Water cooling a 12HP air cooled motor

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liveaboard
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Re: Water cooling a 12HP air cooled motor

Post by liveaboard » Tue Jul 02, 2019 4:44 pm

Holes will have 3/8" pipe plugs.
tapping water jacket.jpg
Angled holes with a hole saw; probably illegal tool use.
boring an angle with holesaw.jpg
Parts getting ready
parts on the boarkbench1.jpg
water jacket assembly.jpg
water jacket welded.jpg
this drive flange came with the motor but I had to add the collar and bore it to a press fit on the motor shaft
drive flange with press collar 2.jpg

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Re: Water cooling a 12HP air cooled motor

Post by liveaboard » Tue Jul 02, 2019 5:50 pm

armature drive detail.jpg
it was made to hold a hydraulic pump
motor end cap before cutting.jpg
Now it has better air flow
motor end cap after cutting.jpg
Press fit fan holder for the other end of the motor
fan and mount shaft.jpg
fan mount shaft motor end.jpg
Had to make a new cage for the longer fan; it ain't pretty but it should serve.
New fan in cage with serial number.jpg

spro
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Re: Water cooling a 12HP air cooled motor

Post by spro » Tue Jul 02, 2019 7:54 pm

Your build keeps on. It must be astounding to others too. Man ! I don't have the words.

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Re: Water cooling a 12HP air cooled motor

Post by liveaboard » Wed Jul 03, 2019 5:17 pm

Thanks; the truth will be in the pudding of course; I won't know if it will work until I get it installed and buy batteries.

spro
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Re: Water cooling a 12HP air cooled motor

Post by spro » Wed Jul 03, 2019 7:01 pm

I was stunned by many of the operations. You clearly have a plan. Gosh I hope this works to your favor.

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Re: Water cooling a 12HP air cooled motor

Post by liveaboard » Thu Jul 04, 2019 1:03 pm

And far from finished! I need to make a cooling plate for the electronic control box, a jackshaft with a pulley and a gear, and fit a larger gear to the propeller flange from the boat, which I had mailed to me from Amsterdam.

And the jackshaft has to be movable to tension the belt.

Still plenty of fun before this is done.

rjitreeman0909
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Re: Water cooling a 12HP air cooled motor

Post by rjitreeman0909 » Fri Aug 02, 2019 9:28 am

Consider adding water tubing formed with 180 turns and each pass spaced as closely as possible to the previous. This will cover approximately 3/4 of the housing. Probably 2 or 3 assemblies with 5/16 or 3/8 diameter tubing paralleled together. In addition as you are working on, push as much air as possible thru the motor. May need to use more of a positive displacement blower rather than a fan since the air path thru the motor is quite small and will require head pressure to force the air thru. The addition of the water cooler end caps will also help. Good luck.

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Re: Water cooling a 12HP air cooled motor

Post by liveaboard » Fri Aug 02, 2019 3:29 pm

Did you see the pictures?
It now has a water jacket and a big cage fan from a 1/2 hp blower.
I considered tubing; it would be better for corrosion, but would have had t be brazed or soldered to the case to get decent heat transfer.

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Re: Water cooling a 12HP air cooled motor

Post by liveaboard » Sat Aug 03, 2019 1:46 pm

I made a 'throttle' box from a thing I had, some string, and a pot meter. the trick was to get the ratio right so the limited shaft movement results in the desired resistance change.
string guide knob on potmeter.jpg
Jackshaft with gear I took out of a junk car gearbox welded to a mild steel shaft.
sub shaft with gear.jpg
water cooling plate for the electronic control box
control box cooling plate.jpg
The field coil armatures are set with heat sink grease on the surface, copper grease on the screw threads, and permatex on the screw flanges
heat sink grease, copper grease, permatex.jpg
Pining up the jackshaft housing with the motor
laser lineup.jpg
pressure testing the water jacket
Attachments
water jacket pressure test.jpg

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Re: Water cooling a 12HP air cooled motor

Post by liveaboard » Sat Aug 03, 2019 2:30 pm

Pressing the fan shaft
pressing fan adaptor.jpg
additional connection bolts to make the motor reverse
Electric connection bolts.jpg
getting position
jackshaft setting.jpg
Jackshaft + belt
jackshaft mounted  with belt.jpg
Cutting a slot for the tensioner plate
slot cutting.jpg
'new' cage fan attached on the pressed shaft extension on the back.
Fan and connection bolts fitted.jpg

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Re: Water cooling a 12HP air cooled motor

Post by liveaboard » Sat Aug 03, 2019 5:44 pm

Made the instrument box; the power meter was just $25, + another 25 for a 500A shunt. the thermometers were $2 each, and I made a power supply for them from leftover electronic bits I had so they don't need batteries.
The boat has no cabin so this can be stowed below and only pulled up on deck when the electric motor is in use.
Testing on a 12v car battery but this will be a 48v system
instrument box with key switch.jpg
Temperature sender for the water thermometer
temperature sensor and water adapter.jpg
I soldered it
water temperature sensor installed.jpg
Sensor for the cooling air temperature; I made the holder from a bit of polycarbinate to insulate it from the metal fan cage.
air temp sensor + holder.jpg
I ordered 2 24V cooling pumps; they turned out to be a bit small! But I tested one and it works as advertised. One will be for raw water and the other glycol mix from the heat exchanger that's already in the boat for the diesel engine.
little 24v water pump.jpg
The pivot / mounting rod for the motor, and in the foreground a jig to clamp to the prop shaft flange to line up the rod before welding it in.
The motor will pivot up to disengage the gears when using the diesel engine.
I made a plate that unbolts from one end; basically, this is an installation kit so I can do the work at the boat quickly.
Pivot rod and alignment jig.jpg

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Re: Water cooling a 12HP air cooled motor

Post by liveaboard » Sat Aug 03, 2019 6:08 pm

the gears from a junk car, the pulleys + belts I bought new [gasp!] I had to get someone to go to the boat in Amsterdam and get the prop shaft flange out, and mail it to me here in Portugal so I could mount the big gear on it.
pulleys + gears.jpg
I realized that pinch bolt in a slotted plate isn't going to withstand the tension of that belt at power.
This is just a cool picture.
Well, maybe not 'cool' exactly.
tensioner 1.jpg
I used a couple of old headbolts I had, one I just cut and the other I used the belly to make a left-hand thread.
tensioner 2.jpg
The hex steel is some old scrap of unknown origin, and is very hard. It kills drill bits and has to be threaded with carbide. Cutting the 12mm internal thread was a challenge to my limited machining skill.
I'm confident this will hold the belt in tension.
tensioner 3.jpg

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