Is it critical if no water comes out?

[eddystone]

I have 2HP 2 stroke mariner; head end now works OK - but stopped passing water a while ago - is it possible water still circulating but getting lost somewhere else? the impellor is fine. Are there symptoms of overheating might spot before it seizes up|?

 

[Lakesailor]

You should be able to briefly touch the head without your skin falling off if it is not overheating. If it is overheating you will find the motor slowing and possibly stopping. It's not a big deal really. Scooters used to do it all the time.
It may just be the tell tale pipe is blocked. That is not a problem in itself. The main water exit is down the leg
If it's a 2hp, without the gearshift, the impeller is behind the prop. A couple of bolts and you can change it if you need to.


This is the pee pipe. It may be blocked or the union on the water jacket may be blocked. As you can see poking up the pipe won't get as far as the union. Just twizzle a twist drill between you fingers to remove any crud.
Did you clean out the water passage whilst you were doing the top end?

 

[30boat]

Get a cylinder head gasket and clean the waterways.It's an easy job.Make sure the head is flat.If it seizes it can damage the piston and liner,not worth it.I should be done regurlarly anyway.

 

[Storyline]

There was a recent thread about this assuming that you mean that it is the telltale that is not sending out water. This must be the case or else your outboard would seize very quickly if there was no water circulating.

I have the same problem with my Tohatsu 2 stroke 5hp. I have no idea of how the water circulates in outboards like this so would be grateful if any outboard experts could explain how the cooling system works (assume that most must come out with the exhaust).

Anyone ?

 

[Lakesailor]

Get a cylinder head gasket and clean the waterways.It's an easy job.Make sure the head is flat.If it seizes it can damage the piston and liner,not worth it.I should be done regurlarly anyway.

The more important waterways are those between the powerhead and the leg.


The arrows show where they are. The two arrows on the right show where the water passage narrows to go through to the head. Apart from cleaning them out, I slightly enlarged them to ease the flow. Not too much as it may effect the scavenging.

 

[30boat]

There was a recent thread about this assuming that you mean that it is the telltale that is not sending out water. This must be the case or else your outboard would seize very quickly if there was no water circulating.

I have the same problem with my Tohatsu 2 stroke 5hp. I have no idea of how the water circulates in outboards like this so would be grateful if any outboard experts could explain how the cooling system works (assume that most must come out with the exhaust).
Anyone ?[/QUOTE
Couldn't be simpler.There's a pump at the leg or behind the prop that sends water up to the head and cylinder via a copper pipe.It goes around the water jacket and head and exits into the leg downwards of the exhaust port.

 

[30boat]

The more important waterways are those between the powerhead and the leg.


The arrows show where they are. The two arrows on the right show where the water passage narrows to go through to the head. Apart from cleaning them out, I slightly enlarged them to ease the flow. Not too much as it may effect the scavenging.

Dirty little things aren't they?

 

[TQA]

With the engine running in water poke a bit of wire up the pee hole and wiggle it about.

This fixes it most times if it has not been allowed to run this way for years.

11 years of bodging outboards as a full time anchor out liveaboard.

 

[TQA]

With the engine running in water poke a bit of wire up the pee hole and wiggle it about.

This fixes it most times if it has not been allowed to run this way for years.

11 years of bodging outboards as a full time anchor out liveaboard.

 

[Storyline]

There was a recent thread about this assuming that you mean that it is the telltale that is not sending out water. This must be the case or else your outboard would seize very quickly if there was no water circulating.

I have the same problem with my Tohatsu 2 stroke 5hp. I have no idea of how the water circulates in outboards like this so would be grateful if any outboard experts could explain how the cooling system works (assume that most must come out with the exhaust).
Anyone ?[/QUOTE
Couldn't be simpler.There's a pump at the leg or behind the prop that sends water up to the head and cylinder via a copper pipe.It goes around the water jacket and head and exits into the leg downwards of the exhaust port.

Thanks
So there is absolutely no problem if the telltale shows no water other than the fact that it is not telling you that there may be a problem ?

 

[30boat]

Thanks
So there is absolutely no problem if the telltale shows no water other than the fact that it is not telling you that there may be a problem ?

I would try to clear the tell tale hole to see if water would come out.In case it didn't I'd monitor the motor's temperature carefully.

 

[landlockedpirate]

Thanks
So there is absolutely no problem if the telltale shows no water other than the fact that it is not telling you that there may be a problem ?

If the tell tail isnt working then you do have a problem. You need to investugate to find out how bad the problem is, from a simple blocked tell tail to a full cooling system failure. Here is mine, good strong water jet even at idle.

 

[Storyline]

Thanks Mark.

That is certainly the same engine as mine, even down to the 4hp sticker even though mine has been converted to 5hp (which cost the princely sum of £15 !)

I got the engine s/h but it had less than 10 hours on it. The telltale never worked as well as yours but over the past year or so has dried up completely. I have a harness on the cowling as I use it with a deck crane and this used to sometimes interfere with the rubber tube so maybe that has something to do with it.

Had it professionally serviced last year and he replaced the impeller and at the time he commented that the telltale was not working. He ran out of time so did not fix it but I am fairly sure he had a quick look so it is nothing obvious. At the end of the season I will see if I can see anything but failing that will get my (excellent but not bargain basement !) yard to sort it as I would like to have it.

 

[landlockedpirate]

Thanks Mark.

That is certainly the same engine as mine, even down to the 4hp sticker even though mine has been converted to 5hp (which cost the princely sum of £15 !)

I got the engine s/h but it had less than 10 hours on it. The telltale never worked as well as yours but over the past year or so has dried up completely. I have a harness on the cowling as I use it with a deck crane and this used to sometimes interfere with the rubber tube so maybe that has something to do with it.

Had it professionally serviced last year and he replaced the impeller and at the time he commented that the telltale was not working. He ran out of time so did not fix it but I am fairly sure he had a quick look so it is nothing obvious. At the end of the season I will see if I can see anything but failing that will get my (excellent but not bargain basement !) yard to sort it as I would like to have it.

If the engineer isnt worried, it should be fine. Mine was uprated free of charge when I bought it new from Bill Higham. At the time he told me he uprated most of the 4hp's that he sold.