85 HP Force Losing One Cylinder/Bogging After Running Perfect at WOT

[dngbt5]

What I have:
1988 Force 85 hp On a Bayliner Capri 1700 (856X8A)

What I have done:
-Swapped CDI boxes to see if that was causing #1 to fail
-Checked compression 125 on all cylinders when cold
-checked all ground and ignition wires for solid connections
-replaced Trigger
-replaced all fuel lines and bulb
-checked for spark - have good spark on all cylinders
-replaced fuel pump diaphram
-removed and cleaned all carbs
-checked and adjusted timing.

My problem:
-When I first get on the water, my motor starts and idles perfectly. It takes me about 10 minutes of idling to get to the wake zone. When I get there I can hammer down plane out and run @ WOT for about 2-10 minutes depending on the heat and my load in the boat I believe. After letting it sit or idle for a few minutes the motor will take off great at WOT and planes out, but then boggs down after 20 seconds or so. I can then return to 3/4 throttle and it runs fine as long as I do not increase the throttle past 3/4 throttle, If I increase the throttle past ¾, the motor boggs again. If I leave the throttle at WOT too long it completely fouls the Top #1 cylinder and can no longer even run at 3/4 throttle. After checking all three plugs it is only the #1 Plug that is very dark and dirty.
- I have been told that one coil could be heating up and failing. At the end of the year last year I took it out by myself (light load and colder weather) and the motor held up for twice as long as it did with heavier loads and warmer weather.

[NMShooter]

You could check the coil theory by swapping your coils. Exchange #1 and #2 and see if the problem follows the coil.

If not, I think that you can swap the #1 and #2 carbs. While you have the #1 carb off, make sure that the float is not leaking. When you cleaned the carbs, did you check to see if the needles were worn?

[dngbt5]

Thank you NMShooter.... I forgot to mention that at the end of the year last year I did exactly that. I switch coil #1 with #3 and the #3 plug looked to be the problem then and fouling. Today I got a new coil in the mail right after I started this thread. I installed it and hit the water immediately.
Here is what happened. It started perfectly and idled perfectly out to the no wake zone as before. I hit throttle slowly to WOT and it planed out for 3-4 seconds then it began to pulse. I realized I hadn't pumped the bulb on my fuel line so I killed the motor pumped the bulb and took off. I ran at WOT for about twenty minutes. Slowed to an idle for about 5 min and took off again at WOT for another 1-2 mins. After that I figured I stopped and started 5 times like I would if I was pulling a wakeboarder. She did great until the 6th time. At that point she began to pulsate. It seemed like one cylinder wasn't getting enough gas. I left it running and pumped the bulb to no avail so I shut the motor down and opened the cover. I didn't see any problems so I pumped the bulb again while the motor was off. I started her up and she ran perfect for another 5 min. I did the start/stop thing again with the same results. About the 5-6 time she failed again. I shut it of and pumped the bulb then she took off and ran perfect again until I did the start stop thing again. I repeated this one more time with the same results.

Could I be getting air in my fuel line. I found one place right before my fuel pump that looked like it was a little blue/wet with fuel. I do not have a clamp on this line and that is the first thing I am going to do tomorrow. I have checked my tank vent.. It is clear.
When I pump the bulb while the motor is off, I can hear fuel spraying/leaking out and I can see fuel leaking out. Is this just an overflow that should be there or is there a problem somewhere.

[dngbt5]

NMShooter, I forgot to tell you that I did check the needles and I replaced them. Additionally I feel the coil definitely made a big difference. Last year after the motor bogged I would lose the # 3 cyclinder all together unless I cleaned the sparkplug and then it would immediately fail again. At least now all I have to do it shut her down and pumped that bulb, but I feel like I am so close to having her run perfect that I just have to figure this out.

[NMShooter]

I doubt that it is air in the gas line causing the problem. If you had a hole in the line before the pump, you would be sucking air, after the fuel line it has positive pressure from the pump, which goes into the bowl. The bowl fills till the float shuts it off.

Fuel line is cheap though... but it looks as though you replaced all the fuel lines already, right?

Which cylinder did you put the new coil on? How do the plugs look?

I'm a little confused by your need to re-prime. How does the in-tank pickup look? Does it have a filter on the end that has become clogged?

Certainly a weird situation, and sounds like it might be more than one issue here. We need Frank to chime in!

[dngbt5]

The line I noticed is just before the fuel pump and I have replace all lines from the tank to the motor and everywhere on the motor. I must have ran out of clamps and I will clamp that tomorrow. Seems to easy to be the issue.

I never have had the in-tank pickup out to look at it. If it does have a filter that would make a lot of sense. The previous boat owner did say that he would have more troubles with it after it was under half a tank. I can not get the tank out to clean it and I thought about trying to pump it out and clean it with a cleaner, however I read about a guy that did that and it didn't help him out at all. His problem could have been completely different though.

I am definitely going to try and get the pickup out and check it out tomorrow. I have been surprised with how little junk I get in my fuel filter on my motor. Makes me think there is one in my tank.

I am new to this and not sure who Frank is but I hope he does.

Thank you for your knowledge, thoughts and Ideas.

[jerryjerry05]

Not Frank but I'll try.
Any idea how much time on the motor?
What RPM's at wot?The overheat buzzer working?
Try grounding it out.
Clean the carbs,not that hard to do.Make sure the floats are all set the same.
Air screws, front of carb/top.Out 1 full turn and leave it.
Top post or 2 is a post by FrankA called a linc and sinc,do it.
Rebuild the fuel pump.
Remove any inline connectors.Make sure the hoses all have clamps.Zip ties work in a pinch.
What plugs are you runing?
Aftr this the fuel recirulation system might need cleaning.

[NMShooter]

Can you borrow a portable tank for that motor?

Still has me confused that only one cylinder was getting fouled, and it followed the coil, then you replaced the coil and the problem still occurs (although it sounds as though it might be a little better).

[dngbt5]

Yes I do have a portable tank and that is a great idea. That will help me eliminate the in tank filter theory. Additionally I forgot to put on this post that after squeezing the bulb and filling the carbs, I can hear fuel spraying out of the overflow. I wasnt sure if this was normal, but I have been told on another thread that it is not. Since I know for a fact that this is def. an issue I am going to tackle that first. I cam going to remove the carbs again, clean them, check the seats on all my needles and clamp that fuel line. I will hopefully be ready for another test run by Friday.

Thanks again for your help.

[dngbt5]

I ran the boat today and it may have been the most rewarding trip I have ever taken. I believe that much of the work I did before this was definitely not a waste of time or money. I know there were multiple electrical issues I fixed but If I learned anything from this, it would be to: 1. get on this website and create your own thread explaining your situation, 2. take your time and double check your work before moving to the next possible problem. I spent a long time reading old threads relating to my issues and working off of them but it only took me a few days to eliminate the most recent problem I had after starting this post. Thank you all for your help and especially jerryjerry05 for explaining the carb/needle issue. Gotta throw a shout out to NMShooter also for all the help and info. I pray this is the last time I have to get on here to find a solution to my problem, but I promise to do my best to keep checking threads and helping anyone else I can

[dngbt5]

Ok I took the boat back out today and was very happy for a couple trips around the lake. After starting and stopping a three times I took off again, the boat planed out I slowed to a crawl for an on coming fisherman and took off again. She once again planed out again but after a few moments the motor began to pulsate and lose power. I stopped, removed the spark plugs and the third cylinder looked dry compared to the other two. I took off again a couple times with the same results. It definitely seems to be a carb/fuel issue.

What could be causing this problem?

Seems that this float/needle is sticking to me?

I have replaced the fuel pump diaphram. Is there anything else I could do with the Fuel pump? Needles to clean/replace?

[dngbt5]

I removed the carbs, cleaned them, and check to make sure all needles and floats were working correctly. Everything looked good. I also checked out the linc and sync thread from Frank A and followed his instructions to the T. Also I adjusted the timing and have it set to the single mark at idle. There is a triple III mark also but it didn't seem that I could even adjust it to that point. Is the single I mark correct at idle? I took the boat again yesterday after working on it again and it ran great. However, I was by myself and there was no load on the boat. Today I took it out again and had three friends in the boat and it ran good also, It was a little slow on the whole shot but I probably had about 800 pounds in the boat at the time. I was really proud of the boat and then another buddy showed up and he weighs about 230 himself. After he got in the boat I took of and it took a little bit but the boat planed out, but soon after maybe 20 seconds the boat once again began to bog and lose power. If I stopped for a few seconds and took another whole shot it would once again plane out and then bog. Seemed to be losing one cylinder. I checked all the plugs and they all looked the same (pretty dark wet and dirty, but they always have been) none were dry as the number three had been previously. I am thinking I am running the carbs a bit rich, and under the heavy load I am fouling a plug. I have the turned the jets to about 1 to 1&1/4. I am a little worried that the guy who worked on this boat before I owned it over tightened the screws and may have damaged the seats as they were all the way closed when I got the boat and it still ran. I am scared to closed them any further as Frank A says not to close past 3/4 and most people have said 1 to 1&1/4 works good.

I have replaced the screws themselves and they seem to be a little loose ( they turn very easily and am worried they may vibrate open or closed) Could this be my problem. It sure seems to be a fuel issue to me.

[riptorn]

I have the same motor. I bought it last summer. So I don't know too much about it right now. How does it start when it is cold? There is another post here where someone said to replace with an outboard gas tank to see if it was the problem. I don't think you replied on that.

[dngbt5]

Had the boat out a couple times since I was last on here. I took it out the first time and it ran horrible. After messing with the air screws on the carbs I realized that I could close them completely and the motor still ran. From what I know this should not happen. I am guessing that the guy who worked on it before I bought it drilled the seats out because he couldnt get it running or was trying to get more horsepower?. So what I did was close the top two carb screws and open the bottom one about 1 1/2 turns out.
It ran awesome immediately after that for about six trips around the lake until I went in. I checked the plugs and the top two look nice and wet with fuel and the bottom one was too but not as fuel soaked as the top two. I took it back out on Sunday and it ran awesome again I even went wake boarding for a while and then all the sudden she lost power again.
I did notice that the bulb was all the sudden ca lapsing, when I would squeeze it it did run better. I was about at half a tank at that point. I did check the fuel pump diaphram and the filter before it and it looked good.
I know I have a problem with the seats, but she seems to be starving for fuel. I have been told there is not a filter in the tank, but I am wondering about it now?
Do I need to buy new carbs? I dont think there is anyway to fix the seats? Are there screws that I could find to actually make a good Seat and therefore be able to adjust them?

Please Help

[dngbt5]

When I get the boat back out I am going to connect it to another tank to eliminate that issue. I may end up buying a set of used carbs if that doesnt work

[bentle]

Most large tanks have a pre screen on the bottom of the fuel pickup tube. Also is your fuel tank vent working properly. Is it plugged? Or is the vent line full of fuel?

[florida blue water]

sounds correct. well said

You could check the coil theory by swapping your coils. Exchange #1 and #2 and see if the problem follows the coil.

If not, I think that you can swap the #1 and #2 carbs. While you have the #1 carb off, make sure that the float is not leaking. When you cleaned the carbs, did you check to see if the needles were worn?

[dngbt5]

Ok I solved the collapsing bulb issue. I found that there was a bad connection coming on the bulb itself.

I took the carbs off again and wanted to check and see if anything else looked worn. I found that the Idle mixture screws were worn near the tip. I am ordering them tomorrow the originals were set to 1 1/2 turns out. Is that correct?

I also noticed that the top two float needles (neoprene tips) looked slightly worn. I thought I had replaced all three but they are different from the one that I know I replaced. They are red neoprene and my replacement has black neoprene. I am also ordering new seats for this valve. I believe I can just remove them with a hook tool and press new ones in?

Could these bad parts be causing my problem. The boat will now take off great get to plane and then pulsate/lose and regain power. Seems to be running out of fuel or fouling. After looking at the plugs they seemed to be cold fouled.

[bentle]

Something you may want to check is all of the small wires on the power strip right at the butt connectors
the small wires can break and short out right under the heat shrink.