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High Volume sea pump options
I would like to replace the stock belt driven bravo sea pump (plastic) with something that will move more volume. First off, does anyone know the gpm of the stock merc pump? Second, is there a standard belt driven replacement pump that will move more water and what capacity would it have? Lastly, could the stock merc pump take the higher rpm of changing drive pulley to a smaller pitch? I run closed cooling so excessive water pressure is not a concern.
BT |
Re: High Volume sea pump options
Try a thru transom water pickup. I know it will give you more volume.
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Re: High Volume sea pump options
Hey, thats a good idea :eureka: I do run out of a tidal, low water marina though. Could be an issue with sucking up mud. I ponder that, thanks.
BT |
Re: High Volume sea pump options
West Marine carries a all bronze body replacement pump that can be mounted with either the Merc hi-performance mount or the stock three bolt mount. I have used them on 540 CU IN blower motors and 598 CU IN N/A engines with good results. You can also use the Eickert or Hardin dual impeller pump for more flow, but the water passage in the Bravo is to small, so you need a sea strainer and external water pick up.
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Re: High Volume sea pump options
You know, the stock pumps push a lot of water through. They will cool 800 HP with no problem. You may want to try the transom pickups and see how that works. Are you actually having a problem with temps?
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Re: High Volume sea pump options
the stock pumps with the right size hose attached and no restrictions will pump huge amounts of water. I work for March pumps here in IL. The dept i manage makes the pumps for the Marine Air A/C systems that just about any boat with A/C has. We did a test of the merc sea-water pump here on the test tank we have in house. We were looking into possibly making a rubber vein impellor type pump in our product line. We hooked the Merc pump up straight shaft through a collar to a 3hp elec motor. One of the first tests we did was to see how much power it would take to trun this pump over.....The 3hp couldnt do by itself without some help getting the pump turning....unfortunatly we didnt have any of our bigger pump motors avail at that time. Anyway at 3000rpm this pump is capable of pushing over 100' of head height!!! I dont recall what the GPM's were cause we did this test about 2 yrs ago but i can say that cooling should not be any problem as long as you have a good water supply and a good impellor in it. :)
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Re: High Volume sea pump options
Not having a problem insptech, just wanting to move more water throught my exhaust and possibly improve oil temps. Right now I have to run engines with no tstat in coolant to keep oil temps in check. I believe more flow would help. not looking for pressure, just flow.
Thanks for the ideas BT |
Re: High Volume sea pump options
If you are having oil temp issues then you need to upsize the oil coolers. That should take care of the problem.
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Re: High Volume sea pump options
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I bought a replacement housing / impellar from KTM. It comes with a 1 yr warranty against impellar failure and pumps more water than the merc. I used it this season and it works very well. It requires some modification of the stock drive. Here is a photo of the unit.
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Re: High Volume sea pump options
I already run large coolers Bigw. 3x16, 3x22 w/ps Eddie Marine. I believe the problem lies in the fact I run closed cooling. The engine heat exchanger causes more restriction than running without. Maybe I should buy heat exchangers with larger tubes... hmmm.
How much was that pump Wette Vette? What needed to be modified to make it work? Did you get a noticable increase in flow out the exhaust? That is what I am after. BT |
Re: High Volume sea pump options
The kit was $250 and the only modifications required were driling holes in the mounting bracket. Pretty easy to retro-fit. I bought the pump because they claimed the impellar was nearly indestructable and they were willing to warranty it for 1yr with no questions asked if the inpellar fails. They claim you can run the motor dry and not hurt the impellar. I didn't notice increased flow, but never really checked. Their claim is the pump moves more water, but I cannot verify. I lost an impellar last season and went with this pump because of its durability claims.
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Re: High Volume sea pump options
How about teeing off the cooling system before the heat exchangers and feeding the oil coolers? Almost like what you would do for a chiller. This may increase water flow to the coolers and bring down temps. My problem is the opposite-my oil temps are too low and I'm installing thermostats to bring them up :cool:
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Re: High Volume sea pump options
I think I will check them out Wette Vette. Do you have a web site? I run KE headers and am looking for more insurance against melt down. Because I run closed cooling, it may not be quickly evident if I lost sea water flow. May install pressure gages too.
Ted, the oil coolers are first in line after the seapump. They get the coldest water. But if the water flow through the cooler is too low due to other restriction upstream, the water will become thermally saturated and my oil will heat up. I'm wanting more flow through the coolers for this reason. The more I yak the more I think the engine heat exchanger may be the constraint. Could be the suction side as well though. Anyone ever install thru hull water pickups before? What are transom pickups? BT |
Re: High Volume sea pump options
Originally Posted by insptech
My problem is the opposite-my oil temps are too low and I'm installing thermostats to bring them up :cool:
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Re: High Volume sea pump options
After chasing hi oil temp for years, I finally figured out that the problem was really the oil pan. Once I got that handled was able to run 3 x 12 @1000 HP, also close cooled. BTW what do you consider hi?
I had pressure gauges at the feed for the headers. Just as you suspect you can have an exhaust melt down before the engine overheats. |
Re: High Volume sea pump options
Blue Thunder,
I went with external pickups and strainers after the stock Bravo style water inlet corroded to about a 1/4 " opening. I have some new Stainless Marine transom mount pickups I'll let ya have cheap. Not sure where you are on the Bay, I may not be that far from ya. I'll be glad to show how my pickups are setup as well. PM me if your interested. |
Re: High Volume sea pump options
I dug out my receipt and the pump is actually KPM, not KTM. The website is "teamKPMracing.com". KTM's are motorcycles!! :p
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Re: High Volume sea pump options
Yeah, I figured the heat exchanger might be reducing flow volume and that's why a T in front of it might give you more flow through the cooler and then just dump them out the side. Transom pickups mount at the deepest part of the V on the transom-best place to pick up water for full flow and nowhere near as much restriction as a drive pickup. I am running crossovers with no thermostats so the temps stay low, just need to bring the oil temps up a little and it will be all good.
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Re: High Volume sea pump options
the drive pickup is a big restriction on the suction side u must go to hull pickups as they will feed the system at speed and just blow thru the merc pump then u trim the pickup to adjust the water pressure as it is easy to have way too much pressure if you insist the large diesels run up to a 4 inch inlet and discharge picture your exaust hose on the inlet to seastrainer! we run a globe impeller in a merc pump(soft so it is easy to bypass)we had to glue and safty wire all the hoses on as the first test we had 140 psi inlet pressure ! all hoses are 1.250 and we bleed off water for the intercooler at the sea strainer that we installed a pressure relieve valve to dump excess overboard(1400)hp
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Re: High Volume sea pump options
Site pages are slow to load , I gave up on a few.I have never heard of these guys??
http://www.team-kpm-racing.com/products/index.html http://www.team-kpm-racing.com/produ...ges/page3.html |
Re: High Volume sea pump options
I haven't heard of them either. I found them on the web searching for alternatives to the impellar failure prone merc pumps. They are pretty knowledgeable and so far the pump has worked great. I figured it was worth a try!!
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Re: High Volume sea pump options
Good to know Fred!!! I got a real good feeling about Dan and these pumps after speaking with him. Heck, a rebuild kit for a stock merc is abound $90.00 if a new ring is needed so spending $250 and getting a 1 yr guarantee seemed reasonable to me. If these can truely be run dry and take the abuse KPM claims it will be money well spent!!
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Re: High Volume sea pump options
Originally Posted by WETTE VETTE
Good to know Fred!!! I got a real good feeling about Dan and these pumps after speaking with him. Heck, a rebuild kit for a stock merc is abound $90.00 if a new ring is needed so spending $250 and getting a 1 yr guarantee seemed reasonable to me. If these can truely be run dry and take the abuse KPM claims it will be money well spent!!
Question??I wonder if you just replace the impeller or does it usually wear the housing also??? Fred Glad to know your picking them up :D http://marineengineparts.com/shopsit...ia/18-3150.jpg |
Re: High Volume sea pump options
Originally Posted by Mbam
After chasing hi oil temp for years, I finally figured out that the problem was really the oil pan. Once I got that handled was able to run 3 x 12 @1000 HP, also close cooled. BTW what do you consider hi?
BT |
Re: High Volume sea pump options
Run a good 10 QT pan from Dooley, Gil, Stefs, or Dan olsen or others and only run 8-9 QTS. This will help keep excess oil from hitting the bottom of the pistons and will keep your oil temps down. The oil coolers you have should be able to keep your temps in check. Are you measuring your temps in the pan or after the oil cooler? 230 in the pan is a nice temp to run if it can be maintained. I measure mine in the pan and 250 is my shut down point and so far I haven't seen them get there. Are your oil coolers before or after your coolant heat exchangers? If they are after your coolant exchangers the pre-heated water could be causing your oil cooling efficiency to be less. Just some ideas i'm sure you've already considered.
Craig |
Re: High Volume sea pump options
I measure the oil temp at the filter pad which is first stop after the oil pump. I'll check out the pans you listed Wette Vette. Those are cool looking water pumps there. What type of pump are they, impellor, centrifugal.... seems like a great price for how they look.
Do you have prices yet Too Old on complete setup... bracket, pump, pulley flange etc? BT |
Re: High Volume sea pump options
BT, What kind of cast pans do you have? Should be possible to modify them. If the clearances are right, and the oil is not getting aerated 280 deg in the pan (using Mobil 1) is really not too scary.
I prefer aluminum over steel. |
Re: High Volume sea pump options
I have the cast aluminum pan that came stock on the 365 mag engines in late 1980s Mbam. Seem to hold 6 qts. What can be done to modify them to improve oil temps?
BT |
Re: High Volume sea pump options
I'll try and take some pictures, I normally start with an Eickert or Mercury pan. You need to find a good friend with a TIG welder and some time, otherwise it coud get pricey.
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Re: High Volume sea pump options
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Dave,I have Johnson crank mounted seawater pumps that pump half what the Merc pumps do. Max w/p is 10 psi yet my water temps rarely go over 150 and I don't think oil temp has ever seen 220...usually around 200. I DO have a 10 qt Canton pan. Total dry (initial) fill was 12 qts.Oil temp is taken off the pan as you can see in the pic.
The larger capacity may have something to do with it. Cal |
Re: High Volume sea pump options
Are you still sucking through the stock drive pickup Cal? I think different high capacity pans are in my future. Anyone have two good used pans to sell? I am going to work my heat exchanger restriction idea some. I think that is a contributor too to a restriction in flow. Maybe do something like Insptech was suggesting... a dump of some sort. Last but not least, I think a set of water pressure transducers and gages are in order. That is my primary objective anyway.... not frying my headers.
BT :cool: |
Re: High Volume sea pump options
Originally Posted by blue thunder
Are you still sucking through the stock drive pickup Cal? Last but not least, I think a set of water pressure transducers and gages are in order. That is my primary objective anyway.... not frying my headers.
BT :cool: Transducers for w/p??? Every w/p guage I ever had was strictly mechanical , like a mini speedometer in psi not mph. |
Re: High Volume sea pump options
Originally Posted by mopower
Yep , thru the Bravos. Ones a 95 with side pickups and the other is an 02 with dual pickups and that's more trouble than it's worth :(
Transducers for w/p??? Every w/p guage I ever had was strictly mechanical , like a mini speedometer in psi not mph. |
Re: High Volume sea pump options
i just bought a pair of 2 stage K.E. water pumps from tyler crocket for 675.00 each cheapest i could find them anywhere. tyker was great to deal with. ratman
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Re: High Volume sea pump options
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Originally Posted by offthefront
cal .. so you run water up to dash ?
Yes , I do. Three times...speedo and two w/p guages |
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