heron
Well-Known Member
Have had some vague advice as to how to do this, but can anyone be more specific as to where I take the feed off from the engine and where I plumb the return feed back into the engine etc ? Its an 1997 5.7 V8 210hp.
Plumbing a calorifier in to a Mercrusier 5.7 V8
- Thread starter heron
- Start date
spannerman
Well-Known Member
If it has a spare tapping on the thermostat housing 3/8" NPT (for temp alarm sensor if not fitted) you can take the hot water out from there. You need to make up a T fitting on the hose going into the circulation pump for the return.
The hoses to the calorifier must not be larger than 5/8" dia and the calorifier should be lower than the filler cap if its a closed cooling system (feshwater).
The hoses to the calorifier must not be larger than 5/8" dia and the calorifier should be lower than the filler cap if its a closed cooling system (feshwater).
heron
Well-Known Member
I don`t think there was any tappings on the thermostat housing, someone else did mention that a while ago then sugested the pump. Its raw water called so the feed to the pump is under pressure from the pump in the outdrive , alpha 1. Is that going to cause any problems ?
alb40
Well-Known Member
Have helped a friend do this on a volvo 5.7 V8, which is probably the same block.
You will need to be a hose tail into the left side of the engine mounted water pump which is just below the thermostat housing. There is a blanking plug on there with a square head.
The other fed goes to another hosetail put into the base of the block. There are two drain plugs, one either side, which can be used.
Dont know what sizes they are off the top of my head. This was on a raw water cooled engine but it works quite well. If yours is fresh water cooled it will probably be the same still. Note that we had to replace the engine water pump though as the plug had siezed in place, so it was easiest to buy another one and put it on rather than muck about drilling it out. Half hour under power and plenty of hot water!
Hope this helps you out!
You will need to be a hose tail into the left side of the engine mounted water pump which is just below the thermostat housing. There is a blanking plug on there with a square head.
The other fed goes to another hosetail put into the base of the block. There are two drain plugs, one either side, which can be used.
Dont know what sizes they are off the top of my head. This was on a raw water cooled engine but it works quite well. If yours is fresh water cooled it will probably be the same still. Note that we had to replace the engine water pump though as the plug had siezed in place, so it was easiest to buy another one and put it on rather than muck about drilling it out. Half hour under power and plenty of hot water!
Hope this helps you out!
DavidJ
Well-Known Member
While you're doing the job you may want to consider some temperature regulation. The engine water temp is near boiling and by the time it's heated the calorifier the domestic water output is still scalding hot. I've not done this myself but I believe Broom's have this useful addition. Maybe this post will spark off some more informed comments.