Mercrusier 3.0 radiator flush ??

Hey guys, the rookies back.
Ive just bought a 19ft 87 sportsman craft half cab with a mercruiser 3.0 with alpha one leg.
Just got her home yesterday and am eager as hell to tackle the learning curve to save thousands.

The guy i bought it from said shes reasonably ready to go but recomends a service ( of course ) new fluids, water pump impeller ect.

Im competent working on cars which is why i opted for an inboard that needed work rather than an outboard..not sure how wise that is but im here now.
So my question;...s

How do i flush the radiator ? I just want to clear out gunk not winterise, is it that differnt to a car ? ( detach lower hose and jam a hose in the resivour ) and which hose(s) do i disconnect ?

Where do i find the water pump to rebuild/install the impeller ? Ive got a kit and ive spent 30 mins looking for something that looks the same to no avail.

Also a bit of cleaning advice.. ive got a can of linox and hose in hand for now, there is a bit of corrosion here and there around the motor and rust. I know its probly not great but is it fine to hose down ( maybe wipe down aswell ) and then empty the can of linox on the motor ?
Also while hosing is there places i should be cautious of hitting with the jet ? Beside the dizzy/coil of cause.

And lastly, ive been advised to re set the points and i havnt even done something like that in a car so what am i getting into here ? Any advice/wisdom would be appreciated.

Thanks for your time guys, im going to go fiddle while i wait : )

Radiator?

Docksidemarineservices said:

Radiator?

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Yeah, could be spelt wrong or not the right name but it has a resivour and hoses on the inboard filled with coolant and a similar cap to that on the radiator in a car.

Not sure if you would call it a fresh water or internal or whatever.. im new to boats even if it was an outboard ha ha inboard this is the first time ive even looked at one

Ayuh,.... Closed coolin' is fairly rare on a 3.0l Merc,... Might be aftermarket,...

They usually gunk up on the raw water side, not so much the coolant side,...
There should be end caps that can be removed to clean out the raw water side,...
In freezin' weather, the raw water needs to be drained so it don't freeze, 'n bust stuff,...

The impeller is on the top of the lower unit of the outdrive,...

Buy a manual! And study it thoroughly. That's how to come up to speed on these things, that are a LOT different than cars.

Jeff

Are you sure its a 3.0 Ltr and not a 3.7 Ltr? Maybe you should post a picture of your engine.

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Mouse said:

How do i flush the radiator ?
I agree with the guys....... this may not be a GM 3.0L engine, and is perhaps the dreaded Merc 3.7L engine.

Post a few photos of this engine.

If both the Intake and Exhaust are on the Port side...... it will be the GM 3.0L < click here!

If the Intake is Port side and the Exhaust is Stbd side...... it will be the Merc 3.7L < click here.


I just want to clear out gunk not winterise, is it that differnt to a car ?
Yes.....
Marine Engines that incoroprate a "Closed Cooling" system use what's called a "Heat Exchanger".
The H/E uses seawater to pull the BTUs from the Ethylene Glycol (aka engine coolant), as apposed to air pulling the BTUs as in a car/truck "Radiator" scenario.

detach lower hose and jam a hose in the resivour ) and which hose(s) do i disconnect ?
I am with the guys here...... pick up a year/model correct OEM Owners Manual....... NOT Seloc and NOT Clymers...... OEM ONLY!

Where do i find the water pump to rebuild/install the impeller ?

That would be your "Seawater" pump.
We DO NOT install a new impeller until just prior to the new season!
(there is no reason for several impeller vanes to be folded over during the lay-up!)

And keep in mind that a dry start can ruin an impeller in just a few seconds!

Ive got a kit and ive spent 30 mins looking for something that looks the same to no avail.
The Merc A drive seawater pump is inside of the lower gear unit.
Like suggested....... get yourself an OEM Manual.

Also a bit of cleaning advice.. ive got a can of linox and hose in hand for now, there is a bit of corrosion here and there around the Engine and rust. I know its probly not great but is it fine to hose down ( maybe wipe down aswell ) and then empty the can of linox on the Engine ?
Also while hosing is there places i should be cautious of hitting with the jet ? Beside the dizzy/coil of cause.
Yes...... and it may be best to have a Marine Mechanic perform this work.


And lastly, ive been advised to re set the points and i havnt even done something like that in a car so what am i getting into here ? Any advice/wisdom would be appreciated.
Again............., please, please, please pick up an OEM service or work shop manual in addition to an owners manual.

The kettering system (contact points) requires a dwell angle to be set.
Dwell Angle is the measure of degrees in which the points are closed which in turn saturates the Ignition Coil.
NOTE: adjusting the Point Gap is an estimate ONLY of correct dwell angle!
Use a Dwell Angle Meter!

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