Serious cooling problem?

Have my Clymer's manual and the no. 2 manual from the manual website on this forum and have been trying to winterize and 'layup' and winterize my boat (302 ford model 888) for the months of Nov through Mar. Can't believe the recommendations...sure need to be mechanically inclined to own and maintain a boat! i.e. pull the spark plugs, insert 20 wt oil in the cylinder, ground the coil, turn over the engine for 15 - 20 seconds, replace spark plugs etc...remove rocker cover; liberally spray 20 wt oil on valve cover mechanisms, replace gasket and cover...egads...what have i got myself into???

Anyway, the current problem...am in the process of removing salt water from my closed cooling system...pulled the plug on the exhaust elbow...no water...tried to reinsert the plug...the threads are stripped (from previous owner...not me) bought a tap 1/8 pipe fitting and new plug. Cannot insert the tap...hole is blocked. My simple question is this...isn't the interior of the riser (exhaust elbow) hollow? Shouldn't i be able to insert tap...or is it that there is so much 'crap' the corrosive material that the riser is essentially 'shot'?

My conclusions are: 1) the riser is beyond hope and i should replace; the exhaust manifolds run antifreeze in them and shouldn't have to be replaced; 2) the fact that there was no water!!! is troublesome. Pulled the hoses from the Heat Exchanger (h/e) and found no saltwater in the h/e or in the hoses (just a trickle). Perhaps my impeller is also shot. The engine did, on a previous outing, get up to 200 degrees...then dropped to 150 or so. Has been running at that temperature for several outings.

Any thoughts...would appreciate the guidance of the many experts on this forum.

Re: Serious cooling problem?

sure need to be mechanically inclined to own and maintain a boat!

Click to expand...

Ayuh,... It's No different than a Car....
It's Still a complicated piece of Machinery...

1) the riser is beyond hope and i should replace;

Click to expand...

Ayuh,.. Sounds about Right,...
And,.. No, they're Not just Hollow,... It's a water Jacket...

Perhaps my impeller is also shot.

Click to expand...

That also sounds like a reasoable assumption...

Re: Serious cooling problem?

I too was having overheating problem with a boat I got last month. I started simple and went more complex. ie thermostat, impeller and exhaust elbow. Previous owner used boat in salt water so each step I found more and more corrosion/build up. When I first removed the t-stat I found it so eaten up with corrsion that it was not able to open or close. Some water was getting by. So at lower RPM it was running warmer than normal but would overheat at higher RPM. Changed the T-stat but still had overheating problems at higher RPM. Replaced impeller that was missing a blade but otherwise in good condition. Then I went to the exhaust elbow which was "caked" with corrsion/buildup. I cleaned up what I could see and reinstalled. Worked fine for approx 30 minutes then overheating again. I removed my exhaust manifold again "caked" with corrosion/build up. I soaked in CLR over night then flushed with water, removing a handful of stuff. While I had both off I decided to paint them. I have yet to install them but am confident the crap I removed from the elbow and manifold was the problem, causing a blockage in the system.

Re: Serious cooling problem?

jsurr, that rust you got out with the CLR used to be metal.

And you might be courting disaster cause if that riser has a hole in the jacket and you don't know it will fill your cylinder with water.

The impeller missing where did you find it?

To the original poster.

Take off the valve cover, spray with oil?

For a 4 month layup?

Is it me, don't do that.

The riser and manifold has to be addressed.

That closed cooling system in my humble opinion causes more problems than it cures.

And heat exchangers you can keep them.

Power steering also.

That whole system has to be gone over, Nice project for the winter.

Oh i don't fog ether of my boats.

But thats me, it's up to you if you want to.

Got a 30 year old 3 hp out board don't fog that.

I don't fog my snowblower, 40 years old. Still can throw bricks.