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Chody
06-20-2012, 10:37 AM
whats the best way? Do i take the PlugWire off of the coil or the cap? then take spark plug out, screw in tester, and crank it over?:dontknow: never done this before, and im looking at buying a used engine.

Chopstick
06-20-2012, 11:16 AM
Yes. What u just said but make sure u pull your fuel pump relay too. And only crank it over a couple of times.

Apathy
06-20-2012, 11:22 AM
your fuel pump relay will not keep it from starting, just keep it from running.

PUll your main coil wire so there is NO fire to any spark plub. Turn it over, read pressure.
IF pressure is low, poor 1 cap of oil into the spark plug hole. If the compression comes up, its rings, if its the same, Hole in the piston, or something in the valves

Chody
06-20-2012, 11:30 AM
your fuel pump relay will not keep it from starting, just keep it from running.

PUll your main coil wire so there is NO fire to any spark plub. Turn it over, read pressure.
IF pressure is low, poor 1 cap of oil into the spark plug hole. If the compression comes up, its rings, if its the same, Hole in the piston, or something in the valves

if comp is low, im running away, but thanks for the tips.

does anyone have a tester i could borrow for saturday? its for an 89 5.0L

Apathy
06-20-2012, 11:36 AM
I think you can get a loaner from Lordco

Chody
06-20-2012, 11:49 AM
i hear they may only be about 20$, ill checkout cambodian and lordco

Chopstick
06-20-2012, 12:32 PM
PA has them for cheap too. I always pull the relay but the coil wire is an good idea too

4skin
06-20-2012, 12:45 PM
looking at the plugs will give a good indication of how it ran
plugs should be light tan colour not rust though lol
had a 5 litre that comp tested good
but smoked bad collapsed oil rings

yoda604
06-20-2012, 12:47 PM
Make sure you test it with the engine warm, better results.

Chody
06-20-2012, 01:20 PM
car is still running, he says good. i just want that lil extra insurance as its a 12 hour drive. that i have to do twice. as far as fuel, im gonna hit the inertia switch to trip the pump off.

kootenaycat
06-20-2012, 08:18 PM
Along with the inertia switch you can also either unplug the primary side of coil or pull coil wire off of distributor but make sure you ground it to the engine otherwise it will create a spark. If you pull it out of the coil that built up voltage has to go somewhere and may cause an arc-burn up the coil tower to find its way to ground.

Just get your buddy to stick his finger in the coil tower, that should do it. :D