1999 force 120hp

hey guys. i have been killing myself over my engine for the past year. what started out being a exhaust cover problem, turned into being getting water into one of the cylanders forcing me into deciding to sell my boat. i have never worked on a marine engine before, but i am no dummy. i bought my boat for 8000 2 years ago, and got one year out of it. its been sitting since last november. should i attempt to work on this? maybe take it apart and bring the parts to a machine shop to get rebored (get new piston, or fatter rings) and get the head shaven? <br /><br />i know a lot of you guys know your stuff and have a lot of faith in the force motors. i love the motor (when it was running) <br /><br />im not sure what happened, but i did find out the guy before me didnt have a overheating alarm hooked up, and i knew nothing about it until now.<br /><br />sorry to write so much, but i really need some advice.<br /><br />thanks guys

Re: 1999 force 120hp

I have seen a run on 120hp forces taking water into the cyl's, with apperently good gaskets. I am looking into this problem to find out what is going on.<br /><br />As for your engine..its one of the good ones.<br /><br />TMD

Re: 1999 force 120hp

so should i start this project and maybe take pics i could post for advice form you guys? i would really like to try this myself. i would miss (as i am now) striper fishing with my older brother too much if i got rid of this boat.

Re: 1999 force 120hp

My opinion is that if you are somewhat mechanically inclined to tear into it yourself. You do need to isolate the reason water is getting into one of the cylinders. I had never worked on an outbaord until several years ago I needed rings in my 85 horse Merc. Did it by using a Clymer manual. It ran great for four years until I sold that boat. I did my stepfather's 65 horse Evinrude. Last project was a 100 hp Chrysler. It was by far the easiset to work on for me. You 120 is about the same as the Chrysler. I do have one bit of advice to offer being that when you put the piston/rod assembly back into the crankcase be very careful to closely watch the rod bearing surface and not nick it on the crankshaft. The unmachined area next to the journal is very sharp and I did put a nick in a rod like that which I replaced prior to finishing the job. Aside from that the job went very smoothly and I feel anyone with a good deal of mechanical aptitude can rebuild one of these engines fairly easily. That is one reason I have no misgivings about owning my Force 120. Good luck either way........

Re: 1999 force 120hp

It could be as simple as a head gasket.<br /><br />Or it could have been caused by an overheat, which could have done more damage.<br /><br />Tear into it, with manual in hand. And change out the water pump and impeller, and thermostat, since it is going to be 2 years (or more) old by the time it gets in the water again.<br /><br />Have you checked the compression yet?

Re: 1999 force 120hp

Ok school is in session : Your 1999 120 is an excellent engine and deserves to be put back together. A lot of times people mistake water in the cylinders for steaming of the exhaust which is caused by a bad exhaust gasket. another thing that happens that people dont realize not to get too detailed (cuz i can ) there is something called resonance affect which is basically sound waves coming from all two stroke engines they run back and forth, basically once your piston exhaust port is open this creates a low pressure area, if idling in the water or the boat is sitting low in the water, it can ingest a little water into the cylinder especially once the motor is shut off,but anyways what you should do, with the long block complete laying on a bench build yourself a test plate like we have in our shop that bolts to the bottom of your power head covering all intake and exhaust passages you will have to silicone this in place this plate will isolate your complete water passage. In the passage going to the water pick up you will drill and tap a 3/8 course hole install a pressure checker (we use the ones for the gear boxes) pump this up to 15lbs and let it sit over night it should not drop at all if it does it will be alot easier to find your leak. good luck, bret <br /><br /> If you need further assistance please email me @ forcepower01@yahoo.com. thanks,Bret

Re: 1999 force 120hp

force01, do you find that problem to be more common to the Force engines that are using the Mercury leg, the ones with the adapter? I wonder if its improper tuning of the exhaust that is causing the water problem?<br /><br />TMD

Re: 1999 force 120hp

TMD,<br />No, i see this on all the legs. its not very common but it does happen. Another phenomenon that exists as far as bringing water into the exhaust port is a broken reed. bret