Impellor and cooling

[Mike B]

Dirk - please don't shout at me this may be a really simply question.

The cooling tell tale on my suzuki 55 2 stroke has practically stopped.

After running for a bit some water does splutter out the exhaust.

The engine has a rev limiter for overheating which is not triggering even after three hour near continuous use, so I am guessing the engine is at least cooling a bit.

I have already tried clearing out the tell tale hole and tube with wire.

Now for the question.

As the engine is running fine and the limiter not kicking in do I continue to run it until the engine is due for a service (January) and get the cooling circuit checked then ?

Or should I get it booked in now to have some investigations done?

How easy is it to check the impellor myself? (looking at the service manaual the most difficult bit appears to be disconnecting and reconnecting the gear linkage).

If I do book the engine in how much should I expect an impellor check / change to cost?

Thanks in advance

Mike

[Pete7]

Mike, before you take the leg off have a look at the termostat which is up stream of the cooling pipe. They do block up with salt eventually even if you flush with fresh water after every trip. You should be able to blow through the cooling tube. If not then replace it.

Removing the leg is straight forward. Top tip, by convention, put the engine in forward before starting. The seventh bolt is hidden under the trim anode which has to be removed to access it.

The water pump has a "key" don't loose it. Imprellors are cheap, if your going to remove the leg you may as well do the impellor and any gaskets anyway. Do a drawing of the direction of the imprellor BEFORE you remove it or it will really spoil your day fitting it the wrong way round. Time to change an impellor for the first time about 30 mins and I promise it is a solo DIY job.


Pete

[Bilge Rat]

Mike i had a simular problem to this 2 weeks ago, firstly the engine started cutting out while at sea and would start up again straight away with no apparent problems, then as it got worse the engine would not rev very high, back on the beach we first cleaned the fuel filter and pipes and checked the fuel pump, then ran the engine again with clean water going through, the powerhead was getting hot so we whipped out the thermostat and ran the engine again without the thermostat and with clean water running through it, it still got hot and the water comming through the pee hole was getting hotter, so we attempted to drop the lower leg and gave this up as a bad idea due to the fact we were on the beach, the boats at a friends now having the impellor changed out, after talking with people i've found out my engine has a clever cut out system when it gets too hot, this stops you destroying the engine and the drop in revs will give you enough to get you home slowly.

Good luck

Richard

[gavin]

As prerviously stated this is a diy job, before u do go to the bother of dropping the leg check everything else, are the inlets blocked for instance or is the cooling hose split just before the tell tale causing hot water to come out under the outboard hood,, the impellor is most likely worn it sometimes deteaches itself from the inner drive part and doesnt spin when the pump runs, causing no water etc , try unblocking the circuit, thermostat, test the stat in a pyrex glass full of boiling water then cool it and observe it close, rule out all this first cheers

[Mike B]

Many thanks, Pete, Richard & Gavin.

Looks like thats my Sunday taken care of.

Cheers

Mike