Turning down a valve stem

stan martin · Jun 8, 2006

I am in the process of rebuilding a four cylinder indian motorcyle. Seams anything to do with motorcycle parts the price doubles from auto parts, then add Indian Motorcycle and it doubles again. I need to replace the valve guides, and valves. Why can't I ream my guides around, and cut down a larger dia. valve to fit my guides? What type of reamer is recomended for the guides. Is there a place that sells valves by size? Thanks for any help. Stan

Gary E · Jun 8, 2006

If the price is only double consider it cheap. By the time you purchase stuff you dont now know where to get, and fool with operations that you dont have a clue about, the price will look cheap at 5 times what you think is high.

CatHead · Jun 8, 2006

They do sell oversize valves (+.015" usually), just reams and drop them in, if you can find them for your application...failing that, install bronze valve guide liners
There is proper valve guide reamers that are piloted on the end for about 3/4"...available from Goodson, the liners as well
Go the cheap way rebuilding an engine an you WILL regret it later!

JBishop · Jun 8, 2006

Hi Stan, you'll need a valve guide reamer, not too expensive I don't think, although if a 1 shot deal might be better off having an automotive mach shop ream the guides for you. It will only take a couple minutes and should be pretty reasonable. Trw and Sealed Power (same outfit now?) have catalogs with valves listed by dimensions, might be a section in the back of the regular catalog. Lots of things to consider, dia, overall length, length from head to retainer groove, what style ret groove, etc. I used to run a shop and did things like this on occasion, usually to fit larger valves. Probably have to look at the available valves to see if there is anything close before you do anything, thinking an old Indian may have valves with specs that may be hard to duplicate. You'll need access to a valve grinder to cut down and rework the heads of the valves. Good luck, Jim

Joe D Grinder · Jun 8, 2006

Many moons ago, we used to call perfect circle's facility in Haggarstown and ask for engineering, then describe a part by size and features. Did this often on piston rings, valves, etc. The guys there were so familiar with what they had that they could put you next to what you needed in a jiffy. maybe they still can. Also, it used to be common practice to knurl valve guides then ream them. Seemed to hold up well. I think K.D. tools made the knurls and reamers. They knurls sort of SCREWED through the guide, raising a ridge....Joe

Michael Moore · Jun 8, 2006

Stan, check with the folks at

http://www.blackdiamondvalves.com/

They sell blanks as well as lots of different replacement motorcycle valves and guides, and they will do custom work too. If you can provide dimensions they can probably come up with something pretty close to what you need.

cheers,
Michael

CatHead · Jun 8, 2006

Knurling, as mentioned above, is another option but its never as good as a new guide, as the valve only contacts the high points, they will wear out alot faster and heat disipation will be reduced

J. Randall · Jun 8, 2006

I am with Cathead on this one, while knurling will work, I never thought it held up very well. I would do it right. James

jimbo1490 · Jun 8, 2006

It's much easier to re-size guides than valve stems. If you must re-size a stem for some reason, it has to be ground rather than simply turned to get the proper finish.

Jimbo

menace · Jun 8, 2006

Don't forget the Indian was designed to run on leaded gas which lubed the valve stem and the guides also which probably weren't hardened to begin with so knurling and reaming, while not giving extended life should provide necessary lubrication not provided in todays unlead feuls.
Steve

Skeeter · Jun 8, 2006

Just have an auto machine shop put in hard valve seats. Then can use unleaded gas with very little problems if any.

Good luck on your rebuild.

bob308 · Jun 9, 2006

first i got into head work because i could not get a good valve job at the napa or other stores. they are in by 9 out by 5 and good head work takes longer then that.
now as far as the hard seats save your money you dont need them. reaming now lets think about that. you take a hole that is alredy over size pull some of the metal up and ream more metal out of it. lasts about as long as it takes to talk about it.

the best is to bronze wall the old guides or replace with bronze guides.

Evan · Jun 9, 2006

Just have an auto machine shop put in hard valve seats. Then can use unleaded gas with very little problems if any.

This is something I have wondered about for a long time. I have a 1959 Land Rover that I still use frequently. It was obviously designed for leaded gas. I have had it for 30 years and have never needed to do any work on the engine other than the usual minor maintenance. I have been running it on unleaded now for over 25 years. There is no sign of damage or problems with the valves and I don't use any additives.

What up with this anyway? It is a low compression engine so that may help some. It is possible that Rover used stellite valves since everything else is built to last a very long time. The engine is about 50hp and has 5 mains 2" wide.

stephen thomas · Jun 9, 2006

I've always wondered about the hardened seat and supposed lead "lube" of old motors. When tetra-ethyl lead first was introduced, the biggest problem was the lead causing valve and seat pitting and erosion at high temperatures.

Spiral expansion reamers passed clear through are the best and usually not that expensive, considering the value of the parts you are working on. Do not use adjustable machine reamers, they are meant to be adusted to size only for re-grinding and will lead poorly if you try to use them by adjusting, causing belled and non-straight holes. Some adjustable blade reamers will work "OK" if you are careful and have a test hole to set them to.

A buddy of mine has restored a number of 4 cylinder Indian & Xcelsior Bikes. If my memory holds, I'll ask him about the Indian valves and guides at Sunday breakfast at the airport. There's a car show and he'll most likely bring a car and some bikes if the weather's good.

smt

jimbo1490 · Jun 9, 2006

Evan,
It has always been possible to install valves that can hold up to more punishing conditions. Industrial, aircraft, air cooled and other markets have been doing so forever. You can add 'high-end' automakers to the list. It's just that the Detroit auto makers often used the lowest grade of steel they could get away with, which when TEL was still in the fuel, was pretty low.

The Land Rover was and still is a kind of high-end car, so I'm not suprised that they used good engine parts from day one, even before fuel additive issues truncated other options. Stellite heads are not necessary, BTW; just good a quality SS for the valves which is the standard now.

Ironic that Europe only very recently phased out TEL; we began doing so with the Clean Air Act of 1970. All TEL was out of street auto fuel in the US by 1985.

Jimbo

Evan · Jun 9, 2006

so I'm not suprised that they used good engine parts from day one

Yeah, the original exhaust system lasted about 25 years. Don't know what the pipes were made from but it wasn't ordinary steel. Some sort of SS I would guess.

Racer Al · Jun 9, 2006

As long as we're talking valves, I've asked on several occasions on different BBSs and never got a straight answer.

What is a good material to make hardened valve seats out of?

Thanks!

bluchip · Jun 9, 2006

Stellite?

bob308 · Jun 9, 2006

like i said before you dont need hardened seats. there was unleaded gas around since the 50's remember ammaco? it was the clean gas did not leave lead deposts in the motor. and there was no valve seat problems then. if the seat is beat out it was caused by something else, detitntion. leanout and brun the seat. or the guides so over size that valve bounces around and beats it out.

dfw5914 · Jun 9, 2006

It's usually vehicles that placed heavy demands on the engine that suffered for lack of hardened seats. If you operate in the "light duty" category you probably will not have any problem.
Motorhomes, tow vehicles, high performance vehicles and the like, really do need hardened seats.
Basically if you spend a higher than average amount of time at large throttle openings the valves and valve seats are going to get hotter.
A harder seat material will last longer under these conditions.
If you operate your vehicle under conditions that do not overly tax the thermal characteristics of your particular valve/valve seat combination, then there is no need for improvement.

Turning down a valve stem

Aluminum

Diamond

Hot Rolled

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Titanium

Titanium

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Stainless

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Aluminum

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Titanium

Diamond

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Titanium

Stainless

Stainless

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Stainless

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