Dt 140 no power under load

[chackett]

Might have been my thread you read about the cooling sensor. A point of clarification that many folks don't seem to know. That sensor (at least on mine, and I believe most if not all others) is actually just a flow sensor. In the "closed" position the circuit is "opened" or there should be little to no resistance on your VM. In the open position (the lever pushed to the top), the VM should read "OL" or over limit, of infinite resistance. Basically circuit is closed.

I don't know the exact measurement for the counting coil distance to the actual coils, but it's very close. I know it's close enough that I didn't think it had enough space to account for any variance in the teeth. But it's really close.

Like moonlighter said, check the plugs, the boots and the leads. I'd also check all your ground connections. There are a lot of them, they're easy to miss, and can cause all manner of strange and inexpiable symptoms.

Good Luck,
Chris

[Solarman]

dt140, running issues

AS moonlighter suggested, the tick you hear may be a spark leak, that would go along with the motor stumbling. And if such is the case, running at dark is a good way to find it, just use a non-conductive dry probe if moving any wires, that spark will bite.lol
The #3 carb blowing hoses, jumping as you mentioned, tells me it is misfiring on that cylinder. You may have been right when saying it acted like a cylinder was dropping out, then picking back up, or surging. A spark jumping to ground from the #3 coil wire would be a good probability. look for that first. If you see no spark leak, and have no ”tick” with the Cowling off, then use a long, good plastic handle screw driver, and touch the tip to any ground, then slowly move/ lean the shaft along the plug wire & boot, if leaking it should show up each time that cylinder fires. If still hearing the tick, but no spark leak, let us know. There are other directions to go.
Let us know what you find.

[Solarman]

dt140, running issues

Oh, forgot to mention.
The reed valves are check valves for the positive and negative pressure in the crankcase. If bad you would have crankcase pressure blowing back and forth through that carb where the reeds were bad. And that carb would not pull fuel in.
From what you describe, it appears your #3 carb/ cylinder is misfiring. So let's follow that scenario, and see if we can solve your problem.
Keep us posted.

[Jigging bob]

I dropped oil for winterization it's getting down to 25 to 30 degrees at night up here. I will continue to tinker but won't be able to start it up again unless gets warm again. I may have to wait for spring to get back at this. If it warms up I will drag it back out on lake again.

I really am happy with how helpful you all are. My family Thanks you all so much. I will hopefully win this one.

[Jigging bob]

So counting coil as close to gear as possible? No spec in my manual on distance away from each other.

[Solarman]

dt140,, running issues

Should be a spec for it if you have a good manual? But it has to read each tooth, and don't want it to hit any tooth.
Let us know when you're able to get back at it.

[Jigging bob]

Got back out for spring. The boat landing was in bad shape so could only drop in and run from trailer again. I checked oil filter sensor by unplugging it then ran still had tick and sneeze? We did same with water flow sensor unplugged green wire started and still no change. We also checked water flow sensor with a tester seemed fine there also. (But did not test while motor was running) So those both seem to be ok? Question -Would not purging the system after we did all the work to the oil tank and oil filter cause this tick, hickup then sneeze? Other than this seems to be running good?

Also We tested the plug leads and all were at .07 .08 ohms.

Debating on just buying a New Fuel pump, thermostat, water flow sensor or what this thing has us confused? I am debating on bringing in to have carbs checked again. But I'm Leary on that again because good Suzuki mechanics are hard to come by up here.

[Solarman]

If there is a spark leak, would cause the stumble you're hearing. Is it possible to run at night with Cowling off? Any spark leak is visible at night (when dark), and it does make a tick sound when it jumps to ground. And yes, the whole engine will stutter Fromm that misfire.

Good luck, post us back.

[Jigging bob]

The good news..the gas smell went away. Turns out the underfloor gas tank vent hose going to the chrome vent that goes out the front side of the boat was deteriorated just on the inside of the chrome vent inside boat side by the hose clamp. Loosened clamp slid back cut hose back couple inches reattached to chrome vent and walla no more gas smell. Did same on every other hose connection that was not new hose. Also filled gas tank with no issues spitting gas back at me. So that's a plus.

I will have to try the dark thing for sparks, I have to get some muffs on it.

Thanks again for input.

[Jigging bob]

Can you move the ignition coils around that are connected to Leeds? Each one has a 1 2 3 or a 4 on backs of them. I'm told that's just the firing order and they will work in any spot? Can I put 2 in 3 and 3 in 2 spot as example to see if it runs better?

[Solarman]

I believe the number on the coil is because of the tracer color of the wire that connects to the ecm's matching tracer color, identifying which coil it is. Yes, they can be swapped, as long as the spark plug leads are same length, but don't mix up the firing order.

Post back what you find out.

[Jigging bob]

Had out today on the muffs and garden hose to tinker. I Found out another mistake by dealer I had at.
They had Ignition coil Number 3's grey wire and number 4 coils green wire hooked up to the wrong color wires. they had the grey to green & the green to grey wire. I Put grey to grey and green to green like they are supposed to be, Seemed to help.
I also put a new oil filter sensor on just because I had it.
After tinkering I started to get brave and mess with the carbs a bit. Turned the pilot air screws in all way then backed out 1-1/2 turns and feathered pilot screw on all carbs from there till motor ran better. Got singing pretty darn good. but did notice 4 carb had a flame shooting out for a second until I adjusted pilot then that seemed to stop. Now the number 3 and 4 carbs are spitting gas out. Enough to have gas sitting in bottom of carbs at the open area just in front of the 1st butterfly (on the carbs end that has the pilot screw) some gas will even run out of the carbs after it pools up in there. Does Run much better. What's deal with the gas on 3 & 4 carbs? Do I need to adjust air screws different or another adjustment some where else? FYI - 1& 2 spark plugs looked new, 3 had slight burn and oil, 4 was very black sooty looking all over.
Thanks guys feels like I'm getting closer to getting to take family out.

[Jigging bob]

Oh Ya I did put a towel over the motor in dark garage and did not notice arching on spark plug Leeds?

[Solarman]

Ok, jbob. Just read previous post.
The air mix screws should all be same, the manual tells you to set all at one setting. Check the manual for the setting and set all same. Those mix screws are idle air mix screws, should set them to manual and forget them.

The #3, carbs, gas is in throat (spitting back) of carbs? Both carbs? Then you need to check float settings on both of those carbs. If the float settings are good, you may have a problem with the reed valves on those two cylinders, allowing air flow to blow back, this would cause the fuel spitting back as you mentioned.

The reed valves located under the carb intake manifold operate like check valves for the suction and compression. Fuel, air and oil mixed are sucked into the motor, but as the piston stroke continues there is a slight crossover where it changes from suction to pressure, the reed valves check this so the fuel air mix doesn't blow back.

Still need to know if you hear that click sound, when motor skips?

Need to add. Your motor has 4 ignition timing pulse coils under the flywheel, there is one for each cylinder, if #3, and #4 are miss-firing (wrong time, this could also cause a proverbial back firing through those carbs. This could damage reed valves, if firing improperly.

Post back when able.

[Jigging bob]

I will get the air screws the same.
Yes the throat is where gas is spitting out and sitting. It's not a stream, just mist or light spit. But does build a puddle after a while idling. This is probably why the motor runs better when tilted up and has more issues in full down position. When it's up it is dumping the puddled fuel out. Also bet this is my gas smell I posted in previous posts. Floats may be correct assumption.

Do I need to pull entire carb to check floats or can a guy drop bowl with carb on?

Reeds may be getting over my head, I can surly get to them but putting all back together linked up correctly May be tricky? Boat fires right up like hits right away. Don't reeds make starting harder From what I read on other posts?

I think the click was still there every so often but was more of a miss / pop after I messed around with it. I had people interrupting me the whole time. In city running a boat motor with cover off draws curiosity. Lol