compression test safety

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strada-caster
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compression test safety

Post by strada-caster »

just curious if disconnecting the glowplug power is safe enough, or is there a way to stop fuel to the engine to perform the test?

Don't want the engine starting during the test.
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Golf Cart
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Re: compression test safety

Post by Golf Cart »

strada-caster wrote:just curious if disconnecting the glowplug power is safe enough, or is there a way to stop fuel to the engine to perform the test?

Don't want the engine starting during the test.
Take out all 4 glowplugs to avoid any pressure build in the cylinders, and ya might want to do it on a cold engine
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Re: compression test safety

Post by thedjjack »

back of the injector pump is the electrical switch that cuts fuel (I cannot remember how the power goes through it)....I would also second the pull all glow plugs (for a proper compression reading you only want the cylinder testing to have compression).
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Strada 92
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Re: compression test safety

Post by Strada 92 »

If you don't want that the engine start,disconnect the wiring at the back of the fuel pump.There is a square connector with six or eight wire,don't remember.It is black.
It cut glow plugs,fuel shut-off solenoid and other electrical of the engine.The engine crank but doesn't start.
Mitsubishi Strada Ralliart 1992 (sold)
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strada-caster
Posts: 260
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Vehicle: Mitsubishi Strada 1992
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Re: compression test safety

Post by strada-caster »

did my compression test this weekend. from the fan to the output shaft
fan
cyl 1 440 Psi
cyl 2 405 Psi
cyl 3 405 Psi
cyl 4 440 Psi
output shaft

The test equipment came with recommended process to follow.
ensure truck is at operating temperature,
disconect fuel solenoid(back of IP),
remove all glowplugs.
attach gauge to one cyl.
depress clutch and gas pedal
crank starter 8 times
take reading.
do the next cylinder...

My numbers came close to the 10% variance, but with a couple more cranks on the starter, the 2 lower cylinders came up to 440 Psi.

I got my compression tester off ebay for 80 bucks to my door.
hope this helps someone else.
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