valve seal change info
Thread Starter
Advanced
Joined: May 2003
Posts: 51
Likes: 0
From: Silver Spring Md
valve seal change info
Well, I just ordered the umbrella type valve seals by FelPro the other day. My 74 is smoking pretty bad. I need to go and buy or rent a valve spring compressor, and was wondering what style tool you all have used that was the easiest? I saw this bar type at Napa the other day and thought it might get in the way of the carb or other parts on top. Im also gonna try the TDC method with string in the chamber instead of the compressed air method. Im a little nervous about putting all that compressed air in the motor. I have bad luck. Thanks for all the available input 
Melting Slicks
Joined: Mar 2003
Posts: 2,512
Likes: 49
From: Franklin IN
The compressed air is the way mechanics do it. I have a Snap-On compression gauge. The unit that screws into the sparkplug hole has a quick disconnect that connects to my compressor hose works great. The spring compressor only contacts the spring so not a lot of air is needed to keep the valve seated while you re-install the keepers.
Race Director
Joined: Jun 2000
Posts: 10,046
Likes: 675
From: FL
You don't need compressed air.
Rotate #1 cylinder to TDC on firing stroke (check distributor). Insert rope if you wish but with the piston at TDC, you have maybe 1/2" of clearance before the valve will stop at the piston anyway.
Remove rockers, pushrods. Remove springs, do seals, reinstall everything you took off. Since you are at TDC on the firing stroke, you can lash the valves right then.
Rotate crank 90 degrees. Do next cylinder in firing order.
I use the bar and it takes me about 3 hours to do all 16 seals.
Couple of tips:
- A light tap with a hammer on the retainer prior to using the bar will help free the keepers.
- Use a magnet to help remove the keepers.
- A dab of grease on the keepers will help keep them in place during the reinstall.
Rotate #1 cylinder to TDC on firing stroke (check distributor). Insert rope if you wish but with the piston at TDC, you have maybe 1/2" of clearance before the valve will stop at the piston anyway.
Remove rockers, pushrods. Remove springs, do seals, reinstall everything you took off. Since you are at TDC on the firing stroke, you can lash the valves right then.
Rotate crank 90 degrees. Do next cylinder in firing order.
I use the bar and it takes me about 3 hours to do all 16 seals.
Couple of tips:
- A light tap with a hammer on the retainer prior to using the bar will help free the keepers.
- Use a magnet to help remove the keepers.
- A dab of grease on the keepers will help keep them in place during the reinstall.
Racer
Joined: Jul 2003
Posts: 401
Likes: 0
From: texas,, at last
an easy way i've found of knowing when each cylinder is roughly at the top of it's stroke is,,,
i got an old distributor cap and cut the top off of it,
you can now easily see where the rotor arm is pointing,
i use it all the time when i'm working on the car,
neil
i got an old distributor cap and cut the top off of it,
you can now easily see where the rotor arm is pointing,
i use it all the time when i'm working on the car,
neil
Melting Slicks
Joined: Feb 2003
Posts: 2,330
Likes: 6
From: Long Island NY
This is my next project also. I'm going also with the Fel-Pro Umbrella seals. I was told that if mine came with o-rings only ('78 L-82) that I could use o-rings and the umbrella seals together... I was thinking to use the TDC method without air. I also have a cap with the top off...works great...
Thread Starter
Advanced
Joined: May 2003
Posts: 51
Likes: 0
From: Silver Spring Md
Awesome! I have been swamped with work this week, but I plan on doing them this week sometime. Thanks for all the tips. Im gonna go and buy the bar type today at Napa. Hey does anyone know the gap between the rocker arm and valve? I have a 74 base 350 motor. Thanks a load for all the help.
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Drifting
Joined: Aug 2004
Posts: 1,327
Likes: 5
From: 2010 C6 Grand Sport Convertible
I purchased a spring compressor from carquest that has 2 handles. One for holding the compressor, other for pulling down and compressing\locking the spring in the compressed state. I found it real easy to pull the spring\cap etc off with and stays together as one unit. The carb stays put and makes reassembly a snap. On my L-82, the 'O' rings were hardened like plastic and came apart in pieces in my fingers when I touched them. The part # for the Carquest tool is STL 16750, about 30 bucks. I installed umbella's in the exhaust and positive seals in the intakes. Supposed to be a good combo.
Good luck!
Mike
Good luck!
Mike
Last edited by 78pacer; Apr 25, 2005 at 10:05 PM.
Drifting
Joined: Aug 2004
Posts: 1,327
Likes: 5
From: 2010 C6 Grand Sport Convertible
Originally Posted by hdhamou
Well, I just ordered the umbrella type valve seals by FelPro the other day. My 74 is smoking pretty bad. I need to go and buy or rent a valve spring compressor, and was wondering what style tool you all have used that was the easiest? I saw this bar type at Napa the other day and thought it might get in the way of the carb or other parts on top. Im also gonna try the TDC method with string in the chamber instead of the compressed air method. Im a little nervous about putting all that compressed air in the motor. I have bad luck. Thanks for all the available input
Good luck!
Mike
Team Owner
Joined: Sep 2003
Posts: 88,393
Likes: 2
From: eville in
Originally Posted by 78pacer
I purchased a spring compressor from carquest that has 2 handles. One for holding the compressor, other for pulling down and compressing\locking the spring in the compressed state. I found it real easy to pull the spring\cap etc off with and stays together as one unit. The carb stays put and makes reassembly a snap. On my L-82, the 'O' rings were hardened like plastic and came apart in pieces in my fingers when I touched them. The part # for the Carquest tool is STL 16750, about 30 bucks. I installed umbella's in the exhaust and positive seals in the intakes. Supposed to be a good combo.
Good luck!
Mike
Good luck!
Mike
Melting Slicks
Joined: Jun 2003
Posts: 2,802
Likes: 241
From: Niles, MI
Originally Posted by 78pacer
I purchased a spring compressor from carquest that has 2 handles. One for holding the compressor, other for pulling down and compressing\locking the spring in the compressed state. I found it real easy to pull the spring\cap etc off with and stays together as one unit. The carb stays put and makes reassembly a snap. Mike
Drifting
Joined: Aug 2004
Posts: 1,327
Likes: 5
From: 2010 C6 Grand Sport Convertible
Hi guys,
I don't have any pics, since I'm not familiar with how to post them (my ignorance), and to the earlier posting, YES I replaced the tiny 'O' rings as well. I slobbered Assy lube all over the valve stems so the 'O'rings, umbella's and posi-seals slid right down easily.
Mike
I don't have any pics, since I'm not familiar with how to post them (my ignorance), and to the earlier posting, YES I replaced the tiny 'O' rings as well. I slobbered Assy lube all over the valve stems so the 'O'rings, umbella's and posi-seals slid right down easily.
Mike
Drifting
Joined: Aug 2004
Posts: 1,327
Likes: 5
From: 2010 C6 Grand Sport Convertible
Originally Posted by comp
cool 
how is it running ????
how is it running ????
