Cooling water pathway on V4 looper.

[sutor623]

Trying to get an idea exactly how the cooling water flows on the V4 loopers. I am working on getting some pics up right now.

 

[sutor623]

Here is the cooling pathway from the factory manual. What happens at the Y where the input line comes into the midsection? How does the water split off to two sides?


Water goes into the powerhead via the two sides where it is marked blue:


Then up up to where the rectifier sets:


Cooling the exhaust ports from the cylinders (and warming the water):


Then the water makes its way back down to the bottom of the cylinders:


Comes in to the water jacket around the cylinders and works its way up to the thermostat:


Then, comes through the thermostat when the temperature is correct (or through the poppet valves under high pressure):


Then goes out the bottom of the head (marked in red):


Then comes out the bottom of the block on both sides (where it is marked red):


Going down the leg and out the exhaust vents and prop.


Does this look correct?

My Questions are as follows:

1.) How does the water Y off from the input line? Is it just a casting in the exhaust housing?

2.)Is photo 4 correct? Are those the exhaust ports from the cylinders?

3.) Does that cavity (under the rectifier) fill completely up with water? Does the water travel in and up, then back down to enter the bottom of the cylinder water jacket?

Thanks guys. I also hope this helps anyone wondering how the cooling system works on these motors.

 

[David Young]

I can't help you but it shows 'me' how important the 'little impeller' (water pump) is.

 

[bob johnson]

I think water goes everywhere it can because of backpressure..... the amount of water VS the size of the final exit , creates a bottleneck and the water just "fills" every place it can, which included up to the rectifier... if there wasn't a back pressure situation going on...you could not "shoot" water out the tell tale like you do!!!

I think about what might be my issue and I see that the only screening in the system is the water intake screen... and I think "stuff" gets in and gets pumped through the motor...I know algae and weeds have choked my motor out so much the temps sent my alarm off once...(that's like 220 or more degrees!!)......

look at all those nooks and crannies!! and rough casting surfaces...I think "stuff ' could get hung up and cause blockage...it might be like you suggested once...if there is blockage on one side....its a double wammy, because you have too little water to cool that side , AND you have all the extra water cooling the other side....

because the water is going to flow!!!!!

bob

 

[sutor623]

That's right buddy!! But I learned something GREAT about these motors by breaking it all down like this(these are just pics from the net, not my motor). If you pull the heads, the rectifier, and lower unit, you have access to ALL of the water passages. It seems that there are 3 possible places for hangup/blockages in the powerhead. One is where the water comes in the water jacket at the bottom of the cylinders, two is the thermostat, and three is the port that leads out from the bottom of the head and down the block. I wonder if my and your motor has a hangup or a small casting issue at one of the places causing the motor to heat up more on one side.................

 

[bob johnson]

That's right buddy!! But I learned something GREAT about these motors by breaking it all down like this(these are just pics from the net, not my motor). If you pull the heads, the rectifier, and lower unit, you have access to ALL of the water passages. It seems that there are 3 possible places for hangup/blockages in the powerhead. One is where the water comes in the water jacket at the bottom of the cylinders, two is the thermostat, and three is the port that leads out from the bottom of the head and down the block. I wonder if my and your motor has a hangup or a small casting issue at one of the places causing the motor to heat up more on one side.................

our motors are different casting designs, the eagle blocks (60degree loopers ) had holes in the block around the cyiliner bores...not a huge contiuous void...I think it would be easier to get something caught in a block like mine than like yours!....on the v4 I am rebuilding , Ill run some wire through all the passages before I reassemble. But I wont be taking my current motor apart to do the same!!!! good luck

bob