Author Topic: Valves Leaking ?  (Read 712 times)

Offline AMXguy

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Valves Leaking ?
« on: March 19, 2009 - 10:06:57 PM »
I wanted to CC my new heads , my question is with new valves , seats and all is it normal for fluid to seep into the exhaust and intake ports while you're doing this?  in the matter in a couple minutes it seeped enough to get them damp. does this mean I have a problem or is it normal?
1970 R/T SE Challenger
 1970 Superbee
 1969 S code Mach 1
 1967  GTO




Offline Chryco Psycho

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Re: Valves Leaking ?
« Reply #1 on: March 19, 2009 - 11:50:40 PM »
if the springs are on you may have a problem , if the seats are brand new they should wear in & seal better ,or the seat could be out of round or the guides loose new or used

Challenger - You`ll wish You Hadn`t

Offline AMXguy

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Re: Valves Leaking ?
« Reply #2 on: March 20, 2009 - 12:07:04 AM »
Yes springs are on, new seats, new  bronze guides and brand new valves.

 
1970 R/T SE Challenger
 1970 Superbee
 1969 S code Mach 1
 1967  GTO

Offline Chryco Psycho

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Re: Valves Leaking ?
« Reply #3 on: March 20, 2009 - 12:12:29 AM »
it will seat in

Challenger - You`ll wish You Hadn`t

Offline AMXguy

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Re: Valves Leaking ?
« Reply #4 on: March 20, 2009 - 12:20:20 AM »
Thanks,  I wonder if a guy could put some grease or something under the valves to make sure the cc reading is accurate? I don't think it's leaking that bad but a cc isn't much.
1970 R/T SE Challenger
 1970 Superbee
 1969 S code Mach 1
 1967  GTO

Offline 71chally416

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Re: Valves Leaking ?
« Reply #5 on: March 20, 2009 - 12:59:48 AM »
It's not normal for them to seep through. You probably have 100-110 lbs of valve spring pressure closed which should prevent that. You can do a quick "Quality control" check on the seats if you remove the springs and then pull each one closed sharply by the stem and see if any stick, or if they all easily open and close. If any stick closed (even a little) that indicates the valve head is wedging onto the seat because of valve seat run-out.  :2thumbs:
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Offline Kapteenikosmos

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Re: Valves Leaking ?
« Reply #6 on: March 20, 2009 - 03:41:02 AM »
You can also use the traditional suction type valve lapping tool to rotate the valve (without the springs ofcourse) on the seat. It should leave a narrow darkish ring on the areas where the valve head and seat contacts. This would show you if it is out of round etc. If the problem is minor, add some fine valve lapping compound and give it some turns. This is what I had to do on my previous daily driver with new seats & valves.

The machinist who did the seats had pretty poor tools and the valves were not actually even close for a good sealing. The guy was cheap so I didn't complain.

Ville

1967 six banger Mustang
1973 Challenger (under restoration)
1997 Lincoln Mark VIII LSC (daily driver)

Offline Aussie Challenger

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Re: Valves Leaking ?
« Reply #7 on: March 20, 2009 - 05:16:20 AM »
  I always put a smear of grease on the valve seat face before CC ing a combustion chamber.
  Whenmodifying a used head I clean then check the CC of each chamber before any machining so I know how much or little needs to be removed so they are close before machining.   :2thumbs:
Dave