No raw water flow for 380 DA genset

[Blender Boy]

Just found the forum today - glad to see Phoenix rising from the ashes!

I have a 2003 380 DA with a Kohler 5W gas generator. Recently it shut off due to no raw water flow. I know it is either a blocked strainer, bad impeller, or failed pump. Now here comes the whining part: access to the genset is, shall we say, a little tight. Is there a trick to getting easy access to it, or do I just need to lose 50 pounds?

 

[STIHLBOLTS]

Welcome to the board. Two things, fill in your signature with your boat information and add some pictures to the virtual marina.

Second hire a midget, we used to have a midget rental program available but only to those that knew the secret sea ray handshake and no one could remember the hand shake so we give up that idea. :lol:

 

[estebanj]

Not familiar with the boat, but even before getting to the genset, look at the water pick up (underneath boat) and the strainer for any signs of blockage (assuming the strainer is easier to access than the genset).

Esteban

 

[Alex D]

Just found the forum today - glad to see Phoenix rising from the ashes!

I have a 2003 380 DA with a Kohler 5W gas generator. Recently it shut off due to no raw water flow. I know it is either a blocked strainer, bad impeller, or failed pump. Now here comes the whining part: access to the genset is, shall we say, a little tight. Is there a trick to getting easy access to it, or do I just need to lose 50 pounds?

A 380 with a 5KW?? that's strange .. don't they have a 7.5KW gensets??

 

[aquadancer]

I'm surprised about genny access. You should be able to reach the raw water pump / impeller pretty easily. Check the abvious - strainer basket and water flow out of the strainer top with seacock open. If your basket is clean, but you have no flow at strainer top with open seacock, you have clogged intake hose.

Happens to us fairly often - eel grass clogs the intake hose before it gets to the strainer basket. Backflush with garden hose and check for water flow. If your safety swith shot down the genny in time, your impeller is probably fine.

 

[Asureyez]

Clogged Through hull

My bane for Genny's are plastic shopping bags. If ther is one floating on the eastern seaboard my genny will suck it up. They never make it to the strainer but will compact very nicely at the seacock.

With the seacock open crack the strainer lid and if you have a strong water flow, that is not your problem. Try back flushing with shore side water.

If unsuccessful and you stuill have have a very no/slow water flow, then its time for a swim. Go with long nose pliers, a wire coat hanger and a good air supply. Snag the blocking stuff from the water side. At next haul out install a slotted intake strainer on the Genny.

 

[c27win]

re: generator raw water pump

Replacing the pump or impeller is pretty basic. Only problem is having to remove floor panel and lay on your stomach. To make life easier, remove the 2 batteries if you have fat fingers that can't do back flips. Remove both raw water lines, remove both cover bolts and remove impeller. Inspect impeller for missing pieces; remove lines before and after cooler and at strainer. Back flush each line with a hose. Start out with low pressure and cup hand over each line as water flushes each line. Reason is to find all broken pieces of impeller. Once collected all pieces, run sufficient amount of water through each line. (water is cheap). Put all lines back on. Install new impeller (proper direction is a must)

Use slight amount of grease on impeller. Put impeller on shaft. Twist housing over impeller (again, proper direction) remove housing from shaft and impeller will stay in housing. With housing off, check impeller installation. If it looks good, put back on shaft and reinstall the removal process as above.

On Kohler models with a few years of age, check your raw water pump body housing. Is it plastic or metal? If plastic, I would suggest buying updated pump with brass / metal housing. ($200.00) Plastic housings will eat up a new impeller if wore. Metal ones last a lifetime after annual impeller replacing.

Now here’s the hard part........ After replacing raw water pump or impeller and you fire gen set up. If it overheats / shuts down again with GOOD RAW WATER FLOW out of the boat. You have air in your antifreeze / water side of engine. When raw water pump goes bad and it causes gen set to automatically shut down. You have created air in your coolant side of the manifold. Once it gets hot it pushes small amount of coolant into overflow bottle causing loss of coolant and air in the system. What happens is the gen sets circulating water pump (i feel is a sh_ty design) will not circulate your coolant. You must get air pocket out before it works correctly. It can kick your azz!!

Best trick is to........ (Again, make sure raw water is flowing good) On back side of manifold there is a 1/4" pipe plug, remove it. Remove radiator cap and stick a garden hose into manifold (1/4 to 1/2 pressure) filling system until you see a smooth flow of coolant coming out of 1/4" plug hole. Put plug in while water is flowing out of hole. Try not to lose too much coolant as this dilutes antifreeze. For some reason, this process never works on the first time!!!! Be patient because it may take 3-6 times. Start it up, if it shuts down, start process over but take caution of hot coolant. Cool down manifold with hose to a hand touch. Repeat process. Watch 1/4" plug hole carefully; when you see system burp the smallest amount of air out of system, you will know you got it!!!! Very temperamental!!

Once gen set is running with out shutting off, once cooled down you can suck coolant out of manifold (radiator cap) and add antifreeze for correct 50/50 dilution. By removing and adding more antifreeze from manifold, you will NOT have to re-bleed system.

If you in fact ruined the impeller. This is a great time to remove cooler and flush, check for restrictions / flow through cooler. If any of the following, use Meuratic Acid as a great cleaning tool. Do not leave it in the cooler for more than 3-5 minutes. Rinse out. Blow into each end to check for air restriction. Check brass tubes for cleanliness.

Note: When removing air from system and restarting. Put a small amount of water on top of manifold and watch it while unit is running. If it starts to boil or dry real fast, shut unit off and re-bleed system again. Once coolant is circulating correctly, water will dissipate at a slow rate, no bubbling like a cooking egg!!
Just saves excessive temps on the unit!

Hope this helps!!

Frank

 

[First Born]

Re: re: generator raw water pump

Replacing the pump or impeller is pretty basic. Only problem is having to remove floor panel and lay on your stomach. To make life easier, remove the 2 batteries if you have fat fingers that can't do back flips. Remove both raw water lines, remove both cover bolts and remove impeller. Inspect impeller for missing pieces; remove lines before and after cooler and at strainer. Back flush each line with a hose. Start out with low pressure and cup hand over each line as water flushes each line. Reason is to find all broken pieces of impeller. Once collected all pieces, run sufficient amount of water through each line. (water is cheap). Put all lines back on. Install new impeller (proper direction is a must)

Use slight amount of grease on impeller. Put impeller on shaft. Twist housing over impeller (again, proper direction) remove housing from shaft and impeller will stay in housing. With housing off, check impeller installation. If it looks good, put back on shaft and reinstall the removal process as above.

On Kohler models with a few years of age, check your raw water pump body housing. Is it plastic or metal? If plastic, I would suggest buying updated pump with brass / metal housing. ($200.00) Plastic housings will eat up a new impeller if wore. Metal ones last a lifetime after annual impeller replacing.

Now here’s the hard part........ After replacing raw water pump or impeller and you fire gen set up. If it overheats / shuts down again with GOOD RAW WATER FLOW out of the boat. You have air in your antifreeze / water side of engine. When raw water pump goes bad and it causes gen set to automatically shut down. You have created air in your coolant side of the manifold. Once it gets hot it pushes small amount of coolant into overflow bottle causing loss of coolant and air in the system. What happens is the gen sets circulating water pump (i feel is a sh_ty design) will not circulate your coolant. You must get air pocket out before it works correctly. It can kick your azz!!

Best trick is to........ (Again, make sure raw water is flowing good) On back side of manifold there is a 1/4" pipe plug, remove it. Remove radiator cap and stick a garden hose into manifold (1/4 to 1/2 pressure) filling system until you see a smooth flow of coolant coming out of 1/4" plug hole. Put plug in while water is flowing out of hole. Try not to lose too much coolant as this dilutes antifreeze. For some reason, this process never works on the first time!!!! Be patient because it may take 3-6 times. Start it up, if it shuts down, start process over but take caution of hot coolant. Cool down manifold with hose to a hand touch. Repeat process. Watch 1/4" plug hole carefully; when you see system burp the smallest amount of air out of system, you will know you got it!!!! Very temperamental!!

Once gen set is running with out shutting off, once cooled down you can suck coolant out of manifold (radiator cap) and add antifreeze for correct 50/50 dilution. By removing and adding more antifreeze from manifold, you will NOT have to re-bleed system.

If you in fact ruined the impeller. This is a great time to remove cooler and flush, check for restrictions / flow through cooler. If any of the following, use Meuratic Acid as a great cleaning tool. Do not leave it in the cooler for more than 3-5 minutes. Rinse out. Blow into each end to check for air restriction. Check brass tubes for cleanliness.

Note: When removing air from system and restarting. Put a small amount of water on top of manifold and watch it while unit is running. If it starts to boil or dry real fast, shut unit off and re-bleed system again. Once coolant is circulating correctly, water will dissipate at a slow rate, no bubbling like a cooking egg!!
Just saves excessive temps on the unit!

Hope this helps!!

Frank

Wow that is one elaborate first post....you should introduce yourself in the who's who section Frank... :smt043

 

[c27win]

Wesley,

Just try'n to help. Been there ~ Done that!

I barely get enough time on here to review others problems but usually don't have time to suggest ideas. Everyone always has their way, I'm just try'n to suggest mine. Especially when the manufactures should be on here posting information such as this topic.

Example: Servicing Bravo drives.... Tell us or put a foot note in the manual about why to fill the drive from the drain hole instead of the vent hole instead of us learning by our mistakes and costing us the $$$'s for screwing up!

Most of the time it's comman since but there's always the "scratch your head till it bleeds" problem!

Hell, I can't even get my aviator picture to work on here!! LMAO!!

Anyways, thanks and good to read different ideas and posts on here!

Frank

 

[ImpulseIII]

Too many Franks.....C27win will have to change his name..... :smt043 Welcome "new" Frank

 

[Bounty]

Just found the forum today - glad to see Phoenix rising from the ashes!

I have a 2003 380 DA with a Kohler 5W gas generator. Recently it shut off due to no raw water flow. I know it is either a blocked strainer, bad impeller, or failed pump. Now here comes the whining part: access to the genset is, shall we say, a little tight. Is there a trick to getting easy access to it, or do I just need to lose 50 pounds?

A 380 with a 5KW?? that's strange .. don't they have a 7.5KW gensets??

5 KW is more than enough unless you have A/C.

 

[J Levine]

I would be carefull about changing to a slotted thru hull strainer on a generator. I know the owners manual for my Westerbeke cautions agains doing this as the slotted scoops of the the strainer can push water into the engine through the exhaust.

 

[Asureyez]

Install them right

Slotted intakes should not be installed with the slots facing forward. No thru hull intake should function as a ram scoop.

Slotted thru hulls are installed with the slots toward the stern.

 

[Bounty]

I would be carefull about changing to a slotted thru hull strainer on a generator. I know the owners manual for my Westerbeke cautions agains doing this as the slotted scoops of the the strainer can push water into the engine through the exhaust.

Exactly right.

 

[J Levine]

Does anyone have a suggestion on what can be done to the straight thru hull on the generator to keep crap from coming in? I run my generator at all times when I am cruising and as a result here on the Barnegat Bay I need to clean the strainer every weekend because the eel grass fills it up quickly.

 

[ImpulseIII]

Jon, There is a strainer cover that is made especially for eel grass. I was thinking about getting them once upon a time but never got around to it. I seem to recall that Roy over at Good Luck Point had them but I am not 100% sure and my quest was about 5 years ago. Give him a call and ask....

 

[J Levine]

Hi Frank

Hope life in PA/MD is treating you well. I am familliar with the strainer covers that folks use for the mains but I hesitate to do anything to the generator for fear of flooding it under power. All I can envision is somthing a kin to a shower drain to cover the opening. I really dont have much trouble with the mains, but the generator and the AC strainer they are always filled.

 

[Asureyez]

Just a thought

You can't keep from picking up the debris, but you can give it more space.

Consider installing a larger dia. thru hull and a larger capacity sea strainer.

To make the job easier is there any opportunity to relo the strainer to give better access?

 

[ImpulseIII]

Hi Jon,

Life in PA//MD is great but then again, if you manage to escape Joisey (sorry Dominic) anywhere is great!! Seriously, we are really enjoying the Chesapeake and you should try to make next years BIH get together! (you and Dominic can discuss that over cigars at the "secret spot")!!
Oopps...sorry Wesley..I'm hijacking the thread..... :smt018

Back to strainer covers. I don't recall hearing anyone having problems with gensets of A/C using the eel grass strainer covers.

Oh well.......good luck, whatever you do.

 

[Alex D]

Just found the forum today - glad to see Phoenix rising from the ashes!

I have a 2003 380 DA with a Kohler 5W gas generator. Recently it shut off due to no raw water flow. I know it is either a blocked strainer, bad impeller, or failed pump. Now here comes the whining part: access to the genset is, shall we say, a little tight. Is there a trick to getting easy access to it, or do I just need to lose 50 pounds?

A 380 with a 5KW?? that's strange .. don't they have a 7.5KW gensets??

5 KW is more than enough unless you have A/C.

That's probably true, but I have never seen a 380 without air, not have I seen one with a genny smaller than 7.0kW