no water! - it isnt the impeller

[VicS]

I have ordered one.


I cleared the holes in the cooling block but did not check the actual exhaust. Do you mean here?


Next time I'm open the boat I will...
Check the exhaust
Fit the thermostat
Run acid cleaner through the engine on a loop

Thanks Vic and everyone else. It is very much appreciated.

S

Yes and right through the exhaust outlet elbow and into the exhaust gas stream

Not sure what you mean by the "cooling block" though.

The trouble with trying to clean a cooling system like this with acid is that if any parts are completely blocked the acid wont get to them and they don't therefore get cleaned.

 

[PaulRainbow]

Yes and right through the exhaust outlet elbow and into the exhaust gas stream

Not sure what you mean by the "cooling block" though.

The trouble with trying to clean a cooling system like this with acid is that if any parts are completely blocked the acid wont get to them and they don't therefore get cleaned.

That's the point of the Rydlyme that was discussed earlier, it goes round and round for 2 or 3 hours and clears everything it touches. It won't do the exhaust elbow, because the pipe going to that has to go back to the bucket of Rydlyme, but that can be manually cleaned, then soaked in the bucket whilst it's circulating.

 

[stu9000]

Not sure what you mean by the "cooling block" though.

.

My bad. I mean to say the exhaust manifold.

 

[stu9000]

What I still don't get is if the thermostat is not there=the engine running cool.
Should it not be the other way around?

If I have this right when the stat is open it follows the red path, otherwise it goes the long route through the engine cooling channels.
.


If there is no thermostat present surely the short cut route is open, so the engine isn't being cooled = running hot.

The blue arrow just indicates cold water being pumped towards the engine. There is a pipe half way along that blue line feeding into the engine without going via the thermostat. This seems counter intuitive but perhaps even a cold engine needs some water flowing around it. Either that or I still have a lot to learn

 

[chewi]

What I still don't get is if the thermostat is not there=the engine running cool.
Should it not be the other way around?

If I have this right when the stat is open it follows the red path, otherwise it goes the long route through the engine cooling channels.
.
View attachment 70555

If there is no thermostat present surely the short cut route is open, so the engine isn't being cooled = running hot.

The blue arrow just indicates cold water being pumped towards the engine. There is a pipe half way along that blue line feeding into the engine without going via the thermostat. This seems counter intuitive but perhaps even a cold engine needs some water flowing around it. Either that or I still have a lot to learn

no thermostat provides no controlled blockage so cooling circulates even when engine is cold.
hence engine runs colder than it should.
with thermostat the engine passage is blocked in favour of the bypass until the engine gets warm, then the thermostat opens and allows coolant to engine... but only when needed.

 

[VicS]

What I still don't get is if the thermostat is not there=the engine running cool.
Should it not be the other way around?

or I still have a lot to learn

Yes you seemed to have failed to understand the circulation, despite the diagram in the manual

Cold water flows directly into the engine at two points, one near the back of the manifold and one via the bottom connection on the thermostat housing. The thermostat does not control the cold water entering the engine, it controls the hot water leaving ( just as the thermostat in your car engine controls the hot water flow from the engine to the radiator).

When the engine is cold the thermostat is closed . No water leaves so effectively no water flows through the engine.

When the engine reaches its operating temperature the thermostat opens to allow hot water to leave, then of course you get a flow through the engine. Cold water entering directly and hot water leaving via the thermostat.

The hot water flows along the line of the red arrows to the exhaust outlet elbow

AS WELL AS this flow through the engine there is also a flow through the bypass in the thermostat housing. This flows even when the thermostat is closed, bypassing the engine and the thermostat, in order to cool the exhaust whlie the engine is warming up, other wise the exhaust system would burn up in the period before the thermostat opens

I have added more detailed colouring to the water flow diagram in the hope that it will help.

 

[stu9000]

Yes you seemed to have failed to understand the circulation, despite the diagram in the manual

Cold water flows directly into the engine at two points, one near the back of the manifold and one via the bottom connection on the thermostat housing. The thermostat does not control the cold water entering the engine, it controls the hot water leaving ( just as the thermostat in your car engine controls the hot water flow from the engine to the radiator).

When the engine is cold the thermostat is closed . No water leaves so effectively no water flows through the engine.

When the engine reaches its operating temperature the thermostat opens to allow hot water to leave, then of course you get a flow through the engine. Cold water entering directly and hot water leaving via the thermostat.

The hot water flows along the line of the red arrows to the exhaust outlet elbow

AS WELL AS this flow through the engine there is also a flow through the bypass in the thermostat housing. This flows even when the thermostat is closed, bypassing the engine and the thermostat, in order to cool the exhaust whlie the engine is warming up, other wise the exhaust system would burn up in the period before the thermostat opens

I have added more detailed colouring to the water flow diagram in the hope that it will help.

View attachment 70557

Thanks Vic Makes more sense now

 

[stu9000]

It's fixed! Properly this time.

The problem was initially no water coming out of the exhaust.
This was solved by taking the exhaust manifold off and soaking it in brick cleaner.
I also ran a 50% water and brick cleaner through the engine on a loop for about 40minutes which improved water flow further.

Although there was now water flowing the engine was still getting hot. No alarms but lots of white smoke/steam after running for a few minutes.

This problem was a result of the cleaning unblocking the gunged up thermostat housing. I fitted a new thermostat and the engine is now running well without smoke.

It has taken some time but I have learned a lot.
Thanks for the valuable and extremely useful advice.

S

 

[stu9000]

 

[[163233]]

What do people do with the used acid after flushing the engine?

 

[VicS]

What do people do with the used acid after flushing the engine?

They dispose of it responsibly by neutralizing the remaining acid with sodium carbonate and then washing it down the drain !