1955 CC Hurricane Restoration

Alan you are the man. Even though I saw it pull away from the dock I can't wait to see videos of her under a load.

Mark, good to see you again last weekend and glad you made it home safely. here's what I've found so far, after discussing this with Dave Van Ness who rebuilt the water pump we're pretty sure we've got it figured out.

It is simply a bad thermostat. Inside that thermostat housing there is of course a stat and a pressure relief valve. With the raw water pump functioning correctly there is sufficient water pressure in the loop to bypass a small amount of it to the exhaust elbows to keep them cool while the engine is warming up.    The stat in this motor is normally open. In the open (cold)state, water is redirected back down to the raw water pickup and recirculated back into the engine. This recirculation occurs until the engine gets up to 135 degrees, the stat closes and allows hot water to exit via the exhaust elbows. The stat will regulate how much water exits opening and closing the recirc loop to keep the engine temp constant.

With the stat frozen open the hot water never exits the motor and is only being recirculated back into the engine so the temps continue to climb. The pressure relief valve has 4 small openings that allow just enough water to exit to the exhaust elbows to keep them from over heating that's why I was getting a fairly normal temp reading on them with the gun even though the system was not functioning properly.

A quick fix for last weekend would have been to simply take a pair of vise grips and clamp off that recirc line, that would have forced the hot water to exit the motor via the pressure relief valve. The result would have been like running with no stat at all and we may have run cold but better than the situation we had.

Van Ness has rebuilt several of these Hemis and says there really is no issue with the pump sucking air from that return line because that stat when operating properly closes that recirc line off. Biggest problem I have now is finding a new stat, they don't exist. van Ness has a few old ones he is testing to see if they still function and I should find out today, worst case scenario is I install a shut off valve on the return line and force the motor to run a little cold until we get the proper stat in it.

I'll post a photo of the thermostat later, it's not a typical spring type stat. It is a wax filled coil that will expand when the wax gets heated, mine must be leaking and can't hold pressure.

We're real close now and the boat will hit the water again next weekend down at Lake Clinton and will run this time, I think.

scottb wrote: Can't wait to see it running on the water. Scott

Ha, Me too! Hope you guys had a great week in TN.

8122pbrainard wrote: turningpoint84 wrote: How exactly does this gear setup work? The engine spins these gears(impellers) and the water is pushed by there gears? Seems strange, never heard of using gears to push water. I figure you'd want a more plunger type like most of our boats. Peter, Sorry but once again you have inserted you foot into your rectum since you did no research nor have any knowledge on pump types before posting. Yes, gear pumps are very common especially on older marine engines. Here's the one I did on my 1927 Flexifour. You could also have done a site search and found Older threads like "no super sucker needed" I thought you were an engineer???????

D in fluid mechanics. :)

But honestly I just had to refresh my memory, sorry for getting your blood boiling again old man.

When geared up, almost anything can pump

8122pbrainard wrote: turningpoint84 wrote: How exactly does this gear setup work? The engine spins these gears(impellers) and the water is pushed by there gears? Seems strange, never heard of using gears to push water. I figure you'd want a more plunger type like most of our boats. Peter, Sorry but once again you have inserted you foot into your rectum since you did no research nor have any knowledge on pump types before posting. Yes, gear pumps are very common especially on older marine engines. Here's the one I did on my 1927 Flexifour. You could also have done a site search and found Older threads like "no super sucker needed" I thought you were an engineer???????

That looks like an oil pump from a Harley Evo motor Pete. Only bigger

Mike

turningpoint84 wrote: C-Bass wrote: Gear style pumps are very common. Not sure how common in marine systems, but in general. Makes sense, i guess i should have said it doesn't seem like it would be very efficient, but I'm wrong on a lot of things.

don't forget this is 1955 technology, probably state of the art at one time. Seems like everything current uses flexible impellers for this applications.

I looked into retrofitting with a more modern pump, it could certainly be done but since the old pump is serviceable we'll repair it.

Gear style pumps are very common. Not sure how common in marine systems, but in general.

81nautique wrote: There you go, it pumped two years ago when I fired it but no telling how old these gears are. At least we know what we've got to deal with now.

Alan....looks much the same as mine, may be good to flush out the engine with the pump off as it looks like something gone through the pump......my guess is its lumps of rust from inside the engine as you bring her back to life, that drop down each time you shut off the engine.
May take a few heat cycles to clear her out I would order a spare set or two.

PLBC wrote: Alan, I like Joe am too lazy to look back, when you first fired the engine was it on a hose or pulling from a bucket? BTW, looks awesome wet, cannot wait to see it. You must be quite proud, and you should.

On a hose, should have checked it then but it wouldn't be any fun if I only had to do this stuff once.

ok. that makes sense.

Wow, very interesting cooling loop. Why the exhaust manifolds first? Or is there no real explanation.

Have you found new impellers Alan or are they a hard find? Look to be the same type as Rogers.

There you go, it pumped two years ago when I fired it but no telling how old these gears are. At least we know what we've got to deal with now.