Originally posted by Torx@Aug 18 2005, 10:50 AM~3650274
what tool do i need and how do i use it to test my oil pressure?
And how do you test leakdown or compression?
and whats the nominal pressure it should be at?
How do you replace the valve guides or seals(valve job) without taking the heads off?
whoa slow down there :biggrin:
1) You can buy an oil pressure gauge (or a set of oil, water temp and volts) and hook it up in the car. It's a nice addition anyway and great to monitor vital engine stats.
2) Compression tester - It screws into your spark plug hole. The way you are SUPPOSED to do it is to remove all the plugs while the engine is still warm, hold the carb to the floor while cranking with the tester screwed into the hole. I never do all this though, I do one at a time...seems to work the same but I guess its to unload the engine while testing :dunno: About having the engine warm, I think thats to simulate how the rings are sealing while the engine is somewhat warm since it runs warm...get it?
A leakdown test is done when you think you have low compression, you can squirt a few drops of oil in the chamber through the spark plug hole and see if the compression increases, stays the same or leaks down after a few minutes
3) Most people will say that compressoin should be about 10-15% equal within all cylinders. For example if you get 160, 155, 157, etc you are ok. Ideal is as close as possible. An exact number doesn't work due to temperature of the engine, etc but around 150 is normally what I've seen.
4) There is a tool that you screw into the spark plug hole that you plug into an air supply. This will push the valve up (after you remove the rocker arm and if the cylidner is at TDC). This keeps the valve from falling into the chamber and allows you to change what you need to. I've never used this tool or done it this way, but I think I seen it in Hotrod magazine way back when.
