Force 50 HP Cooling passages Blocked

[divco13]

Anyone have a Diagram of the water Passages. For a 50 HP two cylinder motor

When replacing the Impeller, in the water pump housing. I tryed to blow air up the water tube water tube to the head. It was blocked. Took the thermostat housing off, and the Head was plugged. Dug out the crud, and got a fair amount of air to flow.

Don't want to R&R THE HEAD IF I DON'T HAVE TOO.

Is there a solution that I can run thru the water passages, to get the rest. The best part there was no Thermostat, just the spring.

I'm guessing someone removed the stat in order to find out why it was getting hot, or they thought it was bad. Or for some other dumb *** reason. Do not think it hurt the motor as it idles smooth

Bob

 

[pnwboat]

Water comes up to the adapter plate attached to the bottom of the block, then flows up through the exhaust cover to the top left side of the block. Then it flows down the left side of the water jacket around the cylinders, then up the right side of the water jacket around the cylinders to the thermostat, then down the water passage on the head and gets dumped out into the exhaust stream in the exhaust tube.

Here is a picture of the flow in a 4 cylinder. It's the same as your 50HP two cylinders. The passages in the exhaust cover are the most common area for blockage since they are much smaller than anywhere else. Disregard the water pressure relief valve. It's not present on your motor.

 

[divco13]

Thank yo for your reply. pnwboat
I also found a picture for a 2 cylinder on Goggle

What is best for loosening up salt deposits in the water jacket's.

 

[jerryjerry05]

You might get lucky and get a small amount out with the solvents and a flush??
Probably not much.
You'll need to remove the water jacket and head to see how bad it really is?

I've tried various ways over the years but a screwdriver or an awl works best.

Be VERY careful when removing the bolts on the exhaust. They are 1/4-20 and will twist off just looking at them.

I use a hammer, PB Blaster/ WD-40 and a torch.
Start spraying and heating and tap on the screws.
Then repeat. If you can't remove and break one off the fix can be done at a machine shop.

 

[pnwboat]

I've had pretty much the same experience as Jerry. Chemical flushes do little as far as removing the deposits like what you're seeing. You have to open up the passages by physically scraping the crud out.

I second the caution that Jerry mentions regarding the 1/4 X 20 bolts that hold the exhaust cover on. They're easy to break off. Not a show stopper but just another problem to deal with.

 

[divco13]

You might get lucky and get a small amount out with the solvents and a flush??
Probably not much.
You'll need to remove the water jacket and head to see how bad it really is?

.


Who on line is best for, older Force 50 engine parts seeing I'm pilling the head off.

And will be in need of a Head gasket a least

Bob

 

[pnwboat]

Not sure what year your motor is, but I assume it's around a 1989. IBoats should have the two exhaust cover gaskets, but they don't have the head gasket. Try these folks out for the head gasket. http://www.crowleymarine.com/mercury-outboard/parts/1307_90.cfm?mdl=CPDLMW

 

[tommarvin]

www powerheadkit.com
Don't get bummed out when you snap bolts off, a guy on here said you'll snap off one out of five bolts. you can drill them out yourself, if you don't have money to pay the shop, like the guys above let the shop do it if you can.

 

[jerryjerry05]

This site has parts.
​Or I use e-bay a lot.
E-bay's return policy is realllly good.
It used to be an iffy proposition buying there but not any more.

 

[divco13]

No Title

Here is a follow up of my Force 50 plugged water passages.

These are pictures of the deposits in the water jackets. Picture 3 is the water pressure tube from the water pump, before cleaning.
Pic 2 is the back side of the cylinder head, with a cup of some of the crud removed.

Does any one have knowledge of what. the deposits are, Does not taste like salt ! Yes I tasted it !

Thanks again for all the help
Bob

https://www.facebook.com/Divco-Milk-Truck-102362503162366/

 

[pnwboat]

That's just corrosion built up for many years of use. Sure looks like salt water corrosion. I don't know for sure...never tasted salt water corrosion LOL! One thing is for sure, you should have better water flow after you're done.

 

[divco13]

That's just corrosion built up for many years of use. Sure looks like salt water corrosion. I don't know for sure...never tasted salt water corrosion LOL! One thing is for sure, you should have better water flow after you're done.

There must have been over heating problems, at one time, as the thermostat was removed at one point

Yes this was used in brine water on the inter coastal rivers.

 

[divco13]

That's just corrosion built up for many years of use. Sure looks like salt water corrosion. I don't know for sure...never tasted salt water corrosion LOL! One thing is for sure, you should have better water flow after you're done.

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The material in the cup is a white paste, not hard or crusty

 

[jerryjerry05]

You ever cut a water pipe at home and have the calcium buildup in the pipe?
​That's what's in the cooling passages.
In time the white paste would turn hard and you'd have a calcium buildup.
Mineral deposits.
What' is pic #4

​It's bad enough you should take the head off and clean the cooling jacket/passages.

 

[divco13]

I was thing it was Calcium also, I have the Exhaust cover soaking in CLR, we'll see what happens !

#4 is ​cleaned Block Passages

Link below to web site that, has every thing I needed !

https://callisto.hmdnsgroup.com/~maxrules/fixforcegasket.html#1691_1

 

[jerryjerry05]

Your link wouldn't open??