85 force lower unit drain plug

topgun3690

Lieutenant Junior Grade
Joined
May 7, 2019
Messages
1,031
the guy i bought it from said he had just done the CARB before i bought it... hopefully his word was honest.
Take nothing for granted when acquiring a new to you engine. He may be honest and "done" the carb (there are 3) but no telling if he did a good job or knew what he was doing. (y)
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
37,562
I can not touch , see or hear your motor.-----You have to do the work or learn how to do it.----Might not be easy or affordable to get a shop to work on it.
 

sidewing

Seaman Apprentice
Joined
Aug 9, 2024
Messages
46
I checked the RPM at idle and it seems to be around 800. I'll take it on the lake at some point this week close to the house and try to get some different readings at WOT and actually in the lake vs a tote bucket.
We're pretty close to sea level here, and we took the boat up to shaver lake, which is 5500 feet elevation yesterday.. I filled the gas tank up before we left (probably shouldn't have, should've left it at half a tank).. and the engine seemed to be running quiet at idle.. rpms seemed much lower to the ear.. and it would choke out slowly and die eventually at idle and even at the first click forward (which is usually where I cruise to troll, which is about 3mph).. and if I tried to go full throttle, it would also choke out slowly and die.. if I kept it at a sweet spot at maybe 2/3 throttle, it would run fine without dying. I could throttle it back n forth and eventually get it to take full throttle, then it would continue running at full throttle without issue...
Looking for some thoughts on this.. is this to be expected because I was at 5500 ft elevation and less air available? (Vs the maybe 50 to 100 feet elevation I live at)..
I have it on my list next to do a carb cleaning, and also to do Frank's video on the carb and timing.. it seems like a lot and hopefully I don't screw it up.. but at this point I don't really have a choice, since it's me or nothing around here where I live.
 

sidewing

Seaman Apprentice
Joined
Aug 9, 2024
Messages
46
Forgot to mention, there is a little fram looking fuel filter in line right before it goes into the engine. I haven't changed it yet though
 

Jiggz

Captain
Joined
Oct 23, 2009
Messages
3,903
Forgot to mention, there is a little fram looking fuel filter in line right before it goes into the engine. I haven't changed it yet though
Need to specify this location. Normally, for troubleshooting purposes the fram fuel filter (see thru) should be after the fuel pump and before the carbs. Also, there is a built in fuel filter on top of the fuel pump and can be easily removed with a flat tip screw driver. This is nothing but a very fine mesh of stainless steel mat. Ensure this is clean also.

For fuel troubleshooting, a quick glance of the see thru fuel filter will tell you if the fuel pump is delivering optimal fuel to the carbs. It should at least maintain fuel level no less than half of the filter when at WOT.

As for the high altitude operation, the rule of thumb is that for every 1000 feet of elevation, you lose 3 percent in power output. At 5,500 ft, that corresponds to 16.5 percent lost of output power. And if no re-jetting is made and continue to operate at high altitude there's a good chance the spark plugs will get fouled. Note re-jetting for high altitude ops doesn't restore lost output power but only avoids fouling due to rich fuel-air ratio.

Idle rpm at 800 in neutral is low. Usually, this is around 1000 rpm. Now idle rpm in gear in water at 800 is about right although recommended is 700~750 rpm. The idle rpm adjustment is at the bottom of the timing tower if you need to make adjustment. You'll need an open 7/16 wrench and a flat tip screw driver. CW to increase and CCW to decrease.
 

sidewing

Seaman Apprentice
Joined
Aug 9, 2024
Messages
46
Need to specify this location. Normally, for troubleshooting purposes the fram fuel filter (see thru) should be after the fuel pump and before the carbs. Also, there is a built in fuel filter on top of the fuel pump and can be easily removed with a flat tip screw driver. This is nothing but a very fine mesh of stainless steel mat. Ensure this is clean also.

For fuel troubleshooting, a quick glance of the see thru fuel filter will tell you if the fuel pump is delivering optimal fuel to the carbs. It should at least maintain fuel level no less than half of the filter when at WOT.

As for the high altitude operation, the rule of thumb is that for every 1000 feet of elevation, you lose 3 percent in power output. At 5,500 ft, that corresponds to 16.5 percent lost of output power. And if no re-jetting is made and continue to operate at high altitude there's a good chance the spark plugs will get fouled. Note re-jetting for high altitude ops doesn't restore lost output power but only avoids fouling due to rich fuel-air ratio.

Idle rpm at 800 in neutral is low. Usually, this is around 1000 rpm. Now idle rpm in gear in water at 800 is about right although recommended is 700~750 rpm. The idle rpm adjustment is at the bottom of the timing tower if you need to make adjustment. You'll need an open 7/16 wrench and a flat tip screw driver. CW to increase and CCW to decrease.
Here's the filter. I'll check the mesh filter under the flat head.

 

topgun3690

Lieutenant Junior Grade
Joined
May 7, 2019
Messages
1,031
That pic shows the filter on the inlet hose to the pump......which won't hurt anything, but you really want it on the pump outlet hose that goes to the carbs.....that way you can tell if the pump is working or not. May have to reroute that outlet hose.....they got it kinda crammed in there behind other stuff.
 
Last edited:

sidewing

Seaman Apprentice
Joined
Aug 9, 2024
Messages
46
The mesh filter looked ok. I do see a little speck of something floating around inside of the clear filter when I pump the ball pump to prime it. I'll replace that filter.
I ordered some spark plug testers so I can verify if I have spark on all 3. I jumped the gun and didn't research this first and removed the boot 1 at a time to see if I could see spark when I put the boot close to the plug.. I thought that I had seen that on a video, but now I have to bow my head in shame and own up to it... Couldn't see anything on any of them.. I was using an insulated spark plug remover with a glove on, but my finger grazed the metal on number 2 and I felt a little electrical jolt slightly. When I removed the 3rd one, the engine died. (I was doing them 1 at a time).. engine wouldn't restart.. I let it sit for about 15 minutes and it started, with a single "pop" backfire when it did. Shut it off and started it again with no pop. Now, I see I shouldn't have done that because the plugs need to be grounded and I could've fried the CDI units, which I see there are 2 of them (one for 1 and 2 and one for 3)... I think they're probably ok since it started up after the fact (I hope)..
The in line spark testers should be here tomorrow, so we'll see if I'm getting spark on all 3.. (if not, that would be likely why the engine is running slow at about 8mph as was mentioned to me in an earlier post).
I see a random connector plug just sitting there behind the coils, but it looks like all 3 coils are connected, so maybe that second CDI that powers the number 3 coil has an extra open 4th connector?
 

Jiggz

Captain
Joined
Oct 23, 2009
Messages
3,903
The mesh filter looked ok. I do see a little speck of something floating around inside of the clear filter when I pump the ball pump to prime it. I'll replace that filter.
I ordered some spark plug testers so I can verify if I have spark on all 3. I jumped the gun and didn't research this first and removed the boot 1 at a time to see if I could see spark when I put the boot close to the plug.. I thought that I had seen that on a video, but now I have to bow my head in shame and own up to it... Couldn't see anything on any of them.. I was using an insulated spark plug remover with a glove on, but my finger grazed the metal on number 2 and I felt a little electrical jolt slightly. When I removed the 3rd one, the engine died. (I was doing them 1 at a time).. engine wouldn't restart.. I let it sit for about 15 minutes and it started, with a single "pop" backfire when it did. Shut it off and started it again with no pop. Now, I see I shouldn't have done that because the plugs need to be grounded and I could've fried the CDI units, which I see there are 2 of them (one for 1 and 2 and one for 3)... I think they're probably ok since it started up after the fact (I hope)..
The in line spark testers should be here tomorrow, so we'll see if I'm getting spark on all 3.. (if not, that would be likely why the engine is running slow at about 8mph as was mentioned to me in an earlier post).
I see a random connector plug just sitting there behind the coils, but it looks like all 3 coils are connected, so maybe that second CDI that powers the number 3 coil has an extra open 4th connector?
With nr 3 wire plug disconnected and engine shutting down, tells me there is a misfire and obviously it is not on nr. 3. The reason it shuts down when you took off wire plug 3 because that particular cylinder is actually working. So you can still do the same with nr 1 and 2 but have to do it quickly while listening for change in rpm. If there's no change in engine rpm or tone when you pull a plug wire that is an indication that cylinder is not firing. Either due to fuel-air mixture problem, lack of compression or lack of spark.
 

sidewing

Seaman Apprentice
Joined
Aug 9, 2024
Messages
46
With nr 3 wire plug disconnected and engine shutting down, tells me there is a misfire and obviously it is not on nr. 3. The reason it shuts down when you took off wire plug 3 because that particular cylinder is actually working. So you can still do the same with nr 1 and 2 but have to do it quickly while listening for change in rpm. If there's no change in engine rpm or tone when you pull a plug wire that is an indication that cylinder is not firing. Either due to fuel-air mixture problem, lack of compression or lack of spark.
I didn't notice any change when I pulled 1 or 2 (other than the tiny little electrical jolts I felt when I pulled 2). I guess that means there's a SOME electrical going to 2.. compression was good on all 3. Assuming they pass the spark test tomorrow, it's looking like something with air/fuel.
Is it possible to be running off 1 cylinder this whole time?
I'm gonna do the carb and idle adjustment tomorrow as well and see where I'm at.

I've noticed the whole time I've had the boat, when I'm in idle, it will sound like it's missing something at random.. like a pause or hesitation.. every once in a while it'll kill the engine, but I've always been able to restart it. I assume that's the misfire.
 

Jiggz

Captain
Joined
Oct 23, 2009
Messages
3,903
I didn't notice any change when I pulled 1 or 2 (other than the tiny little electrical jolts I felt when I pulled 2). I guess that means there's a SOME electrical going to 2.. compression was good on all 3. Assuming they pass the spark test tomorrow, it's looking like something with air/fuel.
Is it possible to be running off 1 cylinder this whole time?
I'm gonna do the carb and idle adjustment tomorrow as well and see where I'm at.

I've noticed the whole time I've had the boat, when I'm in idle, it will sound like it's missing something at random.. like a pause or hesitation.. every once in a while it'll kill the engine, but I've always been able to restart it. I assume that's the misfire.
No it's not possible for a 3 cylinder motor to run on just one cylinder, even at no load. If the motor is firing on all cylinders, pulling one plug wire will definitely give you a change in rpm corresponding with change in engine noise or tone. Again, you will need to familiarize yourself on how it sounds or even better with a tach to see the change in rpm. Make sure you pull the plug wire far enough that it doesn't allow arc jump to the spark plug itself. A good two or three inches from the top of the spark plug at least.

If you are worried about the CD modules, you can install a temporary ground wire that is within reach of the plug wires. So when you unplug a wire put it on top of this ground wire to discharge it to ground. Although, I've never done this and usually just pull the plug wire for about 5-7 secs to have a good listen to change in rpm.

As for the carbs, unscrew the fuel air mixture screw all the way out and inspect the tip. If should be smooth and pointed. Thread it back in until it bottoms but only lightly. Then screw it out 1 1/4 turn out. Do all three and see how it runs. This is the factory setting for this idle mixture screw. From here you can make very little adjustment, i.e. only a 1/4 turn in or another 1/4 out, i.e. 1 turn out or 1 1/2 turn out from lightly seated. But usually, at 1 1/4 the carb should be set for idle mixture correctly.
 

sidewing

Seaman Apprentice
Joined
Aug 9, 2024
Messages
46
Alright so I connected the spark plug tester to each one.. number 1 has little to no spark.. it makes the tester light shine just a little bit but basically nothing. Number 1 also has a tear hole in the back of the boot.. almost like someone rammed the spark plug through it at one point. Lit the tester maybe 10 percent brightness at best.

Number 2, the spark is better, but still not full strength.. I'd say it lit the tester light to about 50 percent brightness.. didn't see any irregularities in the flash pattern.. there is also a very small little hole in the cable boot..

Number 3 was full strength brightness on the tester light.. also no irregularities in the strobing pattern, which would indicate a misfire if there was.

So it looks like at a minimum I should be replacing the spark plug cables on 1 and 2.. but it seems like the other end is fully inside the ignition coil pack... Is it possible to replace just the cable, or do I have to replace the whole coil? Is it possible to just wrap the cable with electrical tape to try to seal the little rip in the cable? The metal connector inside seems loose (the part that snaps onto the plug)..

I want to get this squared away.. and I was thinking of proactively replacing the fuel pump diaphragm.. before I move onto the carb and idle tuning.. that way I don't have to do it again if there's other issues with the ignition cables and fuel flow.
 

sidewing

Seaman Apprentice
Joined
Aug 9, 2024
Messages
46
Ordered a spark plug crimper and boots. Gonna see if I can repair the crimp connectors/boot damage and restore the strong electrical flow, hopefully.
 

Jiggz

Captain
Joined
Oct 23, 2009
Messages
3,903
Ordered a spark plug crimper and boots. Gonna see if I can repair the crimp connectors/boot damage and restore the strong electrical flow, hopefully.
Basically, you can only replace the plug wire boot but not the entire plug wire as it is permanently connected to the coil packs. When replacing the boot, make sure you do not cut off the wire too short. Instead, open the old boot with a sharp knife, de-crimp the existing connector terminal and hopefully have enough wire length left to crimp a new terminal and boot. Hopefully, this will fix the low spark. Or else, you might have to buy new coils or maybe a CD module.

The 85 HP has two CD modules, with one module (feeding #3 cylinder) having a spare ckt. If after replacing the plug wire boots and the problem persists, you can try switching one coil pack (either 1 or 2) to number 3 coil pack and see if the low spark follows, i.e., after switching and #3 has the low spark and #2 has good spark. If this is the case then the problem of the low sparks is in the coils. NOTE SWITCHING COILS INVOLVES PHYSICALLY DISCONNECTING THE CD MODULES FROM THE COIL END AND PHYSICALLY MOVING THE COIL AND NOT JUST SWITCHING PLUG WIRES FROM ONE CYLINDER TO ANOTHER.

Notice, #1 and #2 coils are fed from the same CD Modules. The fact that both have low sparks is an indication that it could be the CD module that is the problem. But only a diagnostic test will do unless you have a spare CD module you can use for testing.

However, if the problem did not follow, i.e., low sparks stays on #2 and #3 continues to have good sparks, then the next step is to switch the modules. NOTE SWITCHING MODULES OR COILS MEANS ALL CONNECTIONS (FROM TRIGGER AND STATOR) SHOULD STAY IN EACH DESIGNATED CYLINDERS EXCEPT FOR THE PLUG WIRES FROM THE COILS WHICH FOLLOWS WITH THE COILS SINCE IT'S PERMANENTLY CONNECTED.
 

sidewing

Seaman Apprentice
Joined
Aug 9, 2024
Messages
46
I'm still waiting for the boot and crimp delivery.. Amazon is usually here a few hours earlier.. but I went ahead and did what I could while I'm waiting:
I followed Frank's video and guide so I reset the carbs, set the cam to the roller, set the ball link, made sure the carbs are straight out at WOT.. I started it up and I'm getting 1020 rpm on wire 3 (my known good wire).. which is in a plastic tote that is not ideally deep enough and I can't put it into gear...

I can't seem to find anywhere where the air fuel mixture screws are so I can reset them back to 1.25 turns.. I see a lot of mention about them, but nothing referenced in video or pictures. Where are they exactly?
 
Last edited:

sidewing

Seaman Apprentice
Joined
Aug 9, 2024
Messages
46
I connected the testers again and made sure they were in as good as possible.. I'm getting spark on 2 and 3 tonight... Nothing on number 1.. I cut the boot off with a razor, crimped on a new connector, slid a new boot.. and it backfired once when I started it the first time, but still no spark on number 1.. it's feeling like I need a new number 1 coil. I may swap em around tomorrow to see if it follows the coil, or I might just order one and hope it fixes it.
Any thoughts on if the coil is the likely culprit? Here's a video of the cable boot/crimp replacement and testing:

 

Jiggz

Captain
Joined
Oct 23, 2009
Messages
3,903
I'm still waiting for the boot and crimp delivery.. Amazon is usually here a few hours earlier.. but I went ahead and did what I could while I'm waiting:
I followed Frank's video and guide so I reset the carbs, set the cam to the roller, set the ball link, made sure the carbs are straight out at WOT.. I started it up and I'm getting 1020 rpm on wire 3 (my known good wire).. which is in a plastic tote that is not ideally deep enough and I can't put it into gear...

I can't seem to find anywhere where the air fuel mixture screws are so I can reset them back to 1.25 turns.. I see a lot of mention about them, but nothing referenced in video or pictures. Where are they exactly?
The initial setting of 1 1/4 turn out is more like a good engineering practice when recommending settings on the fuel air mixture. Technically, the initial setting (take note initial setting is not the same as recommended setting) per manufacturer's document is 1 turn out from lightly seated. However, on the same document it also tells you not to set it below 1 turn out from lightly seated. As a personal precautionary step, I always recommend 1 1/4 turn out (as initial setting) instead of 1 turn out to give some leeways of adjusting it to either CW or CCW to 1 - 1 1/2 turn out. Others had better idling as 1 turn out but that is the minimum setting. While other had it better at 1 1/8 turn out and a few as high as 1 3/4 out.

The video is very telling and yes no spark on #1. Switch coils and that should give you a very good diagnostic indication if it's a coil or CD module or trigger wire problem. Obviously, if the problem follows then the coil is bad. But if not, then need to test the CD module. Also double check the continuity of the wire from the CD module to the coil. And then the trigger wire from the CD module to the trigger.

If you have a DVA adapter for a VOM or digital multimeter with a DVA reading, you can just read the output wire from the CD module feeding to #1 coil and you should at least read 180+ volts at cranking speed. This is an indication the CD module is working properly. With this info, you can hypothesized that the coil is bad. But by switching you can definitely pinpoint if it's the coil or not.

If you're not reading output voltage from the CD module, with the DVA adapter, read the trigger wire and you should at least have 0.5+V at cranking rpm. At normal engine idling, I usually read more than 1.0 volt from the trigger wire.

If you have not used DVA adapters before, there's a plethora of u-tube video that'll show you.
 

sidewing

Seaman Apprentice
Joined
Aug 9, 2024
Messages
46
The initial setting of 1 1/4 turn out is more like a good engineering practice when recommending settings on the fuel air mixture. Technically, the initial setting (take note initial setting is not the same as recommended setting) per manufacturer's document is 1 turn out from lightly seated. However, on the same document it also tells you not to set it below 1 turn out from lightly seated. As a personal precautionary step, I always recommend 1 1/4 turn out (as initial setting) instead of 1 turn out to give some leeways of adjusting it to either CW or CCW to 1 - 1 1/2 turn out. Others had better idling as 1 turn out but that is the minimum setting. While other had it better at 1 1/8 turn out and a few as high as 1 3/4 out.

The video is very telling and yes no spark on #1. Switch coils and that should give you a very good diagnostic indication if it's a coil or CD module or trigger wire problem. Obviously, if the problem follows then the coil is bad. But if not, then need to test the CD module. Also double check the continuity of the wire from the CD module to the coil. And then the trigger wire from the CD module to the trigger.

If you have a DVA adapter for a VOM or digital multimeter with a DVA reading, you can just read the output wire from the CD module feeding to #1 coil and you should at least read 180+ volts. This is an indication the CD module is working properly.

If you're not reading output voltage from the CD module, with the DVA adapter, read the trigger wire and you should at least have 0.5+V at cranking rpm. At normal engine idling, I usually read more than 1.0 volt from the trigger wire.

If you have not used DVA adapters before, there's a plethora of u-tube video that'll show you.
Thank you for all the info and help so far.. where are the adjustment screws though? Just so I know.

I ordered a coil from eBay. 75 bucks in total. Should be here in a few days.. I'm gonna replace coil 2 with the one coming in from eBay.. and I'm gonna move that known good coil 2 to the coil 1 spot and see.. im thinking either number 1 will continue to be bad with a known good coil, then I'll continue further up Creek (and I'll save my old removed coil as probably good Incase I ever need it, cause there isn't many available online)... Or alternatively, all should hopefully be good and firing on all 3.
 

Jiggz

Captain
Joined
Oct 23, 2009
Messages
3,903
The fuel air mixture screw is easily identifiable with a spring in its body. Usually, it sits on top of each carb or sometimes right there on the very front of the carb. When situated on the front, it's not easily visible as it is recessed. To see it, you will need to remove the air covers for each carb and on the very top of the face of the carb there should a a recessed screw (#23).Carb 85 HP
 

sidewing

Seaman Apprentice
Joined
Aug 9, 2024
Messages
46
The fuel air mixture screw is easily identifiable with a spring in its body. Usually, it sits on top of each carb or sometimes right there on the very front of the carb. When situated on the front, it's not easily visible as it is recessed. To see it, you will need to remove the air covers for each carb and on the very top of the face of the carb there should a a recessed screw (#23).Carb 85 HP
Thanks for that picture.. I still had trouble and was looking all over with the camera.. only to find it was staring me right in my face LOL.. embarrassed.. it is right smack in the top center of each carb, but was recessed like you said.. I put them all at 1.25 turns back from lightly seated.. once I get all 3 coils firing, I'll take it to the lake and fine tune these as well as the idle screw.. (800rpm idle and 700 in gear).. I took it to the lake 2 days ago just for a hour so the dogs could test their new life vests with my wife... And I noticed the engine ran really good.. but when it was warmed, I had trouble starting it.. I had to put it in neutral high for it to start.. seems like maybe the idle screw is a tad too low probably? (I forgot to bring my tach that day).

IM GETTING CLOSE!

I also am going to move my fuel filter to the back side of the fuel pump, right before it goes into the carb.. and I ordered a new fuel diaphragm just to be thorough.. maybe I'll just look to get a fuel water separator in place of the current fuel filter to place before the fuel pump. If I do this, is it redundant/not necessary to have a cheap wix filter after the pump, before the carb? Wondering if it'll affect fuel flow too much.
 
Top