Valve stem seals

info2x · Post by **info2x** » 18 Sep 2016, 15:37

Hey everyone. Been working on replacing a lot of stuff on the Volvo recently and one of those items are my valve stem seals. I've got the valve cover off, the cams out, the tappets out and am ready to compress the valves. Per everyone's favorite write up (https://sites.google.com/site/incarvalv ... placement/) I'm using rope in the cylinder. The write up mentions that about 8 feet of 1/4" rope was used. Well I've used well more than that and then cranked down on the rope by raising the piston. Whenever I go to actuate the valve the valve doesn't stay in a single spot and instead goes into the cylinder. I'm only actuating maybe 1/4" because I don't want to do something I'll regret and have to pull the head. Do I need to go further to get the valve to disconnect from the keeper and retainer from the top of the valve? Could this be because of excess carbon build up in there or something? As I understand it I'm not applying force to the valve itself so I shouldn't be in danger of damanging a valve or piston, but this isn't what I expected.

I've tried this on both valves on cylinder 1. Cylinder 4/5 shown in picture

Thanks

Post by **JDS60R** » 18 Sep 2016, 15:48

Do you have an air compressor and a compression tester?
If so, remove schrader valve from compression tester hose ( so you can blow straight through it). Then connect compressed air to it. It will force the piston down and valves up. Leave the compressed air on while changing the valve stems and only remove it when springs and keepers are back on.

Post by **tryingbe** » 18 Sep 2016, 15:51

Yup, use compressor air. Makes life so much easier.

info2x · Post by **info2x** » 18 Sep 2016, 19:19

Sounds like I should be buying a compressor then...

info2x · Post by **info2x** » 19 Sep 2016, 11:00

What kind of pressure are people running for this operation?

Post by **tryingbe** » 19 Sep 2016, 11:24

I probably used 60psi.

info2x · Post by **info2x** » 24 Sep 2016, 14:16

Alrighty... Just got back from the garage where after pressurizing a cylinder and actuating the valves I still found the the valve is following the spring downward and in this case releasing the pressure inside the cylinder. I've tried 4 intake valves thus far, I'll continue onto the others but obviously I'm missing something here. Thoughts?

info2x · Post by **info2x** » 24 Sep 2016, 14:29

No luck on any valve. I was using 80psi. I had started lower and then went higher than 80, but it didn't seem to make a difference on at least two valves so I just left it at 80

Post by **tryingbe** » 24 Sep 2016, 15:31

I used a hammer to shock the valve keeper/lock loose from the valve retainer free first, then I use the tool on it.

So, put air in cylinder, use a tool that as like a rod between the valve retainer and the hammer, hit the tool with a hammer slightly, you'll feel the retainer move without the valve going down, then you'll know you can use the tool on the valve.

Post by **chrafael** » 24 Sep 2016, 15:35

Try placing a socket over the spring collar and giving a light but sharp rap with a hammer to dislodge it from the keepers. It's just wedged tight from age.