Valve guide knurling tool

[chipflyer]

I recently acquired a nice UTP Thread Master valve guide knurling kit and I am hoping someone has the direction sheet on how to use this tool and can share it with me. This kit didn't come with the directions but is complete otherwise. I used one quite alot 20 years ago and would like to see a direction sheet again before jumping back into knurling. Anyone out there have a direction sheet?

Thank you

Jeff

[ratkilr]

You posted this awhile ago. I just joined the board. I have the utp knurler you are talking about. Works great. I have the instructions and also the phone number of the company. I could scan the instructions and email them to you. The owner of the company may send you instructions for a small fee. Sometimes he is grumpy though, but they are still in business.

UTP knurling is the best way to recondition guides in my opinion. As you do it you can see the metal moving and the ghost pattern disapearing. I believe it also work hardens the guide, lasts longer and holds oil for lubrication. It also keeps the centerline of the guide so you have to grind less on the seat to true it up. If you core out the old guide for a new one and it is of a hair...you have to grind more seat and your valve will sit lower.

[Richard W.]

I disagree and think knurling is a waste of time. It's best to ream out and press in a hardened cast iron guide.

My reasoning is that you are trying to knurl cast iron which often breaks rather than allowing itself to be molded or reshaped like steel. Also you have less contact area, so it wears faster. Yes, it does hold more oil, but what is in the oil that's held there. Often it a hard abrasive material (carbon) thats held there and works like a hone stone against your valve stem, causing it to wear faster. So later on down the road you have to ream out for a hardened valve guide and buy a new valve too.

Richard W.

[Dan Baalman]

Richard over the years my brother in his shop and occasionally with my help, probably knurled well over a thousand cast iron guides with out a failure. The knurling works great with cast guides and the extra lubrication makes for an excellent long term result. I'm not saying it is any better than complete guide replacement, but every bit as good.

[stephen girouard]

there is another method, thin wall bronze inserts. many shops are now useing this method. it beats them all test after test. on iron guides knurling puts cracks in the guide with the pressure of the knurler, there also more practical then the more recent method of drillin out the old guide and changing it. there easy on the stems, tight toleranse , & seals oul well. Knurling new guides dont have the nickel& tin in the guide the old iron does, ( not as ductile) my first shop job we used to knurl pistons to fit back in a cylinder

[Richard W.]

Actually shops have been doing the bronze guides for years, I think it was about 20 years ago that I first heard of it. I have not been convinced that it's better than the hardened cast iron guides. My experience is that grit can get embedded in the bronze and cause damage to the stem. So if you miss an oil change and the bypass valve opens up in the oil filter, then you no longer have clean filtered oil circulating through your engine. It's this grit that can become lodged in the bronze guides. Now if you have an engine that has no oil filter like many older engines, you have got trouble coming.

Richard W.

[makoman1860]

Hey Guys,
Thought I could chime in here, I work in engineering on valvetrain and cylinder head development so ive been through All of this before.

Knurling an iron guide? Not a high quality fix, you end up with localized high contact pressure areas, and lots of place for burned oil etc. Best bet is to always replace guides, using materials that are compatabile with the valve stem material, and thermal loading of the engine, or simply put:

Air cooled engines-

Mild steel stem=Iron or bronze intake and bronze exhaust.
Stainless stem=bronze for both
Chromed stem=same as mild steel, may use dura-bar on the exhaust side.

Water cooled engines-

Mild steel stem=Bronze or Iron for both
Stainless=bronze for both
Chromed=Iron for both

Each material has its attributes and applications. There of course details on what exact alloys to use, clearances etc. If anyone wants specific help I would be more then happy to help them determine a material selection for valves, guides, and seats.

-Aaron

[stephen girouard]

i'd recimend stem seals on all aplications, the less oil in the stems the better

[makoman1860]

Sometimes yes, sometimes no. Depends on the materials, clearances, operating conditions, thermal loading etc. A valve seal is actually more complicated then one might think, and they are usually "tuned" to a specific application. Many of the newer designs are what we call "pumper" seals, that actually physically pump oil down the guide at a metered rate. History has shown that many of the sealing ideas from the 1970's lead to reduced valvtrain life, basicly live and learn. Also seal design and placement varies depending on how much oil is present on the parts themselves, so this changes with the lubrication system.

[Richard W.]

My son has ben scrapping out some cracked aluminum heads and they all have pressed in cast iron guides in them.

Richard W.

[stephen girouard]

i'v got a stack to, all iron guides with positive seals every one of them.gunna fit them with bronze liners in the guides & oem seals. the one's with seals arent worn bad. older one's without good seals are all worn out from that oil cookin in the guide & turnin carbon & galing stems, leavin heavy deposits in the engine. got nothin against the iron but try orderin & stockin factory guides for many aluminum head cars! you wont get no carbon ,dirty oil grit in the guide with good seals. rings are also iron & work adequate, until to much oil gets on them then they stick & gall.

[makoman1860]

Actually most of the guides you call "iron" in the modern aluminum heads, are actually a powdered metal (PM) material. One of the reason they last so long is that as part of the powder is actually solid lubricants. Federal Mogul PMF-2 is a very common guide material, probably the most widely used in the world on water cooled engines. Its some neat stuff, machines nice, wears well. Just dont use an un-plated valve stem on it.
-Aaron

[metalbutcher]

I am also of the opinion that knurling a guide is a good way to destroy a new part. In addition if knurling is used the knurl should not go all the way through the guide but end before it gets to the port end or it will create a nice channel to channel oil into the ports and it will smoke. You will be left scratching your head wondering why it smokes when after you just dropped a ton of money at the machine shop.