M/C 470 Getting Hot

[a1nowell]

My 470 is getting hot. I have it in the driveway. Stern is in a tub of water with the prop off. I started it up and removed the seawater hose at the exhaust elbow, there is no water coming out but there is exhaust coming out from the fitting where the seawater should flow into. Whats going on??

 

[zbnutcase]

Re: M/C 470 Getting Hot

You need a waterpump job in the drive. AND DO NOT LET THAT ENGINE GET HOT!!!! All kinds of bad things happen when those overheat

 

[a1nowell]

Re: M/C 470 Getting Hot

What would cause the exhaust to be coming out of the connection at the exhaust elbow where the sewater should be flowing into?

 

[zbnutcase]

Re: M/C 470 Getting Hot

Exhaust gases in the elbow entering the cooling system since there is no water flowing OUT of the system

 

[stonyloam]

Re: M/C 470 Getting Hot

You should probably use a hose and muffs rather than the tub. As I understand it the impeller housing must be below the water level, just having the intake below the surface is not enough. If it ran dry, you will need a new impeller. At this point I would replace the impeller and housing. Good luck.

 

[EddiePetty]

Re: M/C 470 Getting Hot

...... I started it up and removed the seawater hose at the exhaust elbow, there is no water coming out but there is exhaust coming out from the fitting where the seawater should flow into.

.....well now, if you have un-cooled exhaust gases into the riser and out the lower unit, please inspect the exhaust passages for a burned-up exhaust flapper(shutter).

...also, don't even think about replacing simply the pump's impeller. Replace the complete pump: more than likely it's a melted puddle of plastic.

 

[joel2899]

Re: M/C 470 Getting Hot

I had the same problem and found my wet exhaust manifold to be plugged with rust and build up i cleaned it out and that solved the problem

 

[a1nowell]

Re: M/C 470 Getting Hot

Joel,
The "wet exhauste manifold" are you talking about the exhaust elbow?

 

[Bifflefan]

Re: M/C 470 Getting Hot

I started it up and removed the seawater hose at the exhaust elbow, there is no water coming out but there is exhaust coming out from the fitting where the seawater should flow into. Whats going on??

There is no water flowing throught the sea water side.

Joel,
The "wet exhauste manifold" are you talking about the exhaust elbow?

If you pulled the hose at the riser and no water is coming out, the riser is not the problem.
Check the hoses from the transom forward. Remove each and inspect them. one may colapsed. Check the regulator, its water cooled and has small holes for the water to flow through. Pull the end caps off the heat exchanger and look inside it. Also look in the inlet in the bottom of the drive for old impeller pieces or other stuff.
If all that is good, then the hose inside the gimble houseing is most likely clogged. You have to pull the drive and bell housing to fix this. You may as well to the bellows at the same time as you must remove them also to get to that hose.

The blue lines are what your looking at.