merc 800 /compression too hi?

[buddyp]

1969 merc 800...stock original powerhead..lubed the cylinders..throttle wfo..all plugs out...comp readings with a known gauge...165..170...165...170..1-4...does this seem hi?

 

[SeaKaye12]

Re: merc 800 /compression too hi?

It's a bit high...but the numbers are even. That's the most important thing.

Gauges vary; can you re-take the readings with a different gauge? Are you thinking that you might have some carbon in there?

Chuck

 

[buddyp]

Re: merc 800 /compression too hi?

Maybe...will treat with mrec power tune after I get it running...firat its replacing all the hoses and maybe top and bot seals..carb kits..ect!

 

[Moody Blue]

Re: merc 800 /compression too hi?

I've got a '71 Merc 800 and get the same high readings. Not sure if that is typical or not. Have not done a decarb on my motor.

 

[buddyp]

Re: merc 800 /compression too hi?

Is your motor low hour?

 

[Gomer50]

Re: merc 800 /compression too hi?

I have got a 1972 Merc 800 and would love to see those high numbers.Mine is a little tired and reads in the 120's +/- 10%.