Help With my New to me Force Motor

[canyonbrewer]

Hi All -

I just purchased a pontoon boat with this motor. Previous owner says it runs on 2 cylinders, but doesn't know what is wrong with 3rd. I have no idea what this means. He says he drove the motor with 2 cylinders. When I looked under the cowling, the bottom spark plug wire was unplugged.

Couple questions:

1. Can anyone help me identify the year of this motor? My guess is 1999.
2. Paperwork I have shows a number OE 362000. Is that a serial number?
3. Can someone point me to the correct manual(s) I should purchase to work on this motor?
4. Can anyone offer some basic initial troubleshooting? I plan on testing compression and spark in the next few days. Should I remove the head and try to determine what is wrong with the 3rd cylinder?

Serial number tag from motor was rubbed off and non visible.

Here are some pics:

Thanks for any help you can provide!

 

[Frank Acampora]

Re: Help With my New to me Force Motor

In the 1990s Mercury went to serial number system. This was to prevent dealers from needing to discount a year old or two year old new engine that never sold. However, these serial numbers do correspond to a year of production. If you need to order parts from a dealer, there is a range of numbers for which a certain part is available. Hope that clears that up.

Back to your problem: It really sounds suspicious. If the P.O was deliberately running it on two cylinders it sounds like something serious is wrong.

SO: before doing anything else, do a compression test on all three cylinders and report back with results. I would not be surprised if the bottom cylinder has 20 PS! or less, indicating a damaged piston.

 

[hbryant123]

Re: Help With my New to me Force Motor

Ide say definatly do a compression test, I bought a 17 foot rinker with a 85 hp force, it had a burnt top cylinder.

 

[roscoe]

Re: Help With my New to me Force Motor

Serial numbers OE345000 - OE369299 -- 1999

A factory service manual will be the most technically accurate and model specific. You can often find them on ebay.

But a generic Clymer Force repair manual will be cheaper and written more for the layperson.


Stay away from the Seloc Force manual.

 

[jerryjerry05]

Re: Help With my New to me Force Motor

No don't remove the head just yet. You might not need to.
After a compression/spark test, then you might need to take it off.
Make sure the air screws(screw with spring on the side of the carb) are all set at 1 turn out.
Fill out the profile,location??? You might be close to someone who can help.

 

[canyonbrewer]

Re: Help With my New to me Force Motor

Thank you all so much!!!! Really appreciate the expertise. Communities like this are amazing to me.

I will be checking the compression tomorrow, and will post back the results.

I will also update my profile....but the motor and I are just south of Charlotte, NC in Fort Mill, SC.

Thanks!

 

[Jiggz]

Re: Help With my New to me Force Motor

It does make a difference when you post pics of the problem. It's almost a trend when forum members see the pics, it give them a better idea what is being asked hence can respond sooner.

 

[canyonbrewer]

Re: Help With my New to me Force Motor

Ok All -

Just wanted to post an update....

I removed all the spark plugs yesterday and did the "dowel rod" test. Basically, stuck a piece of wood into each spark plug hole to feel the pistons moving as I manually turned the motor.

I could feel the top 2 moving, but I could not feel the bottom piston ever. My dowel rod wasn't very long, so i just assume the piston is sitting at the very bottom of it's travel. Or worse, destroyed in there.

This means rebuild right? Is it even worth it? Does anyone know what a rough cost to rebuild would be? NADA shows the value of the 1999 75 HP at $230.00

I guess I am just looking for confirmation that this thing needs to hit the dump.

Thanks!

 

[jerryjerry05]

Re: Help With my New to me Force Motor

Did it turn overwithout locking up?
Do a compression test.
The book shows one price but try to buy one at that price??? AIN"T gonna happen.
Those prices are for the dealer to screw you when you want to trade in.
Rebuild could start at $100 and go up.
1 piston and rings and a gasket kit start about $200???

 

[Jiggz]

Re: Help With my New to me Force Motor

With that kind of discovery personally, the next move is to remove the head and do a visual on the status of #3 cylinder. It's either the piston has been totally removed by the PO or the conn rod broke. Depending how much damage there is and how bad will determine rebuild costs. And you can't do that without opening and inspecting the unit first.