Tried the search function but no luck. What is the tool called that inflates cyl. and what does it look like? I'd like to at least sound like I know what I'm talking about when I go to buy one. Thanks Ralphie
http://www.summitracing.com/parts/l...Sap3dhhc5HVeR4-7vrhJ6VE3D3Io2BpZ8khoCWkHw_wcB http://www.amazon.com/Lisle-19700-V...466884&sr=8-1&keywords=spark+plug+air+adapter Commonly used when valve springs or valve stem seals are replaced Comes with two-step fitting for both 14 millimeter and 18 millimeter threads Thread fitting to spark plug hole and other end to air supply Heavy duty 12" flexible hose allows easy access to spark plug hole and air supply Air pressure helps prevent the valve from falling into the combustion chamber
Wow! how fancy. Mine is an old spark plug. hollowed out with a piece of pipe brazed on and some old air hose with a quick coupler clamped on.
My compression tester has the same quick disconnect as the shop air hose. I prefer to shove a bunch of rope in the cylinder and rotate the piston up. It is easy to bump the valve too hard break the seal and have it drop with just air pressure.
You can also use a length of nylon rope, Feed it into the spark plug hole then hand rotate the engine to squeeze the rope into the valve faces. Works better than air if the valves bleed a bit or if the keepers need a bit of persuasion.
If you are in a bind or don't trust the air you can accomplish the task with a piece of nylon rope through the spark plug hole twirled as it goes in, then bring the piston up to hold the valves. Takes a little practice but it works. Note: Don't forget a handle on the rope so s... doesn't happen.
Spend some time to flush your air compressor and get a filter for it, air compressors are full of trash, water and nasty shit you don't want in your engine.
In my youth I have changed them out, a pair at a time, by removing the rockers and just feeding in a length of white, soft, nylon rope through the spark plug hole - leaving some hanging out - and bringing that cylinder up to TDC or until it squishes the rope filling the chamber and stops the piston. A $15 dollar valve spring compressor bar that uses a little leverage and out come the keepers. Valves cannot fall anywhere. Voila. Reassemble and move onto next pair. Just sayin' more than 1 way to skin it.
I've used the spark plug air adapter on my SBC several times, it works great. You need to use about 100 psi to keep the valves in place while you change out the seals. Another tip, use a little dab of grease on the valve keepers when you reinstall them, it helps keep them in place while you release the valve spring compressor. FYI, when you are hunched over concentrating on trying to reinstall the valve keepers, the air compressor will kick on and scare the sh*t out of you!
I use the rope method. It works and there isnt any danger of dropping a valve. If for any reason you lose the compressed air you could drop a valve and end up having to pull the head.
I've used both the rope and the air method. I once agreed to swap out a broken valve spring in my body man's chevy if he'd put some flames on my primered 56 Pontiac. I used a hunk of his mom's clothes line to do that one. Here's a very important hint: If you use compressed air, Always make sure the air is run through a drier before it's goes into your engine. I didn't and had to tear my engine down to repair rusty valves and seats after pumping moist air into it to swap out some valve springs. Engine sat a few months after doing the work and rusted.
There's the important part. DON'T use the starter to bring the piston to TDC. Also, if you're using the air pressure method, it's not a bad idea to loosen the radiator cap before pressurizing the cylinder. If the engine has a leaky head gasket or a crack in the right place you can end up pressurizing the cooling system. And it's not designed to handle that kind of pressure. Blowing a heater or radiator hose will make quite a mess. And if you're working on a hot engine the scalding coolant can cause a less than pleasant experience.
I believe I will use the rope method, seems foolproof and my air supply is anything but dry and truck will be setting for awhile so as Rocky suggested I don't need the rust possibility. Thanks again Ralphie
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