Low compression on two cylinders

mppd20

Recruit
Joined
Jun 7, 2009
Messages
1
I look at an 89 Maxum today with a 125 Force O/B. Owner said he had it out and ran great and then started to miss. I now know I did the compression test wrong, but the motor cranked fast and slow when trying to start it. That was my first clue maybe problems. I checked each cylinder one by one and left the plugs in the other so maybe that was the problem but my results were 1 - 25lb / 2 - 100lb / 3 - 100lb / 4 - 25lb. Battery was not fully charged, am I looking at problems or errors on my part?
 

pckeen

Commander
Joined
Jun 20, 2012
Messages
2,067
Check with a different Guage just to be sure, but those numbers indicate your heads need to be rebuilt. Those Force OBs don't have the best reputation. If I were you I wounderstand be looking for abother OB.
 

Jiggz

Captain
Joined
Oct 23, 2009
Messages
3,909
Do the compression again so as to have a better confidence with your readings. Remove all plugs while doing this. Even better, spray WD40 in each plug hole before testing.

However, looking at the previous readings, I would surmised the low readings indicate some problems either with broken rings or at the minimum broken head gasket.
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
18,125
Don't use wd until the test is done.
​Make sure the battery is hot and ground the plugs if your gonna use the key to do the test.

After first test, then spray wd in the cylinders and see if the comp readings come up.
Post the results of both tests.

Maybe just a bad gasket??

pckeen you don't know what your talking about!!
There are a lot of Force fans here.

The Force/ Chrysler is a good running motor that gets a bad rap from people like you who don't know what they are talking about.
If you read the post you'd know he did the test wrong and the readings he got weren't the right ones.
ANY motor when taken care of will last a long time.
Makes no difference of the brand.

Usually the failure of a motor results in the lack of maint or upkeep on the owners part.
My neighbors 2 of them. Both didn't do the basic flushing the Yamahas and any motor requires.
The one neighbor spent $600 the other $500 to fix.
It's not the motor brand but the OWNER.
Go "help" on another forum.
 

pckeen

Commander
Joined
Jun 20, 2012
Messages
2,067
The OPs comment was that he was looking at this boat. I've owned a couple of Chryslers in the past (one was great). Given that the OP may not have bought it yet, it's worth being cautious, particularly when there are a lot of boats out there, looking for new owners. I'm sure there are lots of fans, but unfortunately, with Force and Chrysler no longer producing outboards, this brand has more than its fair share of detractors.

OP - if you are deciding whether to buy this, do a google search for "history of force motors," you'll find a lot of comments about this motor - and you can decide for yourself.
 
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