How to test a Mercury Force 120 without starter

[johnkbl]

Hello!

I found a Mercury Force 120 1999 outboard, and it has a burned starter. (That was what the owner said). The owner also said that the engine has only 90 hours of use and has never been used in saltwater. If the starter is the only problem the engine has, it will be a good deal for me. I am ignorant in how to test the general state of the engine. Ofcourse a visual inspection will give me a lot of information. I dont want to buy the motor, replace the starter, and then, find that something else is wrong.

Could anyone here tell me how to check if the engine is OK without buying a new starter just to check it?

Thanks!!!

 

[johnkbl]

Re: How to test a Mercury Force 120 without starter

I forgot to say that the engine is located about 150 miles from my home.... So, I dont have a lot of time and resources there.

Sometimes I think that I like deals with problems... but.... damn! it is fun!!

Thanks guys!!

 

[jimg984]

Re: How to test a Mercury Force 120 without starter

if the starter is burnt out after 90 hrs... he must have used the starter has a trolling motor... beware!! cant tell much about a motor without a starter to crank it over (i'm sure know that)

 

[JB]

Re: How to test a Mercury Force 120 without starter

Betcha the starter is okay and he has bad wiring/connections to it.

Definitely worth looking at, but unless you can turn it over there isn't much you can do to test it.

It is not a Mercury. It is a Force. It cannot be demonstrated, even on muffs.

That means don't spend much on it. I wouldn't offer over a couple hundred for it as is.

 

[lowkee]

Re: How to test a Mercury Force 120 without starter

Starters don't cost THAT much. I'm always leary of a guy who doesn't replace a part that will drastically affect the price of what he is selling. I see it as a way to say "runs perfect, but oops, I forgot the keys.. you'll just have to trust me.."

 

[cdnfthree2]

Re: How to test a Mercury Force 120 without starter

And since boat motors aren't operated in a dirty dusty environment, the best cleanest motors visually could actually be the worst pieces of junk around. Visual inspections don't always tell as much as youd like with an outboard.

 

[Frank Acampora]

Re: How to test a Mercury Force 120 without starter

Remove the plugs and turn the flywheel by hand. If it turns easy, the engine is not locked up or grinding anything. Next, put you thumb over each plug hole while turning the flywheel. If it doesn't blow your thumb off, then there is no compression and the engine needs an overhaul.

If it does blow your thumb off, At least you know it has SOME compression. Thus, it may be acceptable mechanically. If it goes into and out of gear, and the prop turns, at least you know the lower unit is free. BUT remember that even well worn dog clutches will lock up and you will not be able to make them pop out of gear by hand.

Since you can not crank the engine, you can not assess the spark on each cylinder. While ignition parts are fairly expensive, they are easy to install and thus become a bargaining chip in price.

HOWEVER: If the engine can not be cranked and started, then you must buy it as a parts engine--depending upon condition maybe up to 300 bucks or so. And in making your decision, don't forget to factor in what gas is going to cost to look at it and bring it home.

BUT LIKE YOU SAID: It can be fun.

 

[johnkbl]

Re: How to test a Mercury Force 120 without starter

hey Frank!!!!!! great explanation!!!!!

i will check this engine maybe this weekend. i will try to get a leakdown tester and test the engine with a compressor..... but... that would be the first leak down test i have ever made.

also, i think that I can try to crank the engine connecting in some way a drill to the flywheel or to the propeller shaft. Yes, it is a crazy idea, but maybe it will work. If I survive to that experiment, will tell you about it.

the engine price is about 600, the starter here costs about 200. (i dont live in usa, have to pay shipping and a lot of taxes).

Thanks again.... more answers are always welcome!!!

 

[Bigprairie1]

Re: How to test a Mercury Force 120 without starter

I'm not too sure about this (Frank or RR might know) but that flywheel might have a pull start capability on the flywheel. Not that I would ever want to actually try to start it that way). Anyhow, if it does, take a friend with you and see if you can get some heavy cord and a handle and try to give it a compression test via a pullstart. Again, I'm just spitballing here but it may be possible in lieu of there not being an operative starter on it.
BP

 

[bman1bpm]

Re: How to test a Mercury Force 120 without starter

You could hook some jumper cables up to your car battery can hook the negative up to the outboard block and tap the positive to the starter's positive lead. This would at least check to see if the starter works.
I'd think that its wiring too, either that or it has a lot more than 90 hours on it.
Either way, I wouldn't pay $600 for a motor that isn't running

 

[Frank Acampora]

Re: How to test a Mercury Force 120 without starter

You can wrap a rope around the flywheel, but if the engine is not on the boat, you will move it rather than actually try to start it. Even if it is on the boat, while a good running engine can be pull started, one that has not run in some time will most likely just pull your arm out and tire you without starting.

Where is not in the USA? Canada?

Like Robin Williams said in his stand-up routine, "Canada is like the loft over a really great party."

 

[swick]

Re: How to test a Mercury Force 120 without starter

I know that this is an old post, but I'm adding this info for anyone who may come across it. Yes the 1999 Force was owned by Mercury. It was also the last year of the Force. I view it like Ford & Jaguar. Ford bought Jag and did some refining that was great for the car, but made no profit so they sold it. Mercury and Force had the same relationship. There is a big difference between a Chrysler Force and a Mercury Force, especially the 99, being the latest model.

Also, the 99 120hp does have notches on the flywheel to tie onto for a pull start. I'm experimenting with this myself because I just burned out my starter. I know that it is sometimes easier to start an engine leaving one spark plug out, I've done that before, and I believe it will be a hell of a lot easier pull starting a 120 if its missing a plug. Try leaving all 4 in first and give it a shot though.

Also, $200 for a starter is highway robbery. I got one off ebay last year for less than $90 with a one year warranty that hopefully I will cash in on. Otherwise rebuilding it should not be extremely difficult.

Lastly, I bought my boat with this motor on it, having read lots of negativity about the Force prior, I have to say, what an easy motor to work on. After a year of tinkering I can only say that my respect has grown for this particular engine, a year ago I was an amateur, this year I have a pretty good running engine. I'm going to put another cheap starter on it and drive it til it don't drive no more. Then I will troll home and sell it for parts. In the meantime I'm having fun.

 

[Banditz]

Re: How to test a Mercury Force 120 without starter

Yeah its old., but I gotta say...if you can pull start a 120hp motor, I for one am not messing with you!