1990 Force 120HP #2 Cyl zero compression and upon opening piston shows damage

[gica]

Ok after adjusting the cables by the manual I started both engines I get water through the top little bolt that I will use for tail tell.
The problem is if I adjusted the idle screw below 1500 RPM(on the dash reading could be more or less) they both die.
So again there has to be an adjustment issue here even though I opened all and cleaned all 4 carbs. Got to check idle with timing gun even though the RPM gauges are new I don't trust them. So look at the picture. Does that look right? I thought the idle screw is supposed to lift the throttle bar. It's not even close to it.

 

[The Force power]

Ok after adjusting the cables by the manual I started both engines I get water through the top little bolt that I will use for tail tell.
The problem is if I adjusted the idle screw below 1500 RPM(on the dash reading could be more or less) they both die.
So again there has to be an adjustment issue here even though I opened all and cleaned all 4 carbs. Got to check idle with timing gun even though the RPM gauges are new I don't trust them. So look at the picture. Does that look right? I thought the idle screw is supposed to lift the throttle bar. It's not even close to it.

Ok after adjusting the cables by the manual I started both engines I get water through the top little bolt that I will use for tail tell.
The problem is if I adjusted the idle screw below 1500 RPM(on the dash reading could be more or less) they both die.
So again there has to be an adjustment issue here even though I opened all and cleaned all 4 carbs. Got to check idle with timing gun even though the RPM gauges are new I don't trust them. So look at the picture. Does that look right? I thought the idle screw is supposed to lift the throttle bar. It's not even close to it.

Check with a tiny tach.
Also are these steps followed?
1.Disconnect the ball link to the carb cam at the timing tower. Disconnecting at the cam risks bending the cam. Move the cam away from the carb roller.
2. Loosen the screw(s) on the aluminum tie bar and let all carbs close completely, then tighten again.
3. Set the cam so that the scribed line is pointing directly at the black roller on the carb lever. If the cam has two closely spaced lines, set the black roller directly between them.
4. The black roller is held with an offset screw and nut. Loosen the nut and turn the screw until the black roller JUST touches the cam. ( OR SLIGHTLY EVER SO SLIGHTLY MORE ) Tighten the nut and re-attach the ball link maintaining the scribed line at the roller.

 

[gica]

Wanted to ask I set the cranking timimg at 28BTDC. Mine is a 1990 Force 120. I am going based on the book. Some have 30 but I think mine is at 28. Just double checking
Mine is Prestolite

 

[gica]

These are the flywheel timing marks

 

[gica]

Ok so cranking timing on Prestolite has to be set at 28 BTDC which I think I did. I will doublecheck tomorrow. And the 28 mark is the right one out of the 3.

 

[gica]

Ok so both engines were at 32 BTDC put them at 28.
Now the rebuilt engine I managed to get to 800 on muffs.
The other one I cannot get bellow 1000
And it oscilates like crazy above that.
Maybe there's an air leak. I mean it is old. I did change the head gasket already.

 

[gica]

I took the boat to a lake nearby today. The engine I rebuilt was the one with issues.
There was hardlyany gas coming on the transparent filter when squeezing the prime bulb. I took off the filter and it broke on one side but it was also nasty inside it looked like there was sand in it. I probably have to reopen the carbs and clean them.
The engine would start but die in gear. The other engine showed gas in the filter but at WOT it went to 6k RPM though it can be questionable and it did not go very fast. Probably 10 mph maybe 15. Are they supposed to run together to reach higer speed? Anyways the gas in the tank is a year old but it should be good. I used stabilizer 5 month ago. There are at least 70 gallons. I don't know how the oil mixture functions with theboat resting for this long?.

 

[gica]

My inline filter on the starboard side had sand in it. I could not prime or pull any gas to it

 

[gica]

Ok changed the filters and one prime bulb. One engine is great. The other has idle issues.
So maybe it is a new problem or it might have been there but just didn't notice.
I was having issues with the motor at idle and decided to check spark.
#1 has No spark, # 3 does.
It is not the coil I swapped coils and get spark on it on the 2nd engine.
So the 2 boxes on the right of the coils one controls 1 and 3 and the other for 2 and 4, could that be it or is there more testing to be done to make sure. Could the stator also be at fault. I know there is testing to determine but was hoping to see if it's something simple and clear like one of the control boxes. Thanks in advance

 

[gica]

Wanted to add that I just changed the rectifyer with the same kind that being the rectangular one with nuts for connections. The old one had a broken lead from ground screw to ground post. The other motor has the square one with black and 2 red wires plus yellow and gray. I do have 2 spare square ones, one with the black wire one without. I heard they are better than the other. I don't know if that would cause the #1 no spark issue. Again this is a 1990 120hp, B type motor. Just wanted to mention it. Thanks again for any advise.

 

[The Force power]

I was having issues with the motor at idle and decided to check spark.
#1 has No spark, # 3 does.
It is not the coil I swapped coils and get spark on it on the 2nd engine.
So the 2 boxes on the right of the coils one controls 1 and 3 and the other for 2 and 4, could that be it or is there more testing to be done to make sure. Could the stator also be at fault. I know there is testing to determine but was hoping to see if it's something simple and clear like one of the control boxes. Thanks in advance

Move the wire leading to coil #3 to #1 and see if it sparks?
IF it does; check the trigger-wires/connector for #1

 

[gica]

So unplug #1 and use the #3 lead wire in #1 for spark. I bought the DVA adapter and the spark gap tester. So as far as the trigger testing are there specific wires? Thanks.

 

[gica]

So ine of the 2 # 1 trigger wire came right off when pulled on.
Battery is low am charging it right now.
Switched the #3 and #1 leads but could not get visible spark from the low bat.

 

[gica]

So now I have no spark on any of the leads. I fixed 2 wires that came from the trigger. I tested by taking off the two yellows and no spark. Also the black and yellow at the rectifier. I am teying to find the tests for the stator and trigger with DVA adapter for 1990 model 120HP.
Also I removed the tachs because they were the 12 pole types. Can that causeissues when removed?
I did buy the Amazon 20pole tacks and on the back they are a bit different they have ignition ground and send. So I was thinking purple for ignition since it goes on and off with the key black to ground and gray/ black to the send post.

 

[The Force power]

So now I have no spark on any of the leads. I fixed 2 wires that came from the trigger. I tested by taking off the two yellows and no spark. Also the black and yellow at the rectifier. I am teying to find the tests for the stator and trigger with DVA adapter for 1990 model 120HP.
Also I removed the tachs because they were the 12 pole types. Can that causeissues when removed?
I did buy the Amazon 20pole tacks and on the back they are a bit different they have ignition ground and send. So I was thinking purple for ignition since it goes on and off with the key black to ground and gray/ black to the send post.

THE YELLOW WIRES going to the CDI-modules GENERATE THE POWER FOR THE SPARK, they NEED to be hooked-up
Make sure the kill-circuit is open/ not grounded
I send you a PM on how to check the ignition/Ohm readings etc etc.
I.....would change all the connectors on the trigger-wires/check condition of wires for breaks in them. they're very thin!
IF you have a 12 pole stator? (the 85/90 hp does) a 20 pole will not work

RE-check your hook-up of the wiring & make sure the starter spins fast enough to create the power for spark

 

[gica]

THE YELLOW WIRES going to the CDI-modules GENERATE THE POWER FOR THE SPARK, they NEED to be hooked-up
Make sure the kill-circuit is open/ not grounded
I send you a PM on how to check the ignition/Ohm readings etc etc.
I.....would change all the connectors on the trigger-wires/check condition of wires for breaks in them. they're very thin!
IF you have a 12 pole stator? (the 85/90 hp does) a 20 pole will not work

RE-check your hook-up of the wiring & make sure the starter spins fast enough to create the power for spark
View attachment 389373

Weird I could not get any spark on any of the spark testers, so after fixing the trigger wires for number one I put it all back and it started. I get spark on number one also. It doesn't look strong on the cheap tester, really faint red light. Maybe the daylight is causing the spark to not be so visible.
My stator is a 20 pole the tachs I bought from Furia don't show the right RPMs. So I just installed the ones from Amazon for 20 pole and one works the other does not. So I replaced the older style rectifier with the square one. Haven't tested it yet to see the tach is working now.
Ok just checked and 2nd tach up and running. The old style rectifier was junk.
So if the gray didn't get give signal the yellow that was linked to it aldo probably was not good. On the old rectifier one yellow is linked to the gray.

 

[gica]

So I did the cranking timing at 28BTDC. Is this ok as I read some go to 30BTDC to get a better idle? I could be wrong on what I remember reading but it did say most ignore the specs on the timing.

 

[gica]

Have a question on the stator, when I used the multimeter I noticed that the stator is charging differently that an alternator it is slow on building up the charge, at least on one engine it doesn't just jump up from 12.5 to 13.5 or so.The other one also is going upslowly but a bit faster than the first. They pretty much both slowly go up.
The picture shows the boat at wot 4500rpm and the gauges show one at 12 and the other closer to 12.5
This is before I fixed the wiring on one of the engines that did not hold idle.
Any idea if there is a problem with te stators or are they slow to charge? Thanks

 

[The Force power]

Have a question on the stator, when I used the multimeter I noticed that the stator is charging differently that an alternator it is slow on building up the charge, at least on one engine it doesn't just jump up from 12.5 to 13.5 or so.The other one also is going upslowly but a bit faster than the first. They pretty much both slowly go up.
The picture shows the boat at wot 4500rpm and the gauges show one at 12 and the other closer to 12.5
This is before I fixed the wiring on one of the engines that did not hold idle.
Any idea if there is a problem with te stators or are they slow to charge? Thanks

Hmmmm, output of the stator(s) maybe and/or condition(s) of batteries (may) vary

 

[racerone]

On most motors you would see 13.5 volts at fast idle.___What kind of battery in your system?