flathead valve issue do I lap them back

saints

saints

Member
Ok hear it is I pulled the valve assembly out of all 16 holes and just left them loose in the block....I usually have a way of marking them so I can put them back in there bores when the block is cleaned but on this day it didn’t happen that way..... My son who loves to come out in the garage and help(he's 4) well he pulled all the valves and made a nice pile of valves so now I don’t know which bores they go and I’m missing 2 and can’t find them......after I fought the urge to scream at him and said thanks for the help buddy I’m wondering do I have to lap the valves back in since I don’t know there perspective homes....and I have some other valves from the same year block do I replace them and lap them in or do I need a machine shop to fit them so there’s no leaks????
thanks
 
I would bite the bullet and do a valve job, cut the seats and grind the valves... That will make for a long, good running engine... You don't mention adjustable or grind-to-fit lifters, that makes a bit of difference as to ease... Split or one piece valve guides? Those get mixed up, consider going to one piece guides... Karl
 
its a 8ba engine and its stock non adjustable I was hopeing I could just lap them.....will I need to get the hardned seats
 
A new valve job on a worn engine would be the proper thing to do but that does not mean that the engine you have does not have years of life left on the old valve job. A valve and corresponding seat are ground to raise, lower, narrow or widen the contact patch. Each valve and seat are ground to produce a contact patch that is the right width and centered in the middle of the seat or just towards the edge of the valve for a slight performance advantage. I would get some machinist bluing and see if you can match the valves and the seats back up again, It can be done. Here is a link to an excellent description of how to hand lap valves.

http://kz650files.kz650.info/adobe/Valve_Lap.pdf
 
A valve and corresponding seat are ground to raise said:
The valve face has nothing to do with the appropriate seat position and width. Assuming they are all ford valves, ground at the 45* angle, any valve can go in any position. There are intake and exhaust positions that usually have a specific intake or exhaust valve type. Often exhaust valves are found in both positions which is OK. You do not want intake valves in exhaust positions. Intakes are usually dished on top and exhaust are flat on top. There are exceptions in aftermarket replacements.
I think what Flathead Fever is suggesting is that there are wear patterns you could try to match up. That would be an agonizing guessing game hardly worth the effort as the results would most likely be wrong. If the seats are good, I'd have the valves ground. You could then lap the renewed valve face to get a good seal at the seat. Kind of labor intensive, but it is very doable. The issue then is the valve lash. The reground valves will fall lower in guides and there would be sufficient valve length to grind the stems to get the correct lash. Just make a jig so the stems can be faced very flat. This would save you a bunch of money, and would not be any less a quality job as what was usually done in the day. We tend to overdo rebuilds today, as standards have increased in the years, not to mention they use all new parts today to save on the high labor rates. Back in the day, the labor was less significant that the parts cost. no more. Now, if the seats are trashed, you have an all new ballgame. Have the seats ground and use your reground valves. PM me and if you want, I'll regrind your valves for the postal fees.
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LOL if you have nothing better to do for a couple of hours you can get the intake and exhaust valves seperated, as some one else said intake have a dish in them, if your lucky they havent been replaced with all exhaust ones, you know what the clearances are for the valves start putting on in the valve pocket and chech clearance till you find a valve pocket that the clearance is right or close, do all the intakes that way, then the exhaust, lap the valves and install, the two missing valves are another story, check the valves you have maybe you will find a couple that will work, if not find two that are to long and and have the stems cut to the right clearance, you can use exhaust valve in any posision , may look a little strange but it will be ok, no one will see it, take your time and you will be ok
 
What ever it takes to make it right I admire you for not yelling at him . If these young people loose interest in these old Fords then what ? Its nothing that cant be fixed . There is nothing that will make him loose interest faster than a bad experience . Believe me I have been there.
 
russ/40 I may take you up on the offer Thank you Kindly, and Ken/alabama I had to count to ten but hes always on my heel out in the garage "fixing" things with asserted wrenches he pics up around the garage...hope he keeps the fire going on these old cars
 
Seems like it's not yet been mentioned, you can do the '50-percent' separation of the valves, just by the color (you didn't mention cleaning them). The 'whitish-tan' = exhaust, 'black-ish' usually with black carbon-like deposits = intake. If we were closer, I could make the same offer as posted above - I have a valve facer, and seat-facing tools. Maybe you can find someone close to home that will help you out ?? In any event, I wouldn't 'just-put-it-back-together'. After I've gone to the trouble to get in as far as you have, I would always freshen up the valves... especially if I weren't the last person to do it. And, again, given that I'm that far into it, I'd be looking at the rings, too..... if I didn't already know the history of the engine. (I can be really 'frugal' when working on my own junkers, and I'm not above re-using many parts - like bearings & rings - if they check out ok. But, if I have the heads off, I would at least want to know that the valves are 'fresh', and that the rings are in 'ok' condition, with no broken rings, no burned pistons, no sloppy ring-lands.) JMHO.....
 
saints said:
russ/40 I may take you up on the offer Thank you Kindly, and Ken/alabama I had to count to ten but hes always on my heel out in the garage "fixing" things with asserted wrenches he pics up around the garage...hope he keeps the fire going on these old cars
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Not at all a bother, I'd be happy to do it for you. If you can't find the missing two valves, you should send two new ones, and I'll check them for you.

I'll PM you my address, and when you decide PM me that they are coming.
 
way back in the day valve jobs were common.i have done a couple that after doing them it blew the rings out and they smoked likr crazy
 
In the end, what is your time worth? Also, you really didn't tell us the plans for the rest of the engine? Are you just trying to throw it back together as a "runner" - and do the least amount possible, or are you trying to build an engine you plan to use for awhile?

Me (as a perfectionist!), I would most likely do a complete valve job done on the engine - as you have it this far apart, you've pulled the valves (not easy for most folks) and you already know you need at least 2 new valves. Also, you already have to buy a full gasket set - that is usually over $100 these days.

Pull it all the way down, have a valve job done and if the bores are good, then have the bores honed and put some new rings in it. It won't cost that much and you'll ensure that the end result runs well.

And check the crank and bearings while you're at it! ;)

Best of luck!

B&S
 
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