1995 225 MERCURY OFFSHORE EFI COMPRESSION

[MARKM3144]

I AM NEW TO THIS SO I WILL KEEP IT SHORT! I AM TRYING TO FIND OUT WHAT THE COMPRESSION ON A 1995<br />MERC 225 EFI OFFSHORE SHOULD BE. I AM LOOKING AT A BOAT WITH THIS MOTOR. COMPRESSION CHECK COLD SHOWS 105 IN ALL CYLINDERS IS THIS OK FOR THIS MOTOR?

 

[Kenny Bush]

Re: 1995 225 MERCURY OFFSHORE EFI COMPRESSION

seems a little low. Should be about 120-125 (warmed up). All of the readings should be 10% of each other or no more than 10 to 15 lbs difference between cylinders.

 

[MARKM3144]

Re: 1995 225 MERCURY OFFSHORE EFI COMPRESSION

ALL CYLINDERS ARE WITHIN 2PSI COLD.WOULD THIS CHANGE IF MOTOR WAS WARMED?MOTOR SOUNDS TIGHT AND RUNS GREAT. ANYTHING I SHOULD LISTEN FOR ON A TEST DRIVE? I AM GOING THI WEEKEND TO RUN BOAT.

 

[MARKM3144]

Re: 1995 225 MERCURY OFFSHORE EFI COMPRESSION

***

 

[MurdockJr]

Re: 1995 225 MERCURY OFFSHORE EFI COMPRESSION

Yes your readings will go up with the engine warm. Numbers sound good cold. Good Luck!!

 

[MARKM3144]

Re: 1995 225 MERCURY OFFSHORE EFI COMPRESSION

THANKS FOR THE RESPONSE I WENT THROUGH THE ARCIVES AND DEALING WITH COMPRESSION IT SEEMS TO BE A TOSS UP.SOME SAY AS LONG AS THE NUMBERS ARE CONSISTANT AND WITHIN 10LB ALL SOUNDS GOOD, AND SOME SAY 110#-120# ONLY.SEEMS TO BE 50/50 IT GETS CONFUSING.ANY HELP IS APPRECIATED!

 

[dick]

Re: 1995 225 MERCURY OFFSHORE EFI COMPRESSION

For that motor those #'s are fine.Larger loop charge engines have lower compression , as long as they are within 15% not psi of each other you good.I had a 175 Rude that had 90 Psi on all 6 and was the smothest engine I ever had.<br />Just a note , don't us caps all the time it means your YELLING.

 

[MARKM3144]

Re: 1995 225 MERCURY OFFSHORE EFI COMPRESSION

Thanks for the info I appreciate the yelling info<br />and the info provided here in this forum.Any information helps me make the correct choice. Buying a used boat can be quite trying.The hull and electronics are the easy part the motor is a different matter.

 

[MARKM3144]

Re: 1995 225 MERCURY OFFSHORE EFI COMPRESSION

Thanks for the info I appreciate the yelling info<br />and the info provided here in this forum.Any information helps me make the correct choice. Buying a used boat can be quite trying.The hull and electronics are the easy part the motor is a different matter.