pearldrum944

I may have a broken valve spring. On a 944, is there any way to install new springs without removing the head?

PorscheDoc

I dont see how you would compress the spring. Normally you use the bottom of the valve and the top of the spring as your contacts, and compress together to pull the retainers.

CO944

You would be flirting with the devil if you actually could do this.
You need to pull the head to replace a spring.

KuHL 951

Supposedly you can set that cylinder at TDC, lock your flywheel at the starter, and use a leakdown compression tester to pressurize that cylinder and keep the valves closed. This is assuming you have good compression. Someone makes a valve spring tool that bolts to the head for in-place work.

brad-cam

I made a tool out of a flat piece of steel 1.5" wide, 1/8" thick and 4-5" long. Drill a hole in the middle for the valve stem to come through and two bolt holes to bolt the plate down to the head using the cam cover bolt holes. You need to do some trial and error to get the holes in the plate in the right place. You also might need some washers or spacers to put the right amount of compression travel on the spring to get the keepers out. You can do this with the head off, or use the pressurization approach mentioned by KuHL 951 (ie. use an air compressor to keep the cylinder pressurized through the spark plug hole.

I had a hell of a time finding a valve spring tool that would fit around the spring. The head material comes very close to the spring and makes it hard to get traditional tools around the spring. Hence, I made a tool...

Good luck. BTW, I also had a broken valve spring...

njwilser

There is also the crafty method of feeding a length of soft rope down into the cylinder on the downstroke. W/ the right amount of rope in the compression chamber it will supposedly hold the valves shut while the spring is replaced. Never done it, just impressed w/ the creativity to solve the problem.
MW

Mike C.

It is a fairly common practice to lock the crank in position with the cylinder in question at TDC on the compression stroke and then pressurize the cylinder via the spark plug port. This way, even if the valve loses seal and slips down, it can't fall beyond the 'point of no return'. You should be able to find an adapter to do this at a good auto parts store - but you will need compressed air. You will also need a valve spring removal tool. The rope trick sounds like it might work though.

seb928s

I just want to know why you would want to do it while it's on the car? You might aswell unscrew the bolts and replace the head gasket while you are in there. Maybe you have replaced it not that long ago then I understand.

hoffman912

dont just replace one spring, replace all teh springs. i have found in my experience, if one goes, more will follow.

Blitzen

I just broke a spring on my '96 951. No valve damage, so we left the head in place & replaced all the springs, valve seals and the one trashed keeper.

AlexE

As has been mentioned ....

Compressed air is your friend.

Super easy to do with the head in place.

*Don't use the rope trick. I have seen some NASTY results from doing this.

pearldrum944

I'll have to look into the compression test trick and consider it. I do not want to pull the head because I'm tired of doing it...I have practice, I guess if I need to this time it will be my fifth? I'm tired of having to replace the head gasket and I only have a few weeks before 944fest. Thanks for the help.

seb928s

Tyler I didn't know you replaced the head gasket before. That is the case then just do it while it's on the car. I just don't like the idea that some do "oh here is the problem so I'm just fixing this" while the person just could do a little more and not have that problem come up a month later.

Mike C.

Unless replacing a good head gasket is your idea of fun, do it without removing the head. But hey, beauty is in the eye of the beer holder, etc, etc....

pearldrum944

Awesome, looks like my springs are fine. I'll keep this in mind for future reference though.