Starts on land but not in water

[ctparks]

Re: Starts on land but not in water

Are you sure there is no spark, or are you just guessing?.

No, I know I have spark when on the land cause it will fire up and run with no problems. It's when I put it in the water that it won't start. I have not checked for spark while in the water, but I thought it was safe to assume that if it was starting and running on land that I should have spark in the water as well. Is there something in the system that would prevent it from having spark only when its in the water?? When I lower it into the water while it was already running it would continue to run, but when I went from fwd or rev and back to neutral it usually would die especially if i moved it slow. I'm really just can't see how ignition could be the problem in this situation.

 

[ziggy]

Re: Starts on land but not in water

but when I went from fwd or rev and back to neutral it usually would die especially if i moved it slow. I'm really just can't see how ignition could be the problem in this situation.

back to the lower shift cable.

so when was it replaced last?
if the cable drags, it will actuate the shift interrupt switch. that kills ign.
the cable that actuates the shift interrupt switch only works in the water...

i believe it's already been suggested, but check for spark in the water... after the failure.

 

[ctparks]

Re: Starts on land but not in water

back to the lower shift cable.

so when was it replaced last?
if the cable drags, it will actuate the shift interrupt switch. that kills ign.
the cable that actuates the shift interrupt switch only works in the water...

i believe it's already been suggested, but check for spark in the water... after the failure.

I'm not sure when it was replaced last, but I had read the sticky on this problem and checked for it on the water to the best of my limited knowledge. When I move the throttle on the water fwd or rev it engages the sw and when I go back to neutral the sw opens immediately...there is no sticking of the sw or the cable that I can see. Is there something I'm missing that I should be looking at? Also, you can check our post #20, I also removed the sw from being actuated at all so that it was open all the time to see if that changed anything, but didn't. Thanks

 

[180shabah]

Re: Starts on land but not in water

The switch should not engage when going into gear, only when you are going OUT of gear into neutral.

 

[haulnazz15]

Re: Starts on land but not in water

He bypassed the shift-interrupt switch to verify it wasn't the problem, guys. Move on to other causes.

 

[ctparks]

Re: Starts on land but not in water

The switch should not engage when going into gear, only when you are going OUT of gear into neutral.

When I put mine in gear, there is a plate that rotates and engages the tab on the switch. So, when it's in gear the button on the sw is pressed and when its brought back to neutral the button is depressed. Maybe, I was wrong in my thinking that when the button is pressed on the sw it is engaged.

 

[CharlieB]

Re: Starts on land but not in water

The shift interrupter switch activates BOTH going in AND out of gear. This is NOT his problem.

The possible difference in and out of the water, besides exhaust back pressure from submerging the outdrive causing more exhaust back pressure, is as Don pointed out, the difference in attitude or angle of the craft, a possibility of maybe a bead of water in the carb float bowl, blocking a fuel jet.

Basic troubleshooting, checking for spark, should solve whether it is an ignition or fuel problem.

Fuel has my vote.

 

[ctparks]

Re: Starts on land but not in water

The shift interrupter switch activates BOTH going in AND out of gear. This is NOT his problem.

The possible difference in and out of the water, besides exhaust back pressure from submerging the outdrive causing more exhaust back pressure, is as Don pointed out, the difference in attitude or angle of the craft, a possibility of maybe a bead of water in the carb float bowl, blocking a fuel jet.

Basic troubleshooting, checking for spark, should solve whether it is an ignition or fuel problem.

Fuel has my vote.

I'm going to tear into the exhaust a little tonight to first see if my flappers has went downstream and blocked up my exhaust creating more backpressure than the motor can overcome in the water. Then hopefully i can get her down to the water this weekend to see if the problem still exists and if there's spark while in the water.

As I've said before this problem only started after I overheated it and changed the raw water pump, t-stat & exhaust hoses. I have not messed with the carb tuning or shift linkages since my first time out this year when she started fine on & off the water. I'm still thinking its a back pressure problem, but of course I won't know until i can get in there and look. Thanks for all your inputs...this site always teaches me alot as i go.

 

[CharlieB]

Re: Starts on land but not in water

If one or both shutters overheated and came off then the pieces would be at the 'Y' pipe, not readily accessible from the engine side, not impossible, but you will be working by braille.

Pull the outdrive and look in thru the exhaust bellows with a small flashlight.

The last time I had to break the shutters into smaller pieces to fish them out the drive side rather than pull the motor and the 'Y' pipe. Really a p.i.t.a.

 

[ctparks]

Re: Starts on land but not in water

If one or both shutters overheated and came off then the pieces would be at the 'Y' pipe, not readily accessible from the engine side, not impossible, but you will be working by braille.

Pull the outdrive and look in thru the exhaust bellows with a small flashlight.

The last time I had to break the shutters into smaller pieces to fish them out the drive side rather than pull the motor and the 'Y' pipe. Really a p.i.t.a.

Last night I took the exhaust apart from the manifold down to the Y-pipe and the flappers on both sides are gone. I ran flexible fingers down the Y-pipe till I could see it through the exhaust outlet at the back of the boat and did not encounter any resistence or see any pieces of the old flappers. I then went through the back and up the Y-pipe with the same results. I looked through the stern drive as well and did not see them anywhere. I'm not sure if the flappers disentegrated and blew out or if they where never there to begin with. If there are no flappers installed at all would it cause this problem as well?

Well, there is one dead raw water pump. I also suppose you had the outdrive in the full up position while it was running????.

Also, Don you where right...I thought I had the stern drive in the water everytime I tried cranking her with the exhaust out of the water, but evidently I was WRONG! When I started her up last night on muffs, there was hardly any water circulating up to the motor and out the exhaust now. So I will be changing the water pump impellar again today. Since I just changed the whole thing, could I get by with just changing out the impellar or do I need to change out the water pump housing and everything too?

 

[Don S]

Re: Starts on land but not in water

Since I just changed the whole thing, could I get by with just changing out the impellar or do I need to change out the water pump housing and everything too?

That all depends. That pump has a plastic housing, and it's probably melted, may even have damage to the lower housing, they are plastic too.
Only way to know for sure is to take it apart and look at it.

 

[ctparks]

Re: Starts on land but not in water

That all depends. That pump has a plastic housing, and it's probably melted, may even have damage to the lower housing, they are plastic too.
Only way to know for sure is to take it apart and look at it.

Yea, I just talked to the marine center and they basically told me the same thing. He said it takes about 12 seconds to ruin the impellar and then they start heating up and melting things. I'm going to get the kit and change it out again.

As far as the exhaust flappers in my previous post...if there are no flappers in there at all...would it cause it not to start in the water and what kind of problems am I looking at having without them?

 

[Don S]

Re: Starts on land but not in water

The flappers are not your problem. There are exhaust relief passages that will allow the engine to start, even if the old flappers blocked the outdrive.

When you try to start the engine in the water, do you give it any throttle? Or are you trying to start it like a car with EFI, just turn the key and it runs?

 

[ctparks]

Re: Starts on land but not in water

When you try to start the engine in the water, do you give it any throttle? Or are you trying to start it like a car with EFI, just turn the key and it runs?

No, I can't give it any throttle when cranking...there is a kill sw somewhere that as soon as I move the throttle while cranking it kills ignition. Usually, it will start and I will move the throttle lever on the carb just enough to get up to idle and stable.

 

[Don S]

Re: Starts on land but not in water

I think we found your problem.
On your shifter there is a button you either push or pull for neutral only.
So you can use just the throttle.
Can you post a picture of your control.

 

[ctparks]

Re: Starts on land but not in water

I think we found your problem.
On your shifter there is a button you either push or pull for neutral only.
So you can use just the throttle.
Can you post a picture of your control.

I think I found what you're talking about now....wow do i feel stupid!! So, I'm taking it that when I push the black button on the side there, I should be able to move the throttle while cranking??

 

[Don S]

Re: Starts on land but not in water

That's an old Morse control, but that button at the handle pivot is your neutral only button. Put it in neutral, then either push or pull the button (Whichever works) and move the lever forward for throttle only.
If you pull the lever all the way back to neutral again, it will automatically return to throttle and shift.

 

[ctparks]

Re: Starts on land but not in water

That's an old Morse control, but that button at the handle pivot is your neutral only button. Put it in neutral, then either push or pull the button (Whichever works) and move the lever forward for throttle only.
If you pull the lever all the way back to neutral again, it will automatically return to throttle and shift.

Yea, thats exactly how it works too...I push the button and can go fwd, when i bring it back to neutral it pops out. I never knew that is what the button was for. That helps alot...Thanks!!! However before the overheat and all this started I never had to worry about moving the throttle any, it would crank right up in neutral on land or in the water.

 

[Don S]

Re: Starts on land but not in water

You were lucky.

 

[ctparks]

Re: Starts on land but not in water

You were lucky.

It still will crank on land without any movement of the throttle...I just need to give it a little gas on the carb once it fires off while sputtering to get it stable at idle. So in the water how much throttle should I give it while cranking??