1973 Gibson help

[Bdunbar44]

Hey guys I’m new to the thread and need some help. I have a 36’ Gibson houseboat that has a Nissan/chrysler 6cyl diesel in it. It has been sitting for a few years and I got it fired up after a little TLC. My question is does this engine have an impeller? It has antifreeze in it and I can see it circulating but I took it out for the first time yesterday and the temp went to 230 deg. No higher just 230! I went back to the dock because I didn’t know if that was hot or normal. When I got back in I let it run until I got docked and the temp fell to 180. If it has an impeller I’m sure it’s garbage after me turning the engine for two days trying to get the injector pump cleaned and bled out. Where would I find the right impeller and where is it?

 

[alldodge]

Welcome
All boats have some sort raw water pump that moves water either thru the motor or thru the heat exchanger. Most likely yours has a belt or crankshaft driven water pump.

In other forums I'm finding the Sherwood G7B pump used
https://www.amazon.com/G7B-Engine-Cooling-Pump-Outlet/dp/B004HK97U8

 

[Bdunbar44]

So you feel like it has a pump not an impeller?

 

[Scott Danforth]

So you feel like it has a pump not an impeller?

it will have a raw water pump with a rubber impeller in it.

 

[Bdunbar44]

I read somewhere it has a duel cooling system. When I take the cap off I see antifreeze circulating. Is the a valve somewhere to switch it from raw water to the radiator or is it a duel deal that works together?

 

[Bondo]

I read somewhere it has a duel cooling system. When I take the cap off I see antifreeze circulating. Is the a valve somewhere to switch it from raw water to the radiator or is it a duel deal that works together?

Ayuh,..... Welcome Aboard,..... There should be a heat exchanger where the antifreeze is cooled by the raw water from outside the boat,.....

 

[Scott Danforth]

the motor and heat exchanger will have antifreeze, the raw water loop is the inlet strainer, the raw water pump, the raw water side of the heat exchanger, and then it discharges into exhaust

 

[Bdunbar44]

Glad I joined the site! Hahaha ok so when I took it out the other day it went up to 230 degrees. Could that have been because the lake water was 80 degrees or maybe a thermostat? I feel like if the water pump wasn’t working it would have gotten hotter than that. I drove it about a mile at 3000 rpm’s and it never went over 230 degrees.

 

[alldodge]

If that was a gas motor you would have blown a head gasket. That temp can also damage the diesel . Temps should not go above the thermostat setting, no more than 180

Replace the impeller

 

[Bdunbar44]

Ok the next question is… where in the heck am I gonna find an impeller? I can’t find parts anywhere.

 

[alldodge]

First find out what model pump you have, then it should be easy enough to find parts or replacement.

 

[Bdunbar44]

I have no idea what pump. It’s a CN6-33 crysler/Nissan straight 6 diesel engine

 

[alldodge]

The motor is not used on just Gibson houseboats. The pump may also have been replaced by another, so we also don't know. Unless there is some kind of serial number that can be looked up somewhere showing a parts brake down we have no where to look.

Look at the motor and find the pump. The pump will have 2 large hoses connected to it. See if you can find anything on it which someone might be able to figure out which one you have

 

[Bondo]

I have no idea what pump. It’s a CN6-33 crysler/Nissan straight 6 diesel engine

Ayuh,..... Which is not a standard well known motor, which we can't see,.....

 

[alldodge]

Look at thread below, and in post 4 there are some pics and the pump has been removed and laying in front

https://www.marineengine.com/boat-f...iesel-sd33-and-patrol-160-series-sd33.421902/

 

[Bdunbar44]

When I get off work I will go take some pics and hopefully get this figured out. Thanks

 

[Bdunbar44]

 

[Bdunbar44]

 

[Bdunbar44]

Ok guys that’s what is on the Engine.

 

[Bdunbar44]

I guess the question is… is there a replaceable impeller in the brass housing or do I buy that whole assembly?