texasfishingforum.com logo
Main Menu
Advertisement
Affiliates
Advertisement
Newest Members
TraeMartin, Power-Pole CS, T-Rigger, JoeGoes, EcKo
119150 Registered Users
Top Posters(All Time)
hopalong 120,565
TexDawg 119,511
Bigbob_FTW 94,879
John175☮ 85,892
Pilothawk 83,259
Bob Davis 81,478
Mark Perry 72,280
Derek 🐝 68,311
JDavis7873 67,416
Forum Statistics
Forums59
Topics1,037,807
Posts13,934,808
Members144,150
Most Online39,925
Dec 30th, 2023
Print Thread
Outboard motor compression #14086625 08/06/21 11:53 PM
Joined: Jun 2004
Posts: 601
C
Crappieshooter Offline OP
Pro Angler
OP Offline
Pro Angler
C
Joined: Jun 2004
Posts: 601
Is 95 psi enough compression for an outboard motor. Looking at buying a boat and was told the compression check showed 95 psi on all cylinders. Good or bad?





Re: Outboard motor compression [Re: Crappieshooter] #14086666 08/07/21 12:51 AM
Joined: Apr 2008
Posts: 12,330
P
PaulGrapevine Offline
TFF Guru
Offline
TFF Guru
P
Joined: Apr 2008
Posts: 12,330
2 stroke or 4 stroke motor? If it’s a 2 stroke then I’d be okay with it.

Re: Outboard motor compression [Re: Crappieshooter] #14086696 08/07/21 01:22 AM
Joined: Mar 2014
Posts: 3,900
T
Topwater2 Offline
TFF Team Angler
Offline
TFF Team Angler
T
Joined: Mar 2014
Posts: 3,900
Told? Get it in writing.


FishKen
Re: Outboard motor compression [Re: Crappieshooter] #14086725 08/07/21 01:50 AM
Joined: Jan 2005
Posts: 16,636
P
Pat Goff Online Content
TFF Guru
Online Content
TFF Guru
P
Joined: Jan 2005
Posts: 16,636
Depends on the motor.
95 is fine on a old Johnson.
On a V6 merc it would be sick.


Pat Goff
Seadrift TX
[Linked Image]
Re: Outboard motor compression [Re: Crappieshooter] #14086775 08/07/21 02:44 AM
Joined: Jun 2004
Posts: 601
C
Crappieshooter Offline OP
Pro Angler
OP Offline
Pro Angler
C
Joined: Jun 2004
Posts: 601
2002 Mercury 2 stroke.





Re: Outboard motor compression [Re: Crappieshooter] #14086776 08/07/21 02:45 AM
Joined: Sep 2003
Posts: 1,889
C
Coolarrow Offline
Extreme Angler
Offline
Extreme Angler
C
Joined: Sep 2003
Posts: 1,889
My old 96 Johnson 150 has 120 on all 6 so I’m not sure. What kind of motor and year? The

Re: Outboard motor compression [Re: Crappieshooter] #14086777 08/07/21 02:46 AM
Joined: Sep 2003
Posts: 1,889
C
Coolarrow Offline
Extreme Angler
Offline
Extreme Angler
C
Joined: Sep 2003
Posts: 1,889
Originally Posted by Crappieshooter
2002 Mercury 2 stroke.

HP?

Re: Outboard motor compression [Re: Crappieshooter] #14086785 08/07/21 02:50 AM
Joined: Sep 2003
Posts: 1,889
C
Coolarrow Offline
Extreme Angler
Offline
Extreme Angler
C
Joined: Sep 2003
Posts: 1,889
I know a 90 hp has about 120 psi in that year model range.

Re: Outboard motor compression [Re: Crappieshooter] #14086822 08/07/21 03:23 AM
Joined: Aug 2010
Posts: 620
F
FlyFX Offline
Pro Angler
Offline
Pro Angler
F
Joined: Aug 2010
Posts: 620
always take a compression gauge, some lube and a plug wrench to survey a boat


Most people double haul so they can throw their mistakes further - Bernard "Lefty" Kreh - R.I.P.
Glass rod, click & pawl, ugly flies
Re: Outboard motor compression [Re: Crappieshooter] #14086859 08/07/21 04:14 AM
Joined: Jan 2005
Posts: 16,636
P
Pat Goff Online Content
TFF Guru
Online Content
TFF Guru
P
Joined: Jan 2005
Posts: 16,636
Compression gauges can vary from one to another. What you’re really looking for is a misfit cylinder. Sick motor will have five at 120 and one at 90. On your three cylinder take all the plugs out, pull the kill switch and spin each hole. If they are all the same it’s what you want. If one is more than 10% different there is an issue.


Pat Goff
Seadrift TX
[Linked Image]
Re: Outboard motor compression [Re: Crappieshooter] #14087865 08/08/21 04:00 PM
Joined: May 2011
Posts: 1,868
P
pil,b Offline
Extreme Angler
Offline
Extreme Angler
P
Joined: May 2011
Posts: 1,868
Leak off test

Re: Outboard motor compression [Re: Crappieshooter] #14096530 08/16/21 03:17 AM
Joined: Jun 2004
Posts: 601
C
Crappieshooter Offline OP
Pro Angler
OP Offline
Pro Angler
C
Joined: Jun 2004
Posts: 601
Thanks for the replies, passed on the motor.





Re: Outboard motor compression [Re: Crappieshooter] #14103296 08/21/21 03:55 PM
Joined: Nov 2002
Posts: 4,439
Gamblinman Offline
TFF Team Angler
Offline
TFF Team Angler
Joined: Nov 2002
Posts: 4,439
Compression check is really only to determine if you have bad cylinder. If you want to know the real health of an engine, a leakdown test should be performed.

Previous Thread
Index
Next Thread

© 1998-2022 OUTDOOR SITES NETWORK all rights reserved USA and Worldwide
Powered by UBB.threads™ PHP Forum Software 7.7.3