What Happened?

[And1fixer]

Okay, we were out on the water today. Last week ,we cleaned out the Carbs on our 1983 Suzuki DT140, 4 cylinder. So, we were going pretty good until we notice that the water from the tell-tell hole was going inside the engine cover.The water was almost up to the spark plug boot. So, then the motor started to bogg down and then it shut off. After that, the engine was not able to achieve full speed.We were barley getting on plane.The lower engine cowl was entirely filled up with water. Then we took out the bottom spark plug, and it looked nicked up. What do you think made the engine start to do this?And also, the engine consumes alot of gas, and i mean alot of gas. We are only able to get maybe less than 25 miles out of 12 gallons of gas.Do you think that the carbs out out of wack or what?<br /> Thanks!!

 

[boatster]

Re: What Happened?

Are you sure it was water that was filling the lower cowl? If you were consuming that much gas I think you would see an oil slick behind the motor. Sounds like a carb float is stuck open and gas is leaking out the carb or some fuel line is broken open. Man it could be worse if your spark plug is nicked up. Best I could say is don't take the boat back out until you figure out whats going on. Sounds like you got alot on your plate. Run the boat on your driveway with muffs and try to figure out where all that gas is going. I'm sure it'd be pretty obvious.

 

[bigbrownbuku]

Re: What Happened?

if the plug is nicked up thats not good. do a compression test.

 

[And1fixer]

Re: What Happened?

well, i see a gas slick when i launch the boat, but i don't see a link. do you think it needs the timing done on it? and also, you you think that i need to tear down the engine because when i looked at the spark plug, the electrode was black with some particles on it. Then i put in another spark plug, and it was less extreme, but the electrode was still black. But all of the other cylinders looked fine.This is the bottom of four cylinders.And i ran sea foam through it. Do you think that it is carbon that makes it run like this?

 

[boatster]

Re: What Happened?

Sounds like you might have scored your bottom piston if its got black stuff on it. Is it dry looking or is it wet? If its dry looking and black on the electrodes you've probably run your piston dry without oil and it scored to hell. If its wet and black well then that one I don't know anything about. I scored my pistons recently, the plug electrodes were powdery black and not wet looking. Take off the plugs get a flashlight and look down the plug holes. See if the piston walls are scored. If they are go talk to Rodbolt. And since you say you rebuilt/cleaned the carbs I would suspect you didn't reassemble something correctly. The gas slick is your gas consumption problem most likely <br />You are obviously leaking gas. You should be able to find where thats coming from. Either a leaking fuel line or straight from the carbs, if a float is somehow not closing or is just stuck open.

 

[And1fixer]

Re: What Happened?

Yeah, i think that it was dry. Do you think that i am looking at a rebuild, or will i be able to run it?

 

[And1fixer]

Re: What Happened?

But, it was not powdery black.It was more like burnt on if you know what i mean. The plug had alot of deposits i would say that was on it.

 

[bigbrownbuku]

Re: What Happened?

you need to do a compression test.

 

[boatster]

Re: What Happened?

Yeah or a leakdown test. Get a small flashlight and look down the spark plug hole. Do you see alot of scoring? THis would be heavy looking gouges in the piston wall. I'm no expert but I have firsthand experience with scoring my piston walls on my Suzuki motor. I don't think a compression test will really tell you much but it could be a first start. I'd go straight for a leakdown if you can do it. OH what you could do is remove all the plugs (making sure to keep them in order) and compare how they all look. At the very least you would see which hole was deviating from the rest and what a healthy/normal looking plug should look like. Like I said my scored pistons put an evenly coated powdery black surface on the electrodes and ceramic of my plugs because of the no oil lubricating the hole. Your situation could be totally different from mine. Good luck.<br /><br />Boatster

 

[And1fixer]

Re: What Happened?

Okay, i did not see alot of scouring on the piston , but i did it with the piston at top dead center. I did the timing, and the engine sounds alot stronger, but when i ran it and did a spark plug test, the first one decreased the idle a little bit, the 2nd and 3rd almost shut the engine off, and the bottom one did nothing, but their was alot of spark going to the spark plugs.I think that it could not be seized because it is oil injected and it was smoking all the time when we ran it, and the oil tank decreased in level.

 

[Yepblaze]

Re: What Happened?

Hows those compression readings.<br /><br />A bad powerhead base gasket might let a bunch of water back up under the cowl. Heck, it could water out the plug wire or coil too.<br /><br />If a carb is plugging up on one cylinder and the others take it along for a ride it very well could cause serious piston damage.<br /><br />Again; Check the compression and run motor on the hose and look for water leak under the hood.

 

[And1fixer]

Re: What Happened?

the engine did not leak water anywhere when i ran it. Except that their seems that there is no spark on cylinder 4. The spark boot gives out plenty of spark, but it does not seem to do anything when i take it off.

 

[Yepblaze]

Re: What Happened?

I had one like that once. <br /><br />I took it down the street to that FixAll shop. He said it was the dorsal valve letting the water into the spark gel exciter. Of course I didn't believe him.<br /><br /><br />Again.........<br /><br />How's those compression readings.<br /><br />A bad powerhead base gasket might let a bunch of water back up under the cowl.<br /><br />Run motor on the hose and look for water leak under the hood.<br /><br />How's those compression readings.<br /><br /><br />Does it run better when you squirt gas/oil mix into the carb throat for number four?<br /><br />PS, an additional note.<br />Those old foam lined hoods will allow bits of debris in the carb vents plugging the main jet(s) till removed or corrected.

 

[bigbrownbuku]

Re: What Happened?

i give up.

 

[And1fixer]

Re: What Happened?

I took the boat back to storage, so i cant do a compression test right now, but ill try to do it as soon as possible.

 

[And1fixer]

Re: What Happened?

And, what do you think that good compression readings would look like for the engine?

 

[DJ]

Re: What Happened?

Over 100 psi and within 10 psi of each other.<br /><br />Are we sure the water pressure "tell tale" tube is hooked up? If it has a crack in it, otr is disconnected, it will spray alot of water in the cowl.<br /><br />For whatever reason, the bottom cylinder is dead. No spark, no fuel, or no compression. Now you have to find out which one is missing.<br /><br />By the way, don't EVER expect that engine to be a fuel economy champ.

 

[Yepblaze]

Re: What Happened?

It may not even have a tell tail, as a vintage model I own just comes out with the exhaust bypass or, relief.

 

[boatster]

Re: What Happened?

Lots of willing helpers and good suggestions,<br /><br />going unanswered or just not giving enough info for people to help you out. I give up also....

 

[And1fixer]

Re: What Happened?

no, i just cant get the boat now because i am very busy right now(Christmas shopping). As i have said, the boat has a tell tell hole that water comes out of, that is where the problem originated from. The hose came off and the lower cowl of the engine cover filled up with water, but im trying to get a compression tester today and try to do the test as soon as i can.