Force 120HP 1994 - Advice Needed in Ireland

Hi Everyone.
I bought a 1994 Bayliner Capri 1700 LS Bowrider with a Force 120HP early this year.
Because it had been sitting in a shed for quite some time, and didn't have a paperwork service history, I thought it best to strip the engine and replace the P-Rings and seals.

I am having a tough time getting any information about the engine. Heck, even buying a part or a manual is OK, but the shipping charges from the USA are ridiculous!!!. A $20 Manual costs another $50 to post!

Anyway. I'm hoping that some of you experienced and knowledgeable chaps in the forum can point me in the right direction.

1. TACHOMETER: In order to optimise my propeller selection, I need to know my revs. Can anybody confirm if the 1994 Force 120HP is a 20 or 12 cycle Tacho?

2. Ventiliation / Cavitation and Handling: I operated the boat for about 5 weeks over the summer. I think these symptoms are related, so hopefully someone can provide advice.
Ventilation Plate about 1" above the lowest point of the "V" at the stern.
When stationary, steering is neutral. When in forward motion, easy to turn to the Right, VERY stiff to turn to the left. ( I haven't had a chance to adjust the vertical trim tab yet).
When turning, I frequently get Ventilation / cavitation, but not always?

3. Gearbox.
When we launched the boat, when transitioning from Forward back to Neutral, I would get a rattling noise, like gear noise. The noise would disappear under torque (when under any throttle) My mechanic friend was convinced that the problem was STIFF GEAR/THROTTLE CABLE. After a few days usage on the water over the following month, I noticed that the Gear Rattle was more prominent, and became noticeable even in forward gear and under torque. Successively, the rattle would be more prominent even at higher revs, until it got to the stage where the rattle would stop only under full throttle. At this stage I stopped using the boat and took her out of the water before I did some major damage.

If anyone can shed some light on these topics, I would be most grateful.

Also, does anyone know where I can get an Electronic (PDF) copy of the Service/Workshop Manual rather than pay silly shipping charges?

Regards
Irish Dave

Re: Force 120HP 1994 - Advice Needed in Ireland

1. TACHOMETER: In order to optimise my propeller selection, I need to know my revs. Can anybody confirm if the 1994 Force 120HP is a 20 or 12 cycle Tacho?
If it is indeed a 1994 120HP, you need a 12 pole tach. If your ignition system uses the Mercury switch box ignition system, that would confirm the 12 pole tach.

2. Ventiliation / Cavitation and Handling: I operated the boat for about 5 weeks over the summer. I think these symptoms are related, so hopefully someone can provide advice.
Ventilation Plate about 1" above the lowest point of the "V" at the stern.
When stationary, steering is neutral. When in forward motion, easy to turn to the Right, VERY stiff to turn to the left. ( I haven't had a chance to adjust the vertical trim tab yet).
When turning, I frequently get Ventilation / cavitation, but not always?
Stiff turning to the left is common, however, it should not be excessive. Adjusting the exhaust snout which acts as the trim tab minimizes this effect. Ventilation/cavitation usually means that the prop is too close to the surface of the water. This is more likely to occur when turning as opposed to going straight. If the motor is trimmed all the way down, then the motor may be mounted a tad too high. When I'm cruising along at a pretty good clip, I usually trim my motor up. Sometimes I can hear the prop ventilate/cavitate (not sure about the proper term here) when I make a turn. Trimming the motor down just a tad eliminates this condition, so I think that if you can get your motor down just a little lower, you might be able to eliminate this too.

3. Gearbox.
When we launched the boat, when transitioning from Forward back to Neutral, I would get a rattling noise, like gear noise. The noise would disappear under torque (when under any throttle) My mechanic friend was convinced that the problem was STIFF GEAR/THROTTLE CABLE. After a few days usage on the water over the following month, I noticed that the Gear Rattle was more prominent, and became noticeable even in forward gear and under torque. Successively, the rattle would be more prominent even at higher revs, until it got to the stage where the rattle would stop only under full throttle. At this stage I stopped using the boat and took her out of the water before I did some major damage.
Sounds like either the gear shift linkage may need to be adjusted so that it is more biased towards forward, or the teeth on the clutch dog inside the gearcase may be starting to get rounded off and no longer staying engaged. Might try draining the gearcase oil and inspecting it for metal flakes. Be sure to avoid removing the gear shift pivot pin which may look like the drain plug. Most of the time, dis-assembly of the gear case is required to get the pin back in.

Re: Force 120HP 1994 - Advice Needed in Ireland

Additional pointer about the gearbox, make sure when you shift you DO NOT EASE IN the lever but instead be a little snappy. This will ensure the clutch dogs always fully engage during shifting and preventing premature wear. but if the problem persists, adjust the shifter are previously mentioned to put a little bias forward.

Re: Force 120HP 1994 - Advice Needed in Ireland

Post a pic of the electronics on the stbd side of the motor.
You 94 came with either the Prestolite or Mercury ignition.
Pics and a serial # will help.

Re: Force 120HP 1994 - Advice Needed in Ireland

Thanks for the prompt replys Guys. Appreciate it.

Engine Number is 0E064809. Seems to be an early 1994 build, but I haven't found the Model Number on it....yet!.

The transom holes do provide me with 1 more step to lower the engine by about 1". Having read another thread about water spilling over the transom, I wull check that the Splash Plate will still be above the waterline, and if so I will drop her down 1".

PNWBOAT. I will check the switch box ignition and verify if it is Mercury or not. Thanks for the reply. I was convinced from reading anything I could find on the internet that it would be a 20 pole. 12 pole gives much more options. Thanks.:joyous:

Re: Force 120HP 1994 - Advice Needed in Ireland

Just to further clarify which ignition system you have.

If you have this type of ignition system that has two sky blue CD Modules (item#8) and 4 sky blue ignition coils (item #20), then you need a 20 pole tach.

Mercury, Mercruiser, Force, etc. - IGNITION COMPONENTS (90A,91C) - 120 H.P.


If you have the switch box (item #13), and four very dark blue...almost black looking ignition coils (item #27), then you need a 12 pole tach.

Mercury, Mercruiser, Force, etc. - IGNITION COMPONENTS (91D,92C) - 120 H.P.

If you are still unsure, then like Jerry mentioned, post a picture of the ignition components and we can verify.

Re: Force 120HP 1994 - Advice Needed in Ireland

Looks like the 91D,92C version.


Does this Voltage Regulator look Toasted, or is this normal?

also, can you tell me what might have been mounted onto the lower Right Hand corner of the mounting plate?

Re: Force 120HP 1994 - Advice Needed in Ireland

That's the Mercury 12 pole.
The motor came with 2 different Mercury Stators.
One's red the other's black.
Not sure it will make the difference in buying a tach??
But it might be needed if you ever need to buy another.

Re: Force 120HP 1994 - Advice Needed in Ireland

Like Jerry stated, definitely a 12 pole stator. You have the red stator which seems to have a lower failure rate than the black version.

The mounting point on the lower right hand corner is a spot for a ground wire that goes from the mounting plate to the engine block. That's why there is no paint on that spot. Looks like you've got one already located kind of in the center of the mounting plate. I believe there was a service bulletin that recommended adding a second ground wire. You could use the spot on the lower right hand corner to do that if you want to. That wire connects the main ground reference point for the coils and switch box for the ignition system.

The burnt look of the voltage regulator is pretty much normal from what I've seen on that particular type. If you look at the bullet connectors on the two yellow wires that connect the voltage regulator to the wiring harness, you'll probably see that they're burnt looking as well. The connectors are located behind the mounting plate. You can check the voltage regulator by measuring the DC voltage between the red wire on the regulator and engine ground. should be 13.5 - 14.5 VDC at 2000+ RPMs.

Re: Force 120HP 1994 - Advice Needed in Ireland

Thanks pnwboat and Jerry.
Seriously grateful for your input.