View Full Version : Info on 1994 Force 90

04-29-2009, 07:15 PM
"Any one got one of these engines? Would like to know of any dealings with this motor as I have just bought one to replace my worn out johnson 70 on my pontoon boat,would like to hear from anyone, good or bad & what little quirks to look for."

05-01-2009, 10:30 PM
"Scotty, I am not totally against the engines, but personally would have bought almost anything else except a Force.

A little history. When Chrysler marine was going bankrupt in the early 1980's, the outboard division was bought out by Bayliner.

For a year or so they marketed them under their own US Marine brand name.

Then Brunswick (Mercury's parent company) bought out Bayliner and gave the Force line to Merc who continued to market them well into the late 90's as a lower cost alternative to the major brands.

Their attraction was the fact that they often sold for 30% or more less than a comparable Merc or OMC at the time.

They kept the production cost down by using up obsolete parts to build them.

So your "94" model has carbs that Merc stopped using on their own models in the late 70's and a Prestolite ignition system that wasn't seen on anything other than Chrysler's (that hadn't been built for over 10 years when your model hit the showroom).

Various other parts were cobbled together to make a complete outboard.

Now, to be fair, my buddy has a 1990, 90 horse. We just rebuilt it last year. At the time it had well over 2000 hours of run time. Prior to the rebuild only a single coil and a starter had been replaced - however, it had been meticulously taken care of over it's lifespan.

In general I like the way the motor runs - it's an ok motor - it just happens to be built with technology up to 20 years older than the model year of the motor..."

05-02-2009, 11:02 AM
"Graham, I got this engine for 900.00 bucks & That was including getting it rigged on the boat, thats really the only reason I bought it other than the fact that my johnson died on me. Had to have something quick. I 've heard of some problems with the prestolite ignition, can it be replaced with something else? Does this model basicly have merc electronics or is it a pull apart & see whats there?"

05-03-2009, 01:03 AM
"The ignition is traditional Chrysler, the carbs are old Merc Tillotson's - they leak like crazy when you tilt the motor up (but I believe they could be replaced more modern Walbro's) , the rest kinda depends on the actual model number of the motor.

In some model years there were over 50 different models of the same horsepower - cobbled together with whatever was in the warehouse.

I have often thought that with a bit of fiddling around that a Thunderbolt 4 ignition from a 75 or 90 horse Merc could be retrofit, but I've never got around to trying that, plus, unless you were kinda doing it from parts laying around the process could be very expensive.

The Prestolite system is fine when it works, but can be a bit of a pain to trouble shoot - if it's working enjoy the motor.

On a positive note, CDI has all the ignition components, superior quality to OEM and for about half the price Merc charges, should you ever need parts.

It does however, sound like you got a decent deal. Force takes alot of bashing but they were a half decent "budget" motor and if taken care of can last quite a while.

In the end a running Force is better than a Merc or an OMC that is sitting in the scrap heap "

05-05-2009, 01:17 AM
"Graham, have'nt gotten my pontoon back from the shop yet, still getting rigged up. Do you think there will be any difference as far as speed between the 90 force & the 70 Johnson that was on it? Also I got a 30 day warranty on it so I plan on running the snot out of it for a few days, not abuse it but you get the idea. The way I understand it they are rated differently on horsepower, Force @ the powerhead, OMC @ the prop. one guy told me that the johnson would be faster. I just want it to run with as little trouble as possible. But with all the negatives that i've heard I'm beginning to think I should have researched this a little further before I bought it but it's mine now @ I just hope I get lucky @ it's a good one. Thanks for the info @ the help. I may have to pick your brain in the future on this. Thanks, Scotty"

05-05-2009, 09:14 AM
"Scotty relax!
The fact that it is still running after 15 years shows it is not all doom and gloom with force motors. The positive with old technology is that it is easy to work on! There are tons of parts to be found esp. on line and on this web site. Just make sure the water pump is working properly, change the gear oil every season, give it fresh plugs every few months(2 cycle can foul them, and I like champion,its what the original manual reccomends) And most importantly, enjoy.....till it craps out


05-05-2009, 10:15 AM
"Scotty, the 90 Force does have more power than the 70 OMC.

All have been rated at the prop since the mid 80's.

And as Mauro points out, sometimes the old technology is positive. The one that we rebuilt last year had quite a bit of "meat" in the cylinder walls.

Due to the damage on one cylinder (broke a piston ring) had it bored out .030" over. The guy at the machine shop said there was still "lots left" which would allow a second bore if necessary.

That 19 year old Force 90 is running like new again and every bit as powerful as a 90 Merc/EV or anything else.

And the good part is, if you really wanted something else, with a couple cans of spray paint and a new set of decals, you can have a Merc or an Ev or a Johnson

Enjoy the motor, they really are ok."

05-05-2009, 06:37 PM
"Thanks guys. It will be memorial weekend before I get to run the engine due to changing work schedules but I'll let you know how it does. It's just nice to know that there are people around like you guys that are willing to help with a problem should one arise, I do appreciate all the comments & thanks again! http://www.marineengine.com/discus/clipart/sun.gif"

05-25-2009, 11:48 PM
"Well guys, My Force experience isn't starting off very well. When I got back from vacation the marina that I bought it from said it was ready to go. I didn't even make it out into the river before it dropped a cylinder, #2. But it runs pretty darn good for a 2 cylinder 90 horse. I never could get it to pick it back up so now it's up to the marina mechanic to fix it as I have a 30 day warranty on it so I'll keep you posted on any disturbence in the Force!!! http://www.marineengine.com/discus/clipart/uhoh.gif"

05-26-2009, 11:34 AM
"If I was a betting man I would say they will replace a coil and play around for a while, then try swapping out a CDI pack and still scratch their heads before they finally replace the trigger which has a weird habit of only losing the pulse for the number 2 cylinder but tests good when you are checking it.

Not that "I" have ever seen that on a 90 Force before "

05-26-2009, 03:05 PM
"Thanks, Graham I'll check with them today & see what they have tried to do it. I know they were going to replace the coil on it to see if that worked & I haven't heard from them as of 2:00 pm today so I guess they are still scratching their heads over it. I'll pass along your suggestion & see what happens. Thanks again for all your help, Scottyhttp://www.marineengine.com/discus/clipart/light_bulb.gif"

06-05-2009, 09:27 PM
"Hey Graham, Guess what? I got a call from the dealer today & You will never guess what all they did, replaced every part that you said they would before they figured it out. I made a suggestion that it might be the trigger but they said it was good,HA! I get to try it out tommorrow so I'll let you know how it turns out. They might want to give you a call next time they can't get it right. I know who to ask!!! Thanks. Scottyhttp://www.marineengine.com/discus/clipart/biggrin.gif"

06-05-2009, 09:36 PM
"Scotty, I'm not any smarter or better than the techs, but after you have spent 3 or 4 days chasing your tail on one of these prestolite ignitions you never forget what the problem was "

06-06-2009, 10:31 PM
"Well, today's outing didn't go so well. There is definitely an improvement & it's firing on all 3 cyls but it sounds like you are tapping out a morse code message the way it is missing. I called the dealer & told him what it was doing & he couldn't believe it. He said they had just put it in the slip about an hour before I ran it & it was running fine, so now we are back to square 1 & going back to the shop. It now has new coils,wires, plugs,CDI ingnition & a new trigger. Might be a carb issue as they rebuilt them to start with after I told them that I wanted the engine.http://www.marineengine.com/discus/clipart/question.gif"

06-07-2009, 05:12 PM
"You certain they put in a NEW trigger - that still sounds like a trigger problem on this model.

The OEM triggers have very very fine wires, barely thicker than 5 or 6 strands of human hair and the little connectors on the end of them that go on the terminal strip can break sometimes if you look at them too hard. They are the 6 little wires (2 per cylinder) on the extreme right end of the strip (take the last 6 terminals).

CDI/Rapier makes a far superior trigger for this model and it costs less than 1/2 of what Merc wants. It's desinged so that only 1 single "thick" wire replaces the 2 per cylinder on the OEM trigger - works great.

Might suggest that to the shop after they spend 4 more days fiddling with the motor "

06-07-2009, 11:42 PM
"Graham, I'll check with them monday, I had to work today but a buddy of mine said they were working on it today @ the marina after they brought his boat back from the shop. And I forgot to mention that the idle was higher after I tried to run it the other day & it's really idling a little too high but I didn't mess with it much, didn't want them saying I screwed it up, but I'm not totally dumb when it comes to engines. I could fix my old johnson just about every time anything went wrong with it excecpt a busted block. I build my own engines for my race car so I guess that qualifies me to know enough to be dangerous, Ha,Ha!! Really I can't say it enough thanks for your advice.http://www.marineengine.com/discus/clipart/happy.gif"

06-08-2009, 05:31 PM
"I forgot the dealer was closed today, so I piddled with it for a while. I think the carbs are a little out of sync, after you run the engine for about 15 minutes then hesd back into the marina it idles higher than when you first start it up. And the miss is definitly electrical, but I'll find out in the morning if they put a new or used trigger on it. I'm thinking used cause they have a parts motor out back. They told me that the ignition was a CDI & it looked like the stator had been replaced so I'll just wait & see.http://www.marineengine.com/discus/clipart/biggrin.gif"

06-09-2009, 05:11 PM
"I talked to mechanic today & he said that the trigger was rebuilt CDI. They are going to work on it tomorrow. He thought that it could be a bad trigger as they had same trouble with a johnson recently. The miss was worse @ WOT than @ 1/2 or 3/4 throttle but still there. Had pretty decent power even with a miss, think I'll like it if they ever get it right.http://www.marineengine.com/discus/clipart/happy.gif"

06-15-2009, 12:05 AM
"Well it looks like they got the missing problems worked out, runs real good in the river, just getting out of the marina to the river is the problem. It doesn't want to run very well at idle or just a little above it. It smokes like hell when you start it up & you can see a haze behind you. The carbs were rebuilt before I got it but they aren't quite right. They are going to check it out monday to make sure compression is in spec & work on the carbs. but it ran well on my boat going down the river so maybe they will get those tillitsons to work properly.http://www.marineengine.com/discus/clipart/biggrin.gif"

06-21-2009, 11:08 PM
"Well They seem to have got the ole Force running like it should. I ran it this weekend without a hitch. Wasn't the perfect idle but it will do. It pushes my 28 ft Harris pretty good & it runs smooth down the river at various speeds without any problems. If you ever in the Parsons, TN area check with Dotties Marine They will do what they say. They probably didn't make a nickel on this one after all was said & done but they are good folks. Graham, If you read this thanks again for all your advice. I may have to ask something again sometime,& your input was much appreciated. Happy Boating to all!!http://www.marineengine.com/discus/clipart/happy.gif"

10-08-2018, 01:38 PM
Does anyone know where I can find a digital copy of this manual, or by a paper copy in general? Seriously considering buying a boat with a '94 Force 90 on it.

10-09-2018, 04:48 AM
E-bay is a good bet for manuals.
This post's 9 years old, they don't like it if you wake up the dead :)

The 94 is a good motor, easy to work on and fairly dependable.
In 94/95 they switched to a lot of Mercury components.
Post the model # for the right answers to future questions.

Depending on the model# you can use possibly a 92-94 manual and maybe a 1995 manual???

10-09-2018, 09:10 AM
Thanks for the response Jerry, after I posted I noticed in other threads that some people like to complain about reviving old threads. I'm not here to step on anyone's toes, but to me more threads mean more clutter.
1 - There should not be a problem with anyone posting on an older thread if the question is relevant, if someone doesn't like it they can choose not to answer.
2 - If they don't want to receive notifications that someone has posted on a thread they're no longer interested in they should unsubscribe or adjust their notification settings.
3 - If it's an official policy, then moderator's need to freeze threads when they reach a certain age. If it's not a policy, and they aren't a moderator, they can keep their sour attitudes to themselves.
Sorry for the opinion piece, but if people don't cater to the complaints then it won't be the status quo. The whole point of a public forum like this is for people to share information, people tend to lose site that occasionally.

I appreciate the info you shared, and will start with the actual model number when I get it. Thank you!