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Old 05-03-2006, 09:17 PM   #1
RShaips
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Valve guide seals ?

I need to change my valve guide seals on my truck. I have the body off the frame so now is the time to do it. I have never done this before , should I replace the O rings and also add the umbrellas seals ? I have read that you can put air into the cylinder or use a soft rope stuffed in there to keep the valves from falling, any preference? I guess all I need to change them is to buy the tool for $10.00 that will compress the spring and remove the retainer and spring and slide the old O ring off and put the new ones on. Thanks for the help.
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Old 05-03-2006, 10:26 PM   #2
Southpa
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Re: Valve guide seals ?

I've done it a couple times, each time I forget how, lol. You need the valve spring compressor tool and a fitting for your air hose that screws into spark plug hole. A good magnet helps too for removing those keepers, wouldn't want to lose them. I've never tried the string method and don't think I will. There would still be a chance for pushrod to slide down through the string.
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Old 05-04-2006, 09:07 AM   #3
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Re: Valve guide seals ?

Did you use the umbrella seals on top of the O rings or just replace the O rings?
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Old 05-04-2006, 09:53 AM   #4
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Re: Valve guide seals ?

I would use the umbrella seals & o-rings but, you really only need the umbrella seals on the intake valves. Also, I have recently fought with several types of spring compressors. My favorite one, as far as easy to use, is the one with the outdoor faucet type screw in handle on top. The cam-over, double handle type one is a PITA!! Also ir you're doing it with the heads in place, use some aluminum foil to block the oil drainback passages so you don't lose keepers.
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Old 05-04-2006, 09:57 AM   #5
Lemield
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Re: Valve guide seals ?

I did mine last year on my big block. I used the 'rope' method. I removed all the spark plugs and then did each cylinder one at a time. I took a woven cotton rope...about 25 ft....and slowly fed it into the cylinder until I could no longer get any rope in there. I then turned the engine by hand until the piston compressed the rope. I then used a lever type valve spring compressor to remove the springs and keepers. New seals from NAPA and on to the next cylinder. I did them in firing order and it worked fine. Using compressed air works great too but one advantage to the rope method is that the valve can't fall down into the cylinder....if for some reason you lost air pressure...bye bye valve...hello head removal.
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Old 05-04-2006, 10:17 AM   #6
RShaips
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Re: Valve guide seals ?

I think I may try the rope, seems easy enough since I can get to everything real easy without the body on. The tool I have seen at the parts store is just a long lever that looks like it bolts on one end and compresses the spring as you pull it, is this what i should use?
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Old 05-04-2006, 11:34 AM   #7
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Re: Valve guide seals ?

I just did this on 2 engines, an 88 and a 89. I would recommend getting Felpro valve seals. Use the Felpro blue positive seal on the intake and the the plastic umbrella on the exhaust. Use o-rings on both. The reason I say to use the Felpro is mainly for the exhaust side. Many brands use a black rubber umbrella for the exhaust, these get hard and brittle and break into little pieces when old, not only is the seal gone but all those little pieces end up in the oil pump pickup screen, Felpro has a hard plastic seal for the exhaust that won't break apart. Just my 2 cents.
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Old 05-04-2006, 12:14 PM   #8
Lemield
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Re: Valve guide seals ?

Quote:
Originally Posted by RShaips
I think I may try the rope, seems easy enough since I can get to everything real easy without the body on. The tool I have seen at the parts store is just a long lever that looks like it bolts on one end and compresses the spring as you pull it, is this what i should use?
Yep...thats what I used. I bought the lever type tool at NAPA too. The rope I used was cotton clothesline rope.
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1949 Willys CJ2A, Kubota Turbo Diesel engine, Warn Overdrive, 11 inch brakes, 12volt, Warn M8000 Winch "Little Green"
1970 Rustoleum Roller Red C20 Custom Camper 454 TH400 "Big Red"
1971 K20 6.2 Turbo Diesel 4x4 4spd Ranger Overdrive "Pumpkin Wagon"
2005 VW Beetle Diesel 44+ MPG "Silver Bullet"
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Old 05-04-2006, 03:41 PM   #9
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Re: Valve guide seals ?

While you have it off give the valve stem a wiggle you may find that the reason the old seals are bad are from worn guides and a total valve job is order.
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Old 05-04-2006, 04:06 PM   #10
RShaips
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Re: Valve guide seals ?

I bought the truck from a guy I know. The motor doesn't have many miles on it and runs very strong. It sat for several years with very little use. I am hoping that its just the seals. It smokes like crazy at startup and idle but doesn't smoke at all when you are driving it.
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