1998 Force 120- Need opinion

[oscarjm]

People either tolerate or hate Force engines. I purchased a Tracker deck boat 2 years ago with a 1998 Force 120 HP outboard. Ran pretty good until a couple weeks ago; it would not idle and would only run at higher RPM. After spraying cleaner into the carbs and adjusting, I gave up and took it to a mechanic, as it was almost Labor Day weekend and I had lots of guests coming in for some boating.

He found a defective trigger assembly. $300 parts and labor.

He got it running again, but not for long. Turns out a fuel line hose had collapsed from the inside, and rubber pieces are in the carburetors. $300 parts and labor (not authorized yet).

The biggie: LOTS of water in 3 of the 4 cylinders. He thinks it has overheated through the years and the gaskets are worn. The previous owner disconnected the temp. alarm. $600 parts and labor.

Engine has decent compression for its age.

After I spend $1000, there is a potential that I have a cracked block, and/or, as I have read on these forums, potentially a cracked exhaust plate, common for this engine.

I can handle preventative maintenance on the engine (tuneups, water pump, etc). Unfortunately, I think I have the ability, but not the time, to tear into the engine myself. 2 small kids at home take a chunk of my time these days.

What would you do if this were your engine? Use the off-season to search for a used outboard, or bite the bullet and try to save this one?

 

[Jiggz]

These motors are really easy to maintain preventively and correctively as long as you are willing to learn and do the job. Having to have it done by a mechanic only has one advantage, he does the labor for you but other than that NOTHING! The advantage of you doing it are almost countless starting with saving $$, operating and maintainingly it correctly, knowing the job was done correctly and most of all diagnosing problems correctly.

Doing corrective maintenance sounds like it will take a lot of your time, but when you have all the help and learn how to do it, you will be surprised it takes very little time. For example, with my first OB motor, 125 HP, I replaced one of the pistons for a total time of less than 2 days. Sure them experienced ones can do it in less than half a day. But now with my acquired knowledge, I can do it in less than a day.

Some forum members who can barely turn a screw or know how to use a wrench have also done the same. I say keep the motor and learn how to operate and fix it. For starters, you need to post symptoms of the problem. The basic question is always, "What is it not doing that it is supposed to be doing and vice versa" Sometimes, the terms and parts names are challenging themselves, but you can easily learn this by getting yourself a maintenance manual and also going to boats dot net to see parts breakdown and their names.

Look at it this way, if you decide to rid of this motor and get a used outboard one, what is the likelihood you will be doing the same thing again in less than 2 yrs? Or maybe less than a 1 yr? Or maybe in a couple of months? While dumping $$$ along the way . . .

 

[NYBo]

Welcome to iboats!:welcome:

I agree with Jiggz. Although they seem intimidating, these motors aren't horribly difficult to work on. It also sounds like your mechanic is either not giving you good information, you are not understanding what he's telling you, or he's just throwing parts at the motor at your expense. Or possibly some combination of these. For example, $600 in parts and labor as an estimate when he hasn't determined what the problem is? The gaskets involved in a possible overheating situation don't get "worn". You stated the compression is decent; what are the actual numbers?

 

[oscarjm]

Thanks Jiggz. You are right about a different motor... I could run into the same problems and be out even more $. I guess where I am concerned is that I owned a 1984 60 HP Johnson that I bought from my dad, and in the 12 years I owned it, I only had to take it to the shop once for an electrical issue, so facing such extensive repairs is not something I'm used to.
It sounds like your advice is to fix what is broken (either by doing it myself, or by the mechanic). Pulling the powerhead isn't too difficult, and maybe I could bring it back home to work on during the off season. Worst case scenario, I don't have time and have to take it into a shop before boating season resumes. Thanks for the input!

 

[Jiggz]

Personally, I do not recommend taking it to a mechanic. Instead buy a maintenance manual and read through it to understand in general how it works. When you have a good understanding how it works, then it is time to tackle the specifics one at a time. Use this forum to expound and learn more. By having this knowledge, if you decide to take it to a mechanic you at least have knowledge of what he is talking about and at the same time having info on the parts and costs. But then, if you go one step further, you probably would just try to do the work yourself and saved $$$. Which you could just use to buy beer and relax to reward yourself.

Whenever you are ready to discuss the motor problem start a new thread and we will discuss it one at a time. Start first with your biggest concern and make sure you get the compression numbers from your mechanic and we will evaluate them if they are good or bad. With compression numbers, they are either good or bad and not decent or undecent.

 

[oscarjm]

Thanks again Jiggz and NYBo. I called the mechanic and asked a bunch of questions. First off- here are the compression numbers:

#1-160
#2- 165
#3- 170
#4- 160

According to the mechanic- cylinders 1, 2, and 3 were pooling water. #4 was fine. He said if he pulled the spark plug wire for #4, the engine would die, but wouldn't if he pulled the other wires instead. This tracks with what happened when I idled it up so it wouldnt' die, and sprayed in carb cleaner. Spraying cleaner in the top carb didn't kill the engine, but spraying in the bottom carb killed it, presumably because only #4 was firing properly.

He said he pulled the head gasket, but there was no evidence it was leaking (but that it wasn't real tight). This wouldn't cause pooling in the cylinders.

I mentioned the exhaust plate. He also said this wouldn't cause pooling in those cylinders in that manner, that it must be coming from the water jacket area. He said the only way to distinguish between bad gaskets and a bad block would be to replace the gaskets. If it is a bad block, he said good Force blocks are non-existent, and I would have to get a new or used motor.

Regarding "worn" gaskets, he said from the motor overheating and parts expanding and contracting, the gaskets might not be sealing properly anymore.

Let me know if you think his explanation checks out.

So here is exactly what happened before I took it into the shop. I went on a long 2 hour cruise, not at WOT, so the kids could nap. After the cruise, we stopped the boat for a few minutes so one of the kids could tube. Had trouble starting it back up. Primer bulb wasn't stiff, so thought that the hot engine was causing the fuel line to boil. Primed it, choked it, it started, but died when I put it in gear. Did this a few times until it would run. Went to WOT, and the boat stayed at idle for a while, then finally took off. It idled rough the rest of the day, and I had trouble getting it into gear without it dying. Took it out one more time, and the problem was more severe. Took probably 50 attempts to keep it running while shifting into gear. After trying to adjust the carbs, that is when I gave up.

I guess I'm wondering if the trigger assembly was really bad, or if I had a sudden failure in the block that caused the watered out cylinders. It seemed to run fine at WOT, it just wouldn't idle. The mechanic said I should have noticed a big power difference w/ only 1 good cylinder (and perhaps a couple more were firing at high speed), but I had the boat at capacity and chalked it up to that.

Lots of info above... bottom line is I'm taking your advice and will grab the boat and pull the powerhead to take home and work on. I bought a service manual after I got the boat. I'll definitely post under a seperate topic when I pull the powerhead and have questions. First job will be to replace the gaskets, if you agree that is where I should start. Thanks again... and I look forward to any more responses to the above!

 

[Jiggz]

"According to the mechanic- cylinders 1, 2, and 3 were pooling water. #4 was fine. He said if he pulled the spark plug wire for #4, the engine would die, but wouldn't if he pulled the other wires instead."

Even a novice OB mechanic will have a hard time believing in such diagnosis! Even with only two cylinders firing, you will have a very hard time starting such motor let alone idle and run, worse yet only on one cylinder!

"Pooling water" is obviously exaggeration to instill fear and persuade the customer. If any liquid pools in the cylinder the motor will go into "hydrolock" that even a strong electric starter or manual starter for that matter can turn it over.

What is not logical with the compression numbers is that they are too high even for a brand new motor. But then it could also be the gauge used. But if there is water leaking into 3 of the 4 cylinders, I would have expected lower compression numbers on the said cylinders. Unless, the said water is coming from the exhaust cover or plate.

If what he mentions, "He also said this wouldn't cause pooling in those cylinders in that manner, that it must be coming from the water jacket area . . ." is correct that means the compression numbers should be really low like below 100 PSI.

The bottom line, I believe the mechanic is out to take advantage of you.

Checking for water leaks is a piece of cake. All you need is a socket set, a torque wrench and a head gasket. You might not even need the gasket if after opening and inspecting it is found to be good still. However, if the compression numbers are good which I recommend you re-do (loan one from auto stores or buy one for less than $35). If you do not know how to do it, there is one on U-tube to show you how. With good compression numbers, there might not even be water in the cylinders or if there is you should be able to tell that with the spark plug or better yet remove spark plug and crank over the motor while putting a napkin in front of the plug hole to catch the air-fuel mixture. If there is water, you should see it in the napkin. And if there is water and compression is good, it's most likely coming from the exhaust plate.

Now if there is no water, then your problem is not water in the cylinder or low compression but most likely carburetion, fuel delivery, reeds or electrical. Electrical is easy to diagnose by getting an in-line spark tester from any auto store for less than $10. Test all cylinders and if they check out OK, then the problem is down to three major items, fuel delivery or carburetion and reeds. Fuel delivery is also easy to diagnose by installing a clear fuel filter (Fram G2 from walmart for less than $5) between the fuel pump outlet and the carbs' inlet. If it stays full all the time and during problems when the engine will not start or ran at WOT, then it means you have good fuel delivery and the problem is down to two, carburetion or reeds. And those 120's are well known to have fragile reeds they break more often than any other models.

 

[oscarjm]

Thanks again Jiggz. You are really giving me some confidence to figure this out myself. I have a compression gauge already that I used when inspecting the boat before purchase- think the numbers from my gauge were in the 140's, with #2 being lower than the others.

I've replaced the head on an old Jeep 4.0L and an Allis Chalmers WD45 tractor, but haven't completely torn apart an engine since junior high shop class... and that was a lawnmower. Guess its time to go step by step on this and figure things out.

I replaced the fuel filter this spring when I did the water impeller and pump. When this problem happened, it was definitely getting fuel, maybe to the point of flooding. I did notice a little moisture in the catch basin of the carburetors. I wasn't sure how it got there and whether the engine had gotten splashed with some water while I was looking at it.

Based on what you say, I'll check out how bad this water problem is with the napkin approach, cylinder by cylinder. Think I better tackle that first before proceeding further. I really hope its the exhaust plate. Thanks again!

 

[Jiggz]

As mentioned, redo the compression first and note the numbers. Connect the cooling water with muffs and try starting the motor for about two or three times. If it starts let is run for about a minute. Thereafter, stop and disconnect the cooling water. Pull plugs and inspect them for water. If water is visible or wetting is apparent, there is no need to beat around the bush. Instead go ahead and remove the head being careful to save the head gasket for two reasons; inspection to determine the source of water leaks and also if it's good can be re-used. Removing the head is a lot easier than a the Jeep since it doesn't have any cams or timing gear in it. It's just a plain head with plug holes and water jackets. Do a thorough inspection as to where the water is coming from. Take a digital camera with you and always take pics of things before disassembly so you will have reference during re-assembly. A tip for taking pics, always do a close up of the thing for clarity and also a not so close up so you can see reference from other parts of the motor. A good example if if I send you a close up pic of my right knee, you will never know if it is the right or left unless I send you a pic of both of my knees or at least the entire right leg.

And to get immediate and accurate response, try attaching pics of the parts involved. It makes communication really easy and direct.

Now in the preceding test, if there is no indication of water in the plugs and the compression numbers are good, within 10% of each other and above 90 psi, go ahead and check for sparks in each cylinder using the in-line spark tester and repost your results. These should be enough tasks for today. But finally, I understand you just recently replace the fuel filter, but the clear fuel filter is a totally different thing. I recommend buying it and installing it. In fact, the unit already comes with hose clamps and all you need is to cut the existing fuel hose from the fuel pump to the carb inlet and install it. It is more for troubleshooting than a filter.

 

[sportrider]

I say just dive into it, I recently went through this with my Force 125. I even screwed up and trashed a crankshaft and connecting rod. but after removing the powerhead buying a used crank & rod, a complete powerhead gasket set, bearings and seals, my 125 runs dang good! fires right up, idles good, and has more power then it did when I bought my boat. I know my boat and engine inside and out, and I got all this experience and education for the whopping cost of $486.00 and some of my time doing the work and asking questions on the forum.

GET HER DONE!!!

 

[oscarjm]

I picked up the boat this weekend and pulled the exhaust cover and plate, head, carburetors and reed blocks. Very easy. I'll make a new post with pics... hoping you guys might point anything I'm missing. Thanks for all the help!

 

[Jiggz]

Did you re-do the compression before doing so? Were they all good? What are the numbers? Was there actually water in any of the cylinders? If none, is there spark in all the cylinders? Why the tear down without diagnosis? What is wrong with the motor anyways? Idling?