Compression Test Procedure ? I am doing this right?

[mreinsmith]

I just need to make sure if I am doing this right. (and if so, the reasons why if someone would be so inclined to explain it)

1 ? Ground all 4 plug wires (That one is easy, to prevent spark)

2 ? Remove all plugs

3 ? Set throttle Wide Open (I set it at least as far as the control would go with the trans disengaged)

4 ? For each cylinder, I cranked engine 4 to 6 times to allow pressure to build.

I got 110 on all the cylinders except #2 which read 50.

I?m going to try a seafoam treatment next.

Let me know if I?m missing anything or there is more I need to do.

Thanks a million

 

[baxtr]

Re: Compression Test Procedure ? I am doing this right?

sounds good, other than the comp on # 2

 

[mreinsmith]

Re: Compression Test Procedure ? I am doing this right?

thanks, wish me luck that the seafoam saves the season.

 

[JB]

Re: Compression Test Procedure ? I am doing this right?

It is not necessary to open the throttle. It has no effect, and it is difficult to do with the gearcase in Neutral.

Rather than grounding the plug wires, it is better to leave the ignition off and use a jumper or remote starter switch to run the starter.

If you really want to do it best, warm the engine up before starting the test.

 

[mreinsmith]

Re: Compression Test Procedure ? I am doing this right?

Thanks JB,

We're running a decarb with seafoam now, when done we'll do itthe way you suggest.

 

[Frank Acampora]

Re: Compression Test Procedure ? I am doing this right?

I hate to rain on your parade, but with 50 psi on one cylinder, seafoam and decarbing 'aint gunna do squat. You might as well bite the bullet and pull the head. Most likely you have a stuck set of rings due to the piston galling in the bore. You have my number, I will be home Saturday after 5 PM.

 

[mreinsmith]

Re: Compression Test Procedure ? I am doing this right?

Yeah, we came to the same conclusion.

I'm reading up on the procedure for the rings.

If anyone has some tips or "watch out for" items don't hesitate to let me know.

I'm sure I'll be back out here on the subject soon.

Thanks

M

 

[TexasBayFisher]

Re: Compression Test Procedure ? I am doing this right?

I'm sure I'll be back out here on the subject soon.

Thanks

M

It's 2009, what happened?