Hot water

[Monty 57]

Could putting too much anti freeze in affect the engine heating the water?

Used to get very hot water after about 2 hours cruising, Had a new water pump fitted tot he engine and now water hardly warm

 

any suggestions?

[Alan de Enfield]

 

Ideally 33% - 50%(max) antifreeze.

Antifreeze must be mixed in the water before putting it into the system.(Pre-Mix) If you put water in then anti freeze it will not mix and you won't get 'proper' heating.

[blackrose]

17 minutes ago, Monty 57 said:

Could putting too much anti freeze in affect the engine heating the water?

Used to get very hot water after about 2 hours cruising, Had a new water pump fitted tot he engine and now water hardly warm

 

any suggestions?

 

I'd suggest that fitting the new water pump is more likely to be the issue than the concentration of antifreeze.

 

Probably an airlock somewhere in the system.

Edited June 8, 2021 by blackrose

[dmr]

I suspect the system was partly drained down to fit the new pump and you now have an airlock.

 

...............Dave

[Jen-in-Wellies]

Almost certainly an air lock due to the engine coolant having been drained to fit the pump. There will be a pocket of air at a high point in the pipe and hose work between the take off from by the thermostat housing to where the coolant returns to the engine at, or near the water pump. Massaging the hoses can help work it through, or carefully partially removing the hose, or opening a joint at a high point to let any air escape. Only do this when the coolant is cold and unpressurised. Have the coolant filling cap off to stop it pressurising and giving the air somewhere to go. You can also get air locks in the main cooling circuit, assuming your boat is keel cooled, but if you had that problem the engine would have overheated by now!

 

I've fitted bleed points, using radiator drain down valves, to the high points of calorifier engine coolant circuits to make this easier on a couple of friends boats for them.

Jen

[Stilllearning]

Renault cars used to come with bleed valves fitted as standard, back in the day. It was such a good idea.

[Jen-in-Wellies]

If your boat is cooled by a skin tank, then it is possible that the tank is now no longer completely full after the engine coolant was partially drained and refilled. This could lead to overheating if the engine is run hard, say heading upstream on a river. On many tanks, there is a bleed point on top that can be loosened to let any air out. Watch the coolant level in the header tank, or filling opening and replace with pre-mixed antifreeze. If there is no bleed valve, then again, loosening the top hose with the engine running, but cool and the coolant cap off can get any air out, as can massaging hoses, assuming they are not the reinforced wire wound sort.

Jen

[rogerc]

if the side tanks are starting to heat before the calorifier is hot, there's definitely a circulation problem. i get hot water in half an hour from a 42HP engine

[nicknorman]

...and yet another question asked by a newbie, good answers given, but newbie can't be bothered to acknowledge or say thank you. Rude and entitled!

[bizzard]

I presume 57 is Monty's age, same as a tin of Heinz beans.