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farmwrench@aol
02-21-2005, 08:37 AM
I have a '47 Avery tractor with a Hercules ZXB-3 (2 5/8 by 3"stroke) engine with bad valve guides and worn valves (AT THE STEM face is OK). It has pressin guides. I dont want to take it out of the frame. If NOS is unavalable or crazy $. I think I will have a real hard time finding vales from something else to fit (Stephen Chastain I think this is the same engine that your old generator has!) I think I can round up some one with a centerless grinder to clean up the stems and then I could make new guides. I bet the cost ofthe reamer will be about 4 valves.
What advice do you guys have. Recomendations on suppliers? Materials for make your own? Tips and tricks? BTW stems are 1/4 nominal so I'm out of the ordinary Goodson's smallest is .3XX" for guides

gunsmith
02-21-2005, 06:53 PM
Farmwrench: I have just finished restoring my 53 naa ford. I have some spare valves and a full set of guides left over. If you want, give me some dimensions and maybe what I have can be retroed to your size. For parts I used "Yesterdays Tractor Co." for my parts. They have parts for other machines as well.

CCWKen
02-21-2005, 07:31 PM
All the engine machine shops I know have cross reference lists for valves. I had one until my old computer went belly up. They can look up a valve by size. Take the old one in and have them match it. Depending on the "keeper" design, length may not be a problem. The stem and head diameter and the undercut will be the biggest concern. Some of the valves vary by only a few thousandths so measure accurately.

If you have to make your own guides, use a nickel-bronze. But check with the engine shop here too. They have lists by size for those too!

Forgot to mention:
Forget using the old valves. It's not worth it. A new valve should only be in the $8-10 range. Better quality steels and stronger.

[This message has been edited by CCWKen (edited 02-21-2005).]

andy_b
02-21-2005, 08:33 PM
man, i wish ALL valves were $8-10. ONE new valve for an old John Deere D is $125. i wish i knew how to make valves.
http://bbs.homeshopmachinist.net//smile.gif

andy b.

wierdscience
02-21-2005, 10:10 PM
I have reamed several guides for Onam gensets,the OEM replacements were $9.00 each,when the showed they were .025" undersized,reamed them myself,they turned out to be 12l14 leaded steel.

I also had a Herc JXD 6 cylinder,they are still in business,theye were pretty heavy in the oil field here.Parts were cheap for that engine,pistons were only $35 a hole.

3 Phase Lightbulb
02-21-2005, 11:03 PM
<font face="Verdana, Arial" size="2">Originally posted by farmwrench@aol:
I have a '47 Avery tractor with a Hercules ZXB-3 (2 5/8 by 3"stroke) engine with bad valve guides and worn valves (AT THE STEM face is OK). It has pressin guides. I dont want to take it out of the frame. If NOS is unavalable or crazy $. I think I will have a real hard time finding vales from something else to fit (Stephen Chastain I think this is the same engine that your old generator has!) I think I can round up some one with a centerless grinder to clean up the stems and then I could make new guides. I bet the cost ofthe reamer will be about 4 valves.
What advice do you guys have. Recomendations on suppliers? Materials for make your own? Tips and tricks? BTW stems are 1/4 nominal so I'm out of the ordinary Goodson's smallest is .3XX" for guides</font>


You should be able to use your old valves and just have your valve guides knurled then reamed to fit. The knurled guides work well due to the fact that oil gets hung up in the knurls. Go get a knurl/ream job and have them re-seat your valves and I bet you'll be happy for a long time with it.

-3Ph

CCWKen
02-21-2005, 11:36 PM
<font face="Verdana, Arial" size="2">ONE new valve for an old John Deere D is $125.</font>

Yikes! Reminds me of trying to get a relay for my Kubota. For $125 a shot, I would have cut new seats and guides and gone to a stock valve. What are they? New valves for my '25 Ford were only $6.

andy_b
02-22-2005, 12:01 PM
Ken,

i haven't needed any of these valves, but i did check the price on them just to see. of course, the cylinder bore is 6.5", so the valves are quite large. probably make a good umbrella for a child.
http://bbs.homeshopmachinist.net//smile.gif

andy b.

bob308
02-22-2005, 07:12 PM
i rebuild heads all kinds and there is only two ways to fix worn valve guides. replace them or bronze wall them. knurling last about as long as it takes to talk about it. i have welded the old j-d valve faces and recut them. you could make your own guides out of silicone bronze.

wierdscience
02-22-2005, 09:23 PM
Bob has a point,the old poppin John's would run in any shape,not much to those old motors.My brother and got a 630 gas we're are going through right now.I wonder if the guy who designed the exhuast knew he also designed a really good rain funnel? http://bbs.homeshopmachinist.net//biggrin.gif

J. Randall
02-23-2005, 01:56 AM
Bob, I agree on the knurling, I used to mechanic for a living and we tried the knurling for a while, to many comebacks so we quit pretty quick. James

farmwrench@aol
02-23-2005, 08:28 AM
Gunsmith, Thanks for the offer Guide ID=.2495 Stem=.2475 I think .500 OD on guide

I had a customer show up just as I was to get the length.

There is no undercut on this valve. 30 Deg seat angle (easy to change). AND I found a guy with NOS exausts for $8. But no luck on guides so I have to make 'em. Or have a shop cross some thing. The intakes are in the hands of a guy in Washington state and he wants $30 ea (rare stuff?) I am sure some other valve will cross. Keepers are 1/8 pin.

Could have the 8 valves redone for a few hundred at a local shop but would like to do it myself just for the thrill. I am concered about keeping concentric since they should be reamed once driven into the block.
Lots of advice on material. Nickel Bronze, Phoshor Bronze, Brass, Cast Iron If I get it right Yellow=better heat transfer+lubrication Gray=longer life ease of machineing.

rsanter
02-23-2005, 12:06 PM
I am lucky enough to have my own valve grinding equipment I could re-grind the valves for someone if they wanted to ship them back and forth. you should be able to buy new liners for the size you need. probibally for a very bug truck or something. if the inside was correct and the outside was too large, you could turn them on a mandrel.
one other thing, years ago I made a overhead valve system for a B&S motor by machining a head out of a chunk of aluminum. for guides I used several bronze bushings. 'full bronze guides' have been used in car applications for a long time, so I when I was working at a power tool repair place, I liberated some bushings that were the correct ID and reamed for the OD to be a press in fit and then I reamed through the 'stack' on bushings for a quick cleanup and installed the valves. I belive you can get bushings in nearly any ID/OD you can imagine.
another trick I have used is to get metric bushings that are just oversizes for a press in fit and then are just undersized so I can ream then to the final needed ID

bob

vim-engine
12-19-2005, 11:57 AM
<font face="Verdana, Arial" size="2">Originally posted by andy_b:
man, i wish ALL valves were $8-10. ONE new valve for an old John Deere D is $125. i wish i knew how to make valves.
http://bbs.homeshopmachinist.net//smile.gif

andy b.</font>

Kansas_Farmer
12-19-2005, 01:51 PM
Andy, be glad you don't have an R.