Here's a good one. What's the trick, when changing valve seals, to keep the valve from dropping? Any suggestions? 1964 Comet Caliente w/ 260 LEATHERFACE
I take the valve out of my compression tester adapter, hook compressed air to the cylinder with a long breaker bar holding the crank from turning with that cylinder on TDC.
I've never done this but just curious -- if the piston is at TCD wouldn't the it keep the valve from falling out?
While it won't fall into the jug completely, it still drops down enough to prevent putting the keepers on again. The compressed air way is the only way to go.
I just did this not to long ago and used the rope trick. put said piston bottom of stroke,smack rotator with socket and hammer, snake in 4-5 feet of rope, crank piston by hand on end of crank until it stops, compress valve spring, remove keepers, remove valve spring compressor and spring, replace valve seal, reverse order. Strongly suggest if your going that deep in to replace the springs and keepers as well, 9 times out of 10 they could use it unless its a fresh rebuild.
...why the breaker bar? when i did mine, i removed all the plugs and used compressed air. the piston went to the bottom and the valves were closed... changed them 2 and went to next cyl. ......
Exactly the way I do it. With all the plugs removed, the compressed air easily turns the crankshaft and puts the piston at BDC and without the rocker arms installed, it makes no difference where the cam is located.
Any benefit using compressed air over the rope trick? My compressor loves to turn off/lose air out of the blue, and I would hate to drop a valve. (I'll be doing this on a 1993 Toyota 2jzgte)
Compressed air workes well as long as the rings/valves are good. The rope in the cyl positively holds the valves in place with no chance of dropping em, since the rope wont bleed off pressure. The downside is the rope is a bit time consuming to feed into the bore. Air is faster...Rope is safer if your worried about dropping a valve.
