Force 125hp 1986 Odd Noise coming from engine.

[EricE]

I have a 1986 Force 125 hp. The motor starts right up but I am getting some unusual noise from the motor. The noise gets worse at higher speeds. I have good compression on all 4 cylinders and new plugs, however the motor is not timed.

Please watch the attached video. Make sure you have your volume turned up.

The noise seems to be a little louder near the #1 cylinder on the left side of engine (same side as starter).

Let me know what this sounds like to you.

Thanks in advance for your assistance.

 

[SkiDad]

Re: Force 125hp 1986 Odd Noise coming from engine.

I'm not an expert but it sounds like one of the cylinders sounds like it's not firing right. Have you tested with a spark tester on each ? How about a compression test ?

 

[EricE]

Re: Force 125hp 1986 Odd Noise coming from engine.

I've checked the compression and all 4 cylinders seem OK.

I'll pick up a spark tester. They come in 2 styles. One that lights up and one that you can calibrate the gap distance. I think I will get the adjustable kind so I can measure the strength of the spark.

The noise does seam intermittent. Sometimes I hear it, sometimes I don't. I did have bad corrosion so I replaced the boots and end caps on the plug wires. I may need to replace the entire plug wires. Do you know if they just screw in to the coil packs?

My main concern with the noise is the possibility that it is mechanical in nature... bearings, rings, bent or damaged reed valves.

 

[jerryjerry05]

Re: Force 125hp 1986 Odd Noise coming from engine.

What are the comp readings?? Just saying they "seem" ok isin't what we need?
Why do you say the "timed" you adjust anything? Change anything?
Timing usually won't change unless someone messes with it?
Do a static timing.Then a linc and sinc.
The coils, wires are part of the unit, no changing.
Run it after dark and see if the leads are shorting.Liquid electric tape,shrink wrap first.
The reeds usually don't make any noise,the gas will come shooting out the carbs if they are bad.
Plugs burning ok?No water?
Post compression #s. Seems ok isin't enough

 

[EricE]

Re: Force 125hp 1986 Odd Noise coming from engine.

I stopped by Advance Auto on the way home from work and picked up a spark tester. I got an adjustable spark tester so I could measure the spark length. The other kind of tester just lights up.

The compression on #1 - 125, #2 - 125, #3 - 126, #4 - 130
Spark length on #1 - .25", #2 - .5", #3 - .5", #4 - .5"

I cleaned the ground wires on all 4 coil packs, and main grounding wire from the mounting bracket and the engine block and various other connectors. I re-tested and still #1 was very weak compared to the other three. I ordered a new coil pack and will keep everyone posted as to the results.

In regards to the timing, the timing end control was cracked and the previous owner had zip ties holding it together. Had to replace it.
Here are some pictures of the spark tester.
#1


The other 3

 

[jerryjerry05]

Re: Force 125hp 1986 Odd Noise coming from engine.

Thanks for the comp#s.
The weak spark. Could be a bad coil? Try switching it around with a coil from the other end of the motor.
If it changes position?Then it's the coil.
If it doesn't change then move the packs around.If it changes position then it's the pack.
If it stays then I'd guess at this point?The stator.

Outboard ignition . com or CDI Ignition Both have test procedures for your motor.

 

[EricE]

Re: Force 125hp 1986 Odd Noise coming from engine.

Let this be a lesson to everyone... it cost me a 100 bucks. Be patient and wait for some responses from the experts. After diagnosing a weak spark on #1 cylinder, I instantly bought a coil from Crowley Marine for $104 where the same coil is less than $50 at CDI Ignitions... my first mistake. Secondly I swapped the #1 coil with the coil on #4 and the #1 cylinder still showed a weak spark. Crowley Marine has a no return policy on electronic parts so now I'm stuck with a coil that I don't need and even if I did need it, the coil received is a different design and I would have needed to make special brackets for it to fit into my mounting plate.

Taking Jerry's advice, I swapped the packs. It looked a little intimidating at first but swapping one wire at a time made it relatively easy. It fired right up and the weak spark jumped to #3. One pack controls #1 and #2 and the other pack controls #3 and #4 so the weak spark jumping from #1 to #3 makes sense.

While swapping some of the wires, the connectors broke off of the wires. I'm sure that replacing the weak connections should only help with performance, however I still have a weak spark on #3.

( This is a little off topic but hopefully others will get some benefit from my experience. I swapped my prop from a Stainless Steel 13.25 X 17 to a aluminum 13 X 19 and saw a dramatic improvement in performance. The 17 pitch allowed rpms to exceed 6000, the 19 pitch brought it down by about 500 rpm. I needed to run at 5200 rpm to maintain plane with the 17 and now I can maintain plane at 4200 rpm so now from 4200 to WOT is all top end speed.

The 1986 125hp force engine is spec'ed for a 13 x 19. The guy at the propeller shop said that he can re-pitch my Stainless Steel prop from a 17 to a 19 pitch.)

Looks like the pack is failing and a new one is quite expensive.
My questions are: Can you replace just one pack if it is not an exact match of the good pack or should both packs be exactly the same to avoid any potential compatibility issues.

Does anyone have a suggestion on where to get a used pack? My packs are black but I've seen quite a few that are blue on ebay. Is there a difference other than the color?

 

[labawg]

Re: Force 125hp 1986 Odd Noise coming from engine.

Not to take you farther off topic but whats the length of your boat? Fiberglass or aluminum? 17p SS on a 86 125hp Force turning over 6000rpm. Unless you have a 2to1 lower unit or a spunned prop thats very fast. Also I have a 1984 with Blue Packs and Coils. Your Black ones have plugs on them and most of the blue one are straight wires that teminate to a strip.

 

[Jiggz]

Re: Force 125hp 1986 Odd Noise coming from engine.

You might want to check back with CDIgnition and look at their two different styles of packs available and compare them to the ones on ebay. There is even installation sheet that comes with it which you can review before buying. As far as I know either blue or black will work with the 125's. I've seen other motors having both colors of packs installed.

 

[EricE]

Re: Force 125hp 1986 Odd Noise coming from engine.

My Boat is a 18.5 ft fiberglass center console that is built on a Bayliner Hull. I did ask the guy at the propeller shop about testing if the the hub could be spun and he said that I would definitely know if it is spun by the performance. One thing that I didn't know before is that a propeller shop can re-pitch a propeller. It is expensive, but if you have a Stainless Steel Prop, it would be less than half the cost of buying a new Stainless Steel prop.

I have questioned the accuracy of my tach. I don't know if the signal from the tach has anything to do with the #1 cylinder firing, however I could tell by the sound of the motor that the tach seemed to be behave erratically at times and read higher rpms. For example: I could advance the throttle a little and the tach could move from 4500 to 6200 rpms, the motor would speed up, however it did not sound like the motor just put on another 1700 rpms like the tach was indicating. Since this boat is new to me, I would adjust the throttle down to keep it cruising at about 5200 rpms because I was afraid of redlining the motor. At 5200 rpms I could maintain a decent plane, however it started falling off of plane just below 4800 rpms. I guess to get a true test is to put the SS 17 pitch prop back on (since I now get a good spark on #1) and check the results.

I can tell you that I tried several times to set the timing on the motor and could never see the marks. I even went as far as taking a black sharpie and coloring the side of the flywheel black and then taking whiteout and coloring the grooves of the timing marks to improve the contrast, however I still could not set the timing because I could not see the marks.

Since swapping the packs, I now have a strong spark on #1. It dawned on me that the timing light probably was not picking up the pulses consistently with a week spark on #1. Just to test my theory, I hooked up my timing light while idling with muffs in the driveway and for the first time I could see the timing marks on the flywheel. I plan on getting out on the water tomorrow and set the timing at WOT.

Frank made an excellent video on setting the timing and checking the carb linkages. Here is his video:

 

[jerryjerry05]

Re: Force 125hp 1986 Odd Noise coming from engine.

labawg,The black/blue were basically the same.Depending on the year of the motor?
The connectors depending on year can be the screw in type or the plug in ones.
The 84-86 were plugs and the rest were screw in.
If you have black packs with the plugs they were aftermarket made for the 84-86.
Any with the screw connectors will work,black or blue.
You can even cut the plugs off and put on connectors to use them.
Before you get a pack, test the stator just to be sure.

I always liked aluminum props.The stainless is good but if you hit anything it can really hurt the motor.
Stuff out in the ocean can be just under the surface and it can sink you.
A friend in Md. went out of the Ocean City Inlet. 1/4 mile out he hit a HUGE Loggerhead and was sinking within 5 min.

 

[EricE]

Re: Force 125hp 1986 Odd Noise coming from engine.

Here are some pictures of my boat and of the ignition.





Since I shot the video of my engine idling, I did a little corrosion control on the engine. I used a wire brush to knock off the white powdery corrosion and loose paint then applied a product called Corrosion Block that I got from West Marine. The stuff is expensive but pretty good. It can be used to lubricate just about anything on your boat including electrical connections.

 

[EricE]

Re: Force 125hp 1986 Odd Noise coming from engine.

Jerry, my packs have the individual wire connectors that screw in. I saw a pack for sale on ebay with the connector type plug and notice the wires colors looked the same and was wondering if I could just cut the plug off. Thank you for mentioning that this could be done. Before I buy, I will test the stator.

I bought this whole rig for $1100 and as the seller put it... "Your buying a trailer and I'm throwing in the boat and motor for free". I have put a lot of time doing maintenance on the motor. I have to admit, I think that Force motors get a bad rap. This is a 28 year old motor that has seen good times and bad times where it probably had sat for years. I rebuilt the carbs and fuel pump, put new seals in the lower unit, put in a new starter and solenoid, cleaned up the wiring connectors and did some corrosion control and general lubrication. She fired right up runs good and is pretty easy to work on. Who could ask for anything more?

 

[Mikkohart]

Re: Force 125hp 1986 Odd Noise coming from engine.

force parts

If you want new parts send these guys email.

 

[labawg]

Re: Force 125hp 1986 Odd Noise coming from engine.

Yup, i know Jerry, on mine I cut off the connectors of poor black ones and crimp them on blue ones. I believe the tack is wrong. 6000rpm on a 18 1/2' fiberglass boat but has problems maintaining plane? <I needed to run at 5200 rpm to maintain plane with the 17 and now I can maintain plane at 4200 rpm so now from 4200 to WOT> Seems high to me. While he may have electrical problems something else is probably wrong. Just my opinion ( I'm still a novice with Force Motors)

 

[jerryjerry05]

Re: Force 125hp 1986 Odd Noise coming from engine.

While loking at the pics. I noticed that the temp sensor was taped back.
This is an important thing to have working.
You can find them on e-bay. They are pretty much the same on any Force above 50hp.
While your messing, turn key on and take the lead and touch it to a ground.
It should make the buzzer sound off.

 

[EricE]

Re: Force 125hp 1986 Odd Noise coming from engine.

Anybody know if the power packs from a Force 1990 90hp LDrive will work on a Force 1986 125 hp?
How about a 1989 125 hp force, will it work on a Force 1986 125 hp?

I checked the part numbers at Boats dot net and Crowley marine and they have different part numbers so I am confused as to what I can use.