Compression test question

[tyndyn]

Pardon my ignorance, but I am trying to learn and do some stuff on my own.<br /><br />Is it ok and accurate to do a compression test at home with the hose hooked up to the motor?<br /><br />Thanks

 

[Dhadley]

Re: Compression test question

Naturally we assume you mean the water hose. No, it's not needed. The motor won't be running, only spinning over with the starter. <br /><br />It's a bit easier on the motor to have it warmed up first but not really necessary. Obviously you'll need the water hose if you warm it up first.

 

[Silvertip]

Re: Compression test question

Here's one more suggestion. If you really want to learn about your engine so you can maintain it yourself you really need to by a service manual specific to your engine. These engines have many very expensive parts that can be easily damaged by doing a procedure incorrectly. The cost of one "screw up" can be far more than the cost of the manual.

 

[emdsapmgr]

Re: Compression test question

Remove all the spark plugs before you do the compression test. Then check one hole at a time. Readings should be withing 10% of each other.