Problem with Valve Spring Compressor

930cab89 · 11-20-2010, 02:57 AM

I've put the Pelican recommended Valve Spring Compressor in place on the engine of my 930 but it does not compress the spring enough to be able to remove the split cotters. I lift the valve all the way up but it's still not enough.

What am I doing wrong? Thanks in advance for the help.

MBruns · 11-20-2010, 06:29 AM

It may be moving the valve along with it, try snaking a little rope down the plug hole just before TDC and then move the piston to the top to hold valve in place, or if you have a leak down tester secure the crankshaft at TDC add some air and give that a try

Mike Bruns JBRacing.com

930cab89 · 11-20-2010, 08:09 AM

The piston is at tdc and I put compressed air through the spark plug hole. The valve is completely closed but still the spring doesn't compress enough.

cgarr · cgarr's Garage

Is the top cup binding on the stem maybe? That should push down rather easy.

pete3799 · pete3799's Garage

Cut a washer (or 2) in half and place between valve and compressor.
Or grind down the end that bolts to the cam tower so that you have more travel on the compressor.

930cab89 · 11-21-2010, 04:13 AM

Thanks for the advice. I think I will find a install a longer bolt.

MBEngineering · 11-21-2010, 08:35 AM

HI 930cab89
is that a tyre pressure gauge you are using?????? and the rearing is at 0 or has the gauge round past the 12, I would say it is at 0??

you need as MBruns has recommended A "leak down tester" secure the crankshaft at TDC add some air and give that a try, with a continual supply of air into the cylinder to hold the valve closed and do not remove the air when you have the spring off!!!!

regards mike

john walker's workshop · 11-22-2010, 08:40 AM

there are different tools for intake and exhaust. never had that problem with mine.

930cab89 · 11-22-2010, 11:59 PM

I put a tyre valve inside an old spark plug to put air into the cylinder. But in this case, I have access to the valve from the outside as the exhaust headers have been removed. I just push the valve up with my finger and yes, I have the right tool for the exhaust valve (I have both).

DanielDudley · 11-23-2010, 02:26 AM

If that thing is compressing the spring, sometimes you have to take a brass drift and tap on the cap under the keepers to pop them loose. They get stuck tight in the hole, and you need to tap the hole down from them.