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97205LT1
06-28-2009, 09:37 PM
Need some technical advice on a 97’ Prostar 205 with an LT1. Purchased an Indmar Manual but it does not include the LT1. There’s a steady stream of water dropping down onto the crank pulley/belt when engine is running. Believe it is coming out the bottom of the water circulation pump. It is not coming from the raw water pump attached to the crank pulley. Assumption is the water pump has the two large hoses closest to the top of the engine (how is this driven appears to be no belts to it?). . Here are some questions.

1. Is there a gasket or hose between the block and water pump toward the bottom causing the water leak or is it the pump.
2. What are the steps to remove the pump
3. Lastly is this the same pump as a corvette engine and maybe can be purchased at auto parts store to save $$

Thanks

babymoore3
06-28-2009, 09:48 PM
Generally there is a weep hole indicating a seal has gone bad in the circulating pump which causes this. I am concerned with your statement, "how is this driven?" Are you overheating at all? Most engine circulating pumps are driven via belt from the crank pulley... Check some of the engine links and I am sure TMC#1 has an engine pic on here....

97205LT1
06-28-2009, 10:00 PM
The engine is not everheating. Attached is a pic of the water pump. really don't know how it is driven...

babymoore3
06-28-2009, 10:18 PM
TMCNo1's engine (I knew there was a picture, had to find it). The belt normally drives from the crank to the water pump to the alternator and back to the crank pulley. If you are not V-belt then you are serpentine (5 ribs) driven and you may also have tensioner or idler.

http://www.mastercraft.com/teamtalk/album.php?albumid=4&pictureid=29

97205LT1
06-28-2009, 10:38 PM
I believe that is a throttle body or carburated engine. Mine is a LT1 and does not have the pulley on the water pump as in the picture....

babymoore3
06-28-2009, 10:56 PM
Grab a pic when you can I'd be interested, check underneath to see if the water is coming from a weep hole (probably about 1/8"-1/4" hole) - some engines are gear driven but not too common on this size engine. Maybe someone with an LT1 will respond with exact info... did you search for similar boats /engines and look at user pics?

My guess is you lost a seal internal on the circ. pump (why the weep hole is there), gaskets don't usually go unless you have loose or broken bolts.

In you diagram, you have a triangular shaped item with four hoses (thermostat region) and the large hose on the left. This hose should feed the circ pump (1). That is where you are leaking down onto the crank pulley, correct?

97205LT1
06-29-2009, 08:25 AM
The water is leaking above the triangler area inward/toward the engine. Its hard to see where the water is coming from.

Thanks Tom

bigmac
06-29-2009, 08:37 AM
Generally speaking, leaking from a circulating pump means it needs to be replaced. I think that's where you're headed.

97205LT1
06-29-2009, 08:47 AM
Aggree it most likely is the pump. Trying to find out if there are any tips replacing the pump.

Thanks

JimN
06-29-2009, 09:21 AM
Aggree it most likely is the pump. Trying to find out if there are any tips replacing the pump.

Thanks

The first thing- don't use a circulating pump from anything other than the LT-1. If you look at the front of the motor, it should be pretty self-explanatory.

97205LT1
06-29-2009, 09:33 AM
Is the pump gear driven and is there a difference marine application to auto. Would be easier and less expensive at the local auto parts store.

Thanks

Andyg
06-29-2009, 10:43 AM
The pump is shaft driven from a shaft that is driven off the timing chain. There is no difference between an "auto" version LT-1 circulating pump and a "marine" version. As long as you get an LT-1 circulating pump it will work properly.

97205LT1
06-29-2009, 08:22 PM
Pulled the pump and the bearings were falling out. Tried the local outo parts store on an LT1appears to be four part numbers. Does anyone know if the water pump goes directly into the cam gear or is there a sleeve between the water pump and cam gear. Where wondering if the sleeve is corroded on the pump side on mine. The water pumps at the parts store don't extend fair enough to the cam gear.

Thanks

trickskier
06-29-2009, 08:58 PM
Give Chuck a call at BAWS 813-996-2297 he'll be able to help you. Tell him Trick says hi!!! :D

babymoore3
06-29-2009, 09:33 PM
Wish I could help more but now you are engine specific and I am working with a ol' 351 carbed. Sure would be nice to have an LT1! Good luck and I am sure you'll find the help you need!

Andyg
06-29-2009, 10:42 PM
Pulled the pump and the bearings were falling out. Tried the local outo parts store on an LT1appears to be four part numbers. Does anyone know if the water pump goes directly into the cam gear or is there a sleeve between the water pump and cam gear. Where wondering if the sleeve is corroded on the pump side on mine. The water pumps at the parts store don't extend fair enough to the cam gear.

Thanks

I pulled the water pump on my 97 PS190 several years ago to replace the oil seal for the shaft that drives the water pump. If memory serves me correctly, that was several Captain and Cokes ago there is a splined sleeve that connects the shaft of the water pump to the pump drive shaft that comes out of the timing cover. I have attached a schematic that shows what I am pretty sure was the way my LT-1 was assembled. I don't know if the part numbers that are listed are accurate.

billr
06-30-2009, 08:22 AM
Replaced mine two years ago, purchased from the Chevy dealer. There is one extra hose connection that will need to be blocked off, and it comes with an automotive 180 degree t-stat. It also needs to be painted.

97205LT1
06-30-2009, 11:14 AM
Andyg, Thanks much for the pic!

Billr, Doesn’t the top thermostat need to be the 160 degree with a drilled hole and what do you mean the thermostat needs to be painted.

Thanks

TMCNo1
06-30-2009, 11:26 AM
Andyg, Thanks much for the pic!

Billr, Doesn’t the top thermostat need to be the 160 degree with a drilled hole and what do you mean the thermostat needs to be painted.

Thanks

The water pump needs to be painted black.

billr
06-30-2009, 03:30 PM
#1 is correct. I was just making you aware the pump comes with a 180 degree automotive t-stat. Yes it needs to be changed.

blackcreek
07-01-2009, 06:44 AM
Did you get a new water pump? I just replaced mine, all LT1 part numbers will work on a boat. The only difference is the heater hose pipes coming out of the pump. The cheapest option is a NAPA rebuilt pump for a 96 Buick roadmaster for 56 bucks then cut the heater pipes short and use a cap and hose clamp on the ends. I actually pulled the hoses out of the pump and had a 1/2 inch and a 3/8 inch pipe plug tapped in the open holes for 15 bucks at a cylinder head shop. My pump was leaking at the rear drive seal and one of the unused heater hose outlets. Vette, Roadmaster,Camaro/firebird, and Caddy LT1 engines from around 93to 96 or 97 should work. You can't mistake the LT1 pump for anything else as it has the pump drive from the cam.
I also found a Carter fuel pump number for for 150 bucks that looks like it will work. The pump looks identical but I have not replaced it yet to check for exact same fuel pressures. NAPA guy said the pump will work, I will post up the number when I get around to putting the fuel pump in and make sure the pressures match.

97205LT1
07-02-2009, 11:35 AM
Traditional Auto Parts Store tracked down the pump (Parts Master #58-445) for $116. Only needed to paint it.

Blackcreek, Thanks if I knew this earlier would have saved a few more bucks.

All thanks for the assitance along the way, forum is very useful.