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Raw water pump

J

jclays

Regular Contributor
After removing the impeller of

After removing the impeller of my raw water pump I found numerous screw driver dig marks on the inside casing as well as hammer marks and some deformities on the shaft itself. I purchased a new Sherwood E35 pump rather than rebuild the old one for peace of mind..Now the problem.. The hub where the pulley bolts on is larger in dia. as well as in thickness. I found a new pulley at the marine shop that fit. When I mounted the pump the pulleys where out of alignment aprox 3/16 of an inch off over a short run. You could see the belt angle off the top of the pulley. I cannot get any fore and aft adjustment only side to side. The pump is a pedestal style mount and mount is slotted for only side to side play. I pressed the hubs off the new pump and the old pump to swap however the hub on the old pump pressed on to the new pump shaft with very little pressure vs the amount of pressure to remove the hub that came with it. Im afraid that with the torque of the engine the hub will spin or spin off. The new hub is twice the thickness of the old pump hub. Im thinking of taking the new hub to the machine shop and having them take off 1/8th of an inch from both sides of the hub or all 1/4 inch off of one side and have the hub pressed deeper on the shaft. Anyone else have this situation??? Both pumps are the same Sherwoods however the old pump is circa 1966 hub changed in 43years. Cast iron pully to modern stamped steel.
 
"James:

does that last sent

"James:

does that last sentence represent your thought? It may be easier to get a 'new' pulley to get the belt back into the correct plane.

Make sure the hub is pressed back on to have the shaft portrude the correct amount (0.13"). This lets the pulley center over the shaft. If not done, it could produce what you described (pump pulley too far forward).

You could always call Sherwood's tech line @ 1-800-445-8360 to see if they changed anything."
 
I had a machine shop remove 3/

I had a machine shop remove 3/16 of an inch from the backside of the hub and was able to seat the hub that much deeper onto the shaft and still not hit the bearing or clip. The new pulley sits 3/16 deeper which will allow the belt to line up. Mako I did get a new pulley thats how we ended up 3/16 too far forward. The new hub was substansially larger/thicker than the original hub thus pushing the new pulley out. The new pulley had a portion of the shaft pertruding thru it. It now will have 3/16 of the shaft exposed. I'll mount it today and see the alighnment.
 
Mounted the pump. Its now stra

Mounted the pump. Its now straight. will plumb the hoses and add the missing thermostat and pressure relief valve on to one engine for now and run it to see why they where removed from both engines.I'll leave the starboard engine as is without the thermostats since I know how it will run while I test the port engine.
 
Don't forget to put that t

Don't forget to put that t-stat back in. It's a critical item on marine engines to prevent sludge.

Jeff
 
All back together. Also instal

All back together. Also installed the thermostat and pressure relief valve on one engine to test why they were missing on both engines. Idled at the dock for 45 min good water flow out the exhaust from the new pump. No change in Temp with the thermostat and pressure relief valve installed. 120 degrees after 45 min idle. will have to sea trial when i have more time.
 
"Too cold. Something is still

"Too cold. Something is still wrong there. At least it's not the other way around! Much easier to make her warmer.

Could you install an in-line t-stat like race cars use? They make a housing that goes in the hose, with a separate hose back to the inlet side of the pump.

Jeff"
 
"James shouldn't have to J

"James shouldn't have to Jeff,
i don't think that even Nas-Car used the in-line t-stat back in the era of his boat '66.

Whats the "pressure relief valve" that James is talking about?

Fred 156-M"
 
"James:

did you check the t

"James:

did you check the thermostat before your installed it? I'm curious about the pressure relief valve, too - what and where in the system."
 
NASCAR uses tape on the grille

NASCAR uses tape on the grille to elevate the water temperatures (for some totally dumb reason).

Jeff
 
"Water pressure relief valve.

"Water pressure relief valve. THat would be a RWC item, in which case, the 120 deg engine temp at dockside (neutral) seems pretty normal. Should go another 20 deg up with cruise load."
 
Didnt check the thermostat exc

Didnt check the thermostat except for manually checking that it moved. The pressure relief valve sits in the same housing as the thermostat and above the 2 hoses that feed into the exhaust. Not sure of their purpose. If you look at the schematic of the old style Crusader thermostat housing it is a large blockie thing with 2 orfices. One for the thermostat and one for a pressure relief valve. The water hoses attach here.
 
"<[img]"http://www.marineengin

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pressure relief
 
"[i]NASCAR uses tape on the gr

"NASCAR uses tape on the grille to elevate the water temperatures (for some totally dumb reason)

They don't actually use the tape to control the temp., they use the tape to add downforce, but remove it when they find it too restrictive of cooling air passages.

Had to chime in with that tidbit. My head is filled with useless information."
 
"Rick..I am accused of this ev

"Rick..I am accused of this every day...useless information ! Here's one for ya...When a log is burned in a fireplace, it gives off heat calculated in BTU's. Should the same log rot away over 30 years or so in the woods...it gives off the same amount of heat or BTU's.
The main center supports of the Verrazano Narrows Bridge are placed 5" wider apart on top to allow for the curvature of the earth...

it sucks being so brilliant !
wink.gif
"
 
"The diagram that diver dave s

"The diagram that diver dave shows for the big block is the same for the small block. parts #2,3,4 are the components for the pressure relief valve. Not sure of its function. I am 100% raw water cooled."
 
"james: did you put in a new t

"james: did you put in a new t-stat or reuse the one you had? I'm thinking a new one is worth the effort

diver dave: thanks for the diagram - surely worth many, many words.

Al: The log story is flawed. The log has a heat content for when it is burned. If it isn't used as fuel, those BTUs are never liberated. Same for gasoline; if it decomposes, its btus aren't consumed....."
 
"I was told that an engine wil

"I was told that an engine will only put out a limited amount of heat energy,,, how fast do you want to use it up?

Fred 156-M"
 
"If that relief valve is stuck

"If that relief valve is stuck open, the motor won't warm up.

Jeff

PS: For qualifyong, NASCAR guys want the motor to run hot (for some reason) so they tape the grille for that reason as well. Every car has a gen-set on wheels beside it while in the qualifying line, powering a heater in the oil tank,"
 
T-stat and pressure releive va

T-stat and pressure releive valves are brand new. The engines where running with out them for years prior to me buying the boat 3 years ago. I have just put them in one engine since I was working on it. I want to see why they didnt have them installed. If all goes well I will install them in the starbord engine also.
 
"If you've obtained the on

"If you've obtained the one for the starboard engine, you may want to check its operating point in a pan on the stove.

When you run the port engine, does the temp gauge show the classic 'peak' when the t-stat opens? You may want to check the housing at the same time with the IR gun.

You may also check at the supply house to find out which brand they sold you. Some of the overseas stuff has been known to have a wider band of "acceptable performance", for a variety of reasons."
 
Gauge doesnt show anything.. T

Gauge doesnt show anything.. The needle doesnt come off 120degrees while idling at the dock in nuetral. I'll take the boat out this weekend and see if the gauge climbs. The boat is 100% raw water cooled and has never run warmer than 120 degrees.
 
"that sounds like a good next

"that sounds like a good next step.

you may also want to check the gauge and the sender wiring using the "resistor" method. you used to be able to buy them at any radio shack though I haven't checked recently. a 240 ohm resistor, between the sender wire and a good ground, should show ~ 100 deg on the gauge, a 33 ohm resistor should show ~ 240 deg, and a 110 ohmm resistor should put the needle at half scale."
 
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