80 head

[xschop]

I just finished all the smoothing (very light porting) of a spare 1980-1 large valve head that was sitting for a long time off the motor with the cams installed. I removed all the valves and all 4 intake valves are bent and 1 of the exhaust valves are bent.The Clymers manual says to take to a dealer and check the valve guides. Is there a special tool I can check them myself. And should I just buy all new valves. The springs mic'd out as within the book specs, maybe only one of the larger "OUTER" springs read 39.8 (39.9 spec, IIRC). Also the head to motor mating surface has light gouging marks from P.O./ Storage. If I shave it, how much surface thickness to remove?......

[mro]

guide inside dia 7.015 mm

what is more important is stem to guide clearence.
Subtract ID of stem guide from valve stem dia

intake .01 to .04 mm
exhaust .025 to .055 mm
---

Early cams lift? be higher than 80's and they do run in the 80's heads w/o problems....so should be no problem removing that much from head, or run piston to TDC and measure where in relation to top of cylinders, then measure how far down valves will extend from head...should then be able to figure valve piston clearence. Got CRS right now and don't remember what is considered minimum piston/valve clearence.


mro

[xschop]

walking encyclopedia

if you recall that off your head. So, how do I measure the I.D. of the guide? The valve stems were just a tad under 7mm IIRC. Thanks MRO. I want the best breathing head poss.

[DiverRay]

Chop, There is a tool for that! Check some of your local shops, and see if they have it. Worst case, check Harbor Freight and see about getting a China made tool to do it. You WILL need a good micrometer to use with that, and NOT one of the types used for setting float levels.

[xschop]

seeing is believing

I never messed with valves before other than installing brand new ones in a Porsche head. I will call an auto machine shop and check what they use,Thanks....chop....

[DiverRay]

Chop, IF you know them, maybe they can measure for you, and then you KNOW the specs. Good luck!

[egsols]

Search for small bore gauge kits. There are a bunch on ebay.

[xschop]

New valves

I am going to buy all new valves. 5 of them are bent (just by eyesight). So, should I just take it to an auto machine shop and check the guide measurements or can those be bought new and installed also? Or am I worrying to much. I just can't believe why these intake valves were All bent from a donor bike and if that can jack-up the guides....

[SFerinTEXAS]

I did some time years ago in my brothers engine machine shop. We checked the guides with the valves when the springs came off. If you can rock it noticably and the valve stem is not worn then you need guides, if the valve moves in and out smooihly and it doesnt rock around then you should be allright. Just my 2 cents

[mro]

I've had a couple XSes apart with 30,000 to 40,000+ miles on em. Guides were fine.
But if not sure get one of these



mro
BTW, thought you worked/played in a machine shop???

[xschop]

guage

I checked the Bay and they only have down to an 8mm boring guage. Then googled it and found one for 749.00 that can go the lower dia. needed. I have decided to err on the side of experience (thanks SFer n tejas and especially TRBIG) and just buy all new valves and stick them in and check the good ol' way. Mro, that guage will only measure the I.D. of the bore to it's limiting depth, not all the way through. I'm a perfectionist (especially when it comes to working on my crap) ....and don't want to chance tearing it down after I have put in the dirt on the build.....I actually own alot of tools/equipment/ CNC/ Lathe/ mill/ machinery etc and do machining work because I enjoy it. Two of my friends (both master machinists) taught me everything I know over the years.

[egsols]

Would this one work?

http://cgi.ebay.com/4-pc-FULL-BALL-S...QQcmdZViewItem