top dead center

tmar04 · Jan 31, 2008

just had a thought. when I get piston to TDC, and strike the top of valve spring,keeper, won't this drive the valve down, causing it to hit the top of piston? I don't like this idea. I need to be able to secure valve someway to keep it from going down into the cylinder.

rock2610D · Jan 31, 2008

Not sure why you would "strike" anything. Use a valve spring compressor, compress springs and remove keepers, then release compressor and remove spring. RIGHT??

mark777 · Jan 31, 2008

Hey Rock,

tmar04 is talking about replacing valve stem seals without removing the head.

It will be anything but easy/tricky to keep the valve stem height in place while collapsing the sping, installing the keepers.

I wouldn't hesitate to pull the head, dress the valves and seats (even hand lapping them) and re-assemble the head with a new head gasket. Reset the valve clearance and your good to go.....

Mark

tmar04 · Jan 31, 2008

Mark, I think you are right. I had the head off last week, but did not realize smoke was so bad. no big job to remove. thx

RobJ · Jan 31, 2008

tmar04 said:
just had a thought. when I get piston to TDC, and strike the top of valve spring,keeper, won't this drive the valve down, causing it to hit the top of piston? I don't like this idea. I need to be able to secure valve someway to keep it from going down into the cylinder.

It won't heart anything, just don't hit the valve stem. By hitting the spring the stem doesn't move much anyway. That's why this way of removing the keepers/springs works head on or head off. You don't need anything to back up the valve from the bottom. Even if you use a compressor, the valve may still hit the piston to free the spring retainer and keepers. Remember they've been stuck together for some time.

If you are really worried, just lightly hit the springs to loosen the retainer from the keepers, then just press the spring down by hand or with a wrench, have a helper use a magnet to grab the keepers. It'll still press against the piston...it has to...gravity and all.