard sized valves available?
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Kinda, and yes and no.

Different manufacturers have run into problems with their designs and were forced to come up with solutions. This is more true for modern "High strung" engines that older stuff. I think it was Kohler? that couldn't keep exhaust seats in their opposed twin blocks for a while.

Ive dealt a lot with old Gravely equipment and they were made 3X as stout as needed to be and therefore you could do a complete engine overhaul out in the middle of a field with simple hand tools.

Had to be that way as you weren't likely to move a non running unit by hand, even with help.
 
Nutfarmer said:
One ,why are the valves over sized. This whole thing makes no sense. Sure you can ream the valve guides out to fit. But why. Aren’t the standard sized valves available?
Click to expand...
Those guides can be kind of generic. Length, inner, outer diameter can be massaged to serve in various cylinder heads. Engineers through the years saw reason to increase valve stem sizes due to different materials used.
O.D. of the guide is increased in some cases to compensate for their bore in the cylinder head needing enlarged and trued because of a guide coming loose and beating it's hole o/s and out of round.
 
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