Suzuki 4 stroke 4hp outboard, 2007.

[rotrax]

Returning from the mooring last Monday I noticed no water stream from the telltale.

The engine was commisioned in July 2007 and untill 2015 had had less than 2 hours running-the previous owner kept a log. I checked and serviced it in 2016, again in 2017 and again at the start of this season. It had always been faultless.

Anyway, fetched it home, pulled the gearcase off and inspected the impeller-looked perfect. Cleaned it all up, put the impeller back in-checking it was properly located on its drive key-refitted the gearcase and started the engine, good output from the telltale. Stopped the engine, greased and lubed a couple of pivots and the tilt lock, restarted the engine.

No output from the telltale! I am running it in a full dustbin of water, so the intake is well submerged.

Before I start chasing shadows, any direct experience on here with similar problems?

The re-used impeller required a prod on the tips to fit back into the pump housing and I did expect it to be springy enough to work-next step will be to change it I expect.

I fitted a rubber pipe on the water pipe that transfers water up to the engine and blew through-no resistance and could hear the displaced air in the exhaust. The pee hole is also clear. As a matter of course the engine is run in fresh water every time we return to the outboard store at our club mooring, so I dont think salt build up is an issue. I doubt it has run 12 hours since it was new. Longest single run was Dittisham-Totnes and back this year, 2 hours total, and completly trouble free.

Any help gratefuly recieved.

 

[seaangler23]

I've got mine in bits just now cause of the same issue, mine was a 2008 and spent its life on the back of a hawk 20 so never flushed out and so it's fairly rotten inside, seems mine is due to corrosion and salt build up, try poking some thing up the telltale hole, or better compressed air, could be something simple, the next step would be take the thermostat out for a look, but it's a pain as its on the same gasket as the inlet and breather so it will break and you'll need to replace it.
Could try rigging a drip up to it through the telltale hole, I've used Coca Cola a few times if it's a salt build up, but think there are better solutions out there

 

[gordmac]

Can you see if water is coming out the exhaust?

 

[rotrax]

Can you see if water is coming out the exhaust?

I have used a hose and sent water up the transfer tube-it comes out down the inside of the leg, which is the exhaust. When running in the dustbin, water spray can be seen from the telltale hole, but not very much.

What is confusing me is that immediatly after putting it back together it worked fine. After stopping and restarting, zilch!

I shall order an impeller tomorrow-see what fitting a new one does.

Thanks.

 

[Keith-i]

There is still a chance the 'pee' hole has a blockage. When you piped water up the transfer tube there probably would not be enough pressure to dislodge anything in the pee hole as most of the water would exit via the exhaust. Have you disconnected the pee hole rubber tubing where it connects to the block? You could also try back flushing via the pee hole perhaps with a syringe of water.

 

[rotrax]

There is still a chance the 'pee' hole has a blockage. When you piped water up the transfer tube there probably would not be enough pressure to dislodge anything in the pee hole as most of the water would exit via the exhaust. Have you disconnected the pee hole rubber tubing where it connects to the block? You could also try back flushing via the pee hole perhaps with a syringe of water.

A prod with a length of welding rod told me the pee hole is clear-first thing I did. I will look further, but the pee hole connection is internal and it looks like the power head needs removing to get at it.

Thanks.

 

[VicS]

I have used a hose and sent water up the transfer tube-it comes out down the inside of the leg, which is the exhaust. When running in the dustbin, water spray can be seen from the telltale hole, but not very much.

What is confusing me is that immediatly after putting it back together it worked fine. After stopping and restarting, zilch!

I shall order an impeller tomorrow-see what fitting a new one does.

Thanks.

The water level in the dustbin should cover the location of the water pump, ie an inch or so above the joint between the top of the gear case and the exhaust housing

You should see a spray or mist from the exhaust back pressure relief port on the back of the exhaust housing if all is well. If you see this but are getting no flow from the tell tale then the latter is probably blocked

Are there any indications that the engine is overheating ? Steam from the relief port or telltale ? Discolouration of paintwork? Too hot to maintain brief finger contact with any part of the cylinder block or head, except perhaps around the spark plug?

 

[rotrax]

The water level in the dustbin should cover the location of the water pump, ie an inch or so above the joint between the top of the gear case and the exhaust housing

You should see a spray or mist from the exhaust back pressure relief port on the back of the exhaust housing if all is well. If you see this but are getting no flow from the tell tale then the latter is probably blocked

Are there any indications that the engine is overheating ? Steam from the relief port or telltale ? Discolouration of paintwork? Too hot to maintain brief finger contact with any part of the cylinder block or head, except perhaps around the spark plug?

No- the run to and from our mid harbour pontoon is barely a minute. I have been careful when testing not to run it too long, so no evidence of overheating. The paint on the engine looks like new, even around the plug.

As I mentioned earlier, a very fine spray-just wets a dry fingertip after a few seconds-does come from the pee hole. Exhaust pressure can be felt there too.

There is no easily seen connection from the engine head/cylinder for the pee hole. If there is a connecting pipe in there, it is possible it is detatched. It could well be working, but unseen from the exterior.

I'll get there in the end, I'm sure!

 

[gordmac]

Is it worth running it in a bucket of some sort of salt dissolver or vinegar?

 

[rotrax]

Is it worth running it in a bucket of some sort of salt dissolver or vinegar?

No- as I have said, it has run less than 12 hours since it was commisioned and I have always run it in fresh water at every opportunity. Salt build up is not the problem I am certain.

Thursday it was perfect, Monday when returning from the mooring, strong output from the pee hole, suddenly half way home, ziltch.

Salt build up would have been slow, not almost instant.

 

[VicS]

No- the run to and from our mid harbour pontoon is barely a minute. I have been careful when testing not to run it too long, so no evidence of overheating. The paint on the engine looks like new, even around the plug.

As I mentioned earlier, a very fine spray-just wets a dry fingertip after a few seconds-does come from the pee hole. Exhaust pressure can be felt there too.

There is no easily seen connection from the engine head/cylinder for the pee hole. If there is a connecting pipe in there, it is possible it is detatched. It could well be working, but unseen from the exterior.

I'll get there in the end, I'm sure!

There is no pipe. The "pilot water hole" is located in the flange at the top of the drive shaft housing discharging directly from the water channel within this flange. Basically, IYWF, directly from the water tube delivery to the power head. ( See below)

If there is no flow from here it is either blocked ( but that's easily sorted with a bit of wire shoved into it) or the water pump is not delivering water to the power head.

If there is no water flow through the power head you will get exhaust gas blowing backwards through the cooling system and out of the pee hole. You have observed this I believe.

It might be a good idea to screw in the hose connector than can be used to flush a non running engine and give it a good blast through with fresh water checking that water comes out of the exhaust outlet, the pee hole and some from the water inlets.
When you drop the gear case off to investigate connect a hose to the water tube and be certain that water is peeing from the pee hole as well as from the power-head discharge into the exhaust.
Blowing air through system is little more than a waste of time.

 

[rotrax]

Thank you-got man flu at the moment. Soon as I get mended I'll get back on to it.