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Carl C
05-01-2010, 10:09 AM
I got my sea strainer but think i should get a water pressure pop-off too. What is the proper name for these things. How do they work? Do i drill a hole through the hull to dump excess water when the pressure reaches a certain point? I can't find them on Teaque's web site and would like to order it from them since i already have an order in the works there. I have closed cooling and Imco shorty and the pressure gets really high. TIA

yeller
05-01-2010, 10:51 AM
You want a pressure relief valve. I've never purchased one, but the first place I'd check would be your local plumblin supply store. Buying from a marine store, I can only imagine you'd pay much more.

Not sure where you'd plumb it to. Water exit lline??

To add to Carl's questions: How much pressure is to much (on the raw water side) for a sea strainer? I will be installing a strainer as well and I see over 50psi on the raw water side.

gcarter
05-01-2010, 11:37 AM
Carl, there's a lot of items that Teague doesn't carry, spend more time on the CP Performance site.......

http://www.cpperformance.com/c-121-pressure-relief-valves.aspx

Buy the 1 1/4" Tee and the relief valve. Insert the Tee into your supply line after the strainer and screw the relief valve into the Tee. Add a hose to the relief valve and route it through the transom w/a bulkhead fitting (available a number of places, maybe CP, I haven't looked).
If you find you have lots of water going out the relief valve, you can use it for the shower.
Get a water pressure gauge, use the oil cooler drain for the pressure source.
Adjust the relief valve to max out at whatever your minimum is.

gcarter
05-01-2010, 11:42 AM
I just noticed the range is 7#-25#.
You should be able to find a stiffer spring if that's too low.
This is a neat little package.

Carl C
05-01-2010, 11:49 AM
You want a pressure relief valve. I've never purchased one, but the first place I'd check would be your local plumblin supply store. Buying from a marine store, I can only imagine you'd pay much more.
Not sure where you'd plumb it to. Water exit lline??
To add to Carl's questions: How much pressure is to much (on the raw water side) for a sea strainer? I will be installing a strainer as well and I see over 50psi on the raw water side.

My gauge is usually pegged now but the 525 does like more pressure. I just don't want to go too high and blow something out on the raw water side.


Carl, there's a lot of items that Teague doesn't carry, spend more time on the CP Performance site.......

http://www.cpperformance.com/c-121-pressure-relief-valves.aspx

Buy the 1 1/4" Tee and the relief valve. Insert the Tee into your supply line after the strainer and screw the relief valve into the Tee. Add a hose to the relief valve and route it through the transom w/a bulkhead fitting (available a number of places, maybe CP, I haven't looked).
If you find you have lots of water going out the relief valve, you can use it for the shower.
Get a water pressure gauge, use the oil cooler drain for the pressure source.
Adjust the relief valve to max out at whatever your minimum is.

My entire transom is cored, how about drilling through the hull side next to the bilge pump through-hull? The shower thing would work except that when i am running hard i have my drive trimmed up and pressure drops. That would mean no drive shower water when it is needed the most.

Thanks for the info, i will look for the part. George, i was the victim of credit card fraud recently and like to use my card on as few sites as possible.

Carl C
05-01-2010, 12:04 PM
Yes, George I need more pressure than that. I checked Teague again and can't find one.

Yeller, I'm all for saving a buck but my boat is one thing i will not cut corners on. It gets only the best. The sea strainer was $400 but is SWEET!. I now have over $91,000 into this little hot-rod not counting maintenance or repairs.

gcarter
05-01-2010, 12:08 PM
Just a reminder, you'll always lose pressure at high trim levels unless you use a transom pickup.

Also, you'll find a lot of relief valves in different pressure ranges, just do a search. You'll end up in some industrial plumbing supply sites.
But the Tee from CP is a nice part.

Carl C
05-01-2010, 12:15 PM
Just a reminder, you'll always lose pressure at high trim levels unless you use a transom pickup.

Also, you'll find a lot of relief valves in different pressure ranges, just do a search. You'll end up in some industrial plumbing supply sites.
But the Tee from CP is a nice part.

I had posted a thread about that and i did a little grinding on the water pick-up and it seems to have helped. Now my concern is too much pressure at lower trim levels. Everyone tells me that the Imco shortys are notorious for too much pressure.

Carl C
05-01-2010, 12:44 PM
BTW i need to run 30-50 psi on the raw water side. The 525 likes that. I will set the relief valve at 45-50 psi. Still looking for one.

mrfixxall
05-01-2010, 01:53 PM
BTW i need to run 30-50 psi on the raw water side. The 525 likes that. I will set the relief valve at 45-50 psi. Still looking for one.


thease are adjustable

http://www.cpperformance.com/c-121-pressure-relief-valves.aspx

Carl C
05-01-2010, 01:57 PM
thease are adjustable

http://www.cpperformance.com/c-121-pressure-relief-valves.aspx

Looks like 7-25 psi :( . I need higher. Unless I'm overlooking something. I've been told by trusted sources that I need to run 30-50 psi at WOT with the 525.

BTW I'm not expecting you guys to do my leg work for me. I'm at work right now so can't really search until tonight. BUT, if anyone knows a source....... :)

Michi Besler
05-01-2010, 02:15 PM
I got mine from Livorsy (as far as I remember it is from about 30psi to 150psi) I can check it over the weekend If you like?
I have put the valve straight to the intercooler sandstrainer. The relieved water goes behind the intercooler thrue a Tee fitting in the draine hose (thru hull). The white hose on the strainer goes to the pressure gauge.

yeller
05-02-2010, 04:26 AM
Yeller, I'm all for saving a buck but my boat is one thing i will not cut corners on. It gets only the best. I probably shouldn't have said "plumbing supply store". Conjures up images of Homedepot and such. I'm talking mechanical supply stores. What you get from them won't be of lesser quality. In fact, I'd question the quality of a relief valve from a marine store over one from a mechanical supply store.

If you truly want the "best", I use to purchase units that were installed in ULTRA critical monitoring situations at $1500 apiece. :eek!:

Carl C
05-02-2010, 07:27 AM
I got mine from Livorsy (as far as I remember it is from about 30psi to 150psi) I can check it over the weekend If you like?
I have put the valve straight to the intercooler sandstrainer. The relieved water goes behind the intercooler thrue a Tee fitting in the draine hose (thru hull). The white hose on the strainer goes to the pressure gauge.

Thanks, I will look at Livorsi's web site when I have the time.


I probably shouldn't have said "plumbing supply store". Conjures up images of Homedepot and such. I'm talking mechanical supply stores. What you get from them won't be of lesser quality. In fact, I'd question the quality of a relief valve from a marine store over one from a mechanical supply store.
If you truly want the "best", I use to purchase units that were installed in ULTRA critical monitoring situations at $1500 apiece. :eek!:

I just want to be sure to get a marine grade product. Here are pics of the sea strainer. Just the wing nut option was about $50! The two fittings were about $41 each. Grand total near $400 but worth every penny to me! (and in Merc Racing blue, yay)

MOP
05-02-2010, 08:04 AM
Carl one of my friends has two of those wing nut strainers, I can not tell you how much he hates them. Says worse than any gal he has ever met, they don't hold much plus having to remove 8 wing nuts to clean is a pain pretty but not user friendly!

Carl C
05-02-2010, 08:11 AM
Carl one of my friends has two of those wing nut strainers, I can not tell you how much he hates them. Says worse than any gal he has ever met, they don't hold much plus having to remove 8 wing nuts to clean is a pain pretty but not user friendly!

How long can it take to loosen 8 wing nuts :confused:. I don't expect to have to clean it daily and now I don't need to worry about having an allen wrench on board.

gcarter
05-02-2010, 08:21 AM
What Phil said.
Use a Perko 1 1/4". It has two wing nuts that you only have to loosen and the basket can be out in under 5 seconds. Also the basket size is at least a quart.
These high priced billet pieces aren't necessarily the best, they;re just designed to look good.
You can paint the Perko piece any color you want. They're bronze and will last almost indefinately.
Worst case scenario;
You just sucked up a lot of mud and weeds and your temp gauge is headed to the moon. You kill the engine but you're in a current and your bearing down on some other boats. What happens while you're undoing all those wing nuts?
Is your insurance paid up?
With the Perko, you jump in the back seat, raise the hatch, loosen the two wing nuts, swing the lid out of the way, lift out the basket and rinse it out, reinstall, and it's only taken about 15-20 seconds since you killed the engine.
How do I know this?
Believe me when I tell you I was glad to have the Perko!

http://ct3.pbase.com/g3/84/622984/3/108222831.Mfhh9Xcj.jpg (http://www.pbase.com/mainecruising/image/108222831)

Carl C
05-02-2010, 08:55 AM
I'm not sending it back! I can loosen the wing nuts in seconds. No searching for an allen wrench at least.

gcarter
05-02-2010, 08:57 AM
I'm not sending it back! I can loosen the wing nuts in seconds. No searching for an allen wrench at least.

Don't you mean "remove and drop in bilge"?

MOP
05-14-2010, 04:19 PM
Carl I hope you read this! I spent a fair portion of the day watching and BSing with the owner of Hustler Boats, I noticed a hose wire tied to the transom that looked like a dump I asked about it was to relieve the excess water pressure. He runs his 525's between 25 & 30 psi MAX, he said that is more than enough there are blower motors out there running 20 psi. Pop a hose a 50 psi you will put tons of water in the bilge, running 50 is just plain nuts. With wet exhaust you will lose a fair bit of top end, I can attest to that I lost quite a bit swapping to the crank pump which pumps like a fire engine. Relief valve going in soon!

Carl C
05-14-2010, 04:51 PM
Don't you mean "remove and drop in bilge"?

Nope. They are wing bolts that come loose but cannot come out of the lid.


Carl I hope you read this! I spent a fair portion of the day watching and BSing with the owner of Hustler Boats, I noticed a hose wire tied to the transom that looked like a dump I asked about it was to relieve the excess water pressure. He runs his 525's between 25 & 30 psi MAX, he said that is more than enough there are blower motors out there running 20 psi. Pop a hose a 50 psi you will put tons of water in the bilge, running 50 is just plain nuts. With wet exhaust you will lose a fair bit of top end, I can attest to that I lost quite a bit swapping to the crank pump which pumps like a fire engine. Relief valve going in soon!

I ran into some problems with the installation. The 1 1/4" hose is too rigid and I broke the plastic inlet off the raw water pump. Now I have on the way from CP Performance: stainless steel water pump housing with screw in fittings, variety of angled fittings, new high pressure inlet hose, PRESSURE RELIEF VALVE!, T fitting, 5/8 dump hose and SS through-hull. Will post pics when done. I will run 25 psi on the raw water side which I have been told is sufficient.

Cuda
05-14-2010, 05:09 PM
The sea strainers in my Formula had two wing nuts, and a "bar" running between them. If you loosened just one nut, you could swing the bar around and open the strainer. I think they were Jabsco. I know that's who made the bilge pump. It wasn't Merc Blue though, just brass.

Carl C
05-14-2010, 05:15 PM
The sea strainers in my Formula had two wing nuts, and a "bar" running between them. If you loosened just one nut, you could swing the bar around and open the strainer. I think they were Jabsco. I know that's who made the bilge pump. It wasn't Merc Blue though, just brass.

This is going to look so cool. I got my Merc Racing Blue billet battery boxes from Teague today. I'm doing my part to help the economy! :)

Brian41
05-14-2010, 05:19 PM
Carl after the first time of reaching down and cleaning the sea strainer you will change your mind about it. I just ordered a Hardin Marine strainer to replace the same one you have on Carl Chase's boat. Its all stainless with a large T-handle and it will match your exhaust.

yeller
05-14-2010, 08:19 PM
Carl, post some pics of the installation.....even though it's not 100% yet. Interested in where you mounted yours.

Carl C
05-14-2010, 09:07 PM
Carl, post some pics of the installation.....even though it's not 100% yet. Interested in where you mounted yours.

This is where I'm at. The hose to the pump is a mock up. I can't use automotive hose. I made an aluminum bracket to extend the built in bracket down and it bolts to the stringer with two SS screws and sealant. It rests on the shelf on a piece of rubber sheet that I glued to the bottom of the strainer. I unhooked the header hose for this pic. This will look a lot different when it's done.

Cuda
05-14-2010, 09:17 PM
You couldn't get $400 out of me with a gun for a sea strainer.

Carl C
05-14-2010, 09:32 PM
I've got $92,000 into the boat now not counting repairs or maintenance. Check these out :) :

MOP
05-15-2010, 07:12 AM
Carl make 100% sure that the top of the strainer is above the water line with you back there cleaning it, your install looks low nothing like water gushing in. My strainer is close to over flowing with my skinny butt back there, also notice the simplicity of one wing nut plus the non bling corrosion, bullet proof construction. Those need the bling can get one of these chrome plated.

Tborisch
05-15-2010, 07:31 AM
So this thread raises an interesting question for me. If i don't open up the water pickup like Carl did on his lower, and just leave it the way it comes from the factory, and I'm running my 496HO at a top speed of 75 mph, should i have to worry about using a pressure release valve? My stock bravo lower has the side pickups, and the lower pickup.. and makes about 38 pounds of raw water pressure. I would think the imco would make about the same pressure as my bravo with the lower and side pickups.

I'm not anxious to be the next guy to have a $92,000.00 22 classic. I still want to have a skater some day :)

Tom

MOP
05-15-2010, 07:42 AM
Randy (Big Griz) stated that a transom pickup generates more pressure than the drive, the drive water passages and where it comes though the shield is smaller restricting volume compared to the transom setup. That being said the transom setup is 100% more reliable, it does away with the worry of the hose between the drive and shield going bad. My kid went through two hoses in three seasons with a lot of usage, they are a real pain and can be bloody to replace. Done by a shop can be close in $$ to installing a transom unit. Phil

Carl C
05-15-2010, 07:59 AM
So this thread raises an interesting question for me. If i don't open up the water pickup like Carl did on his lower, and just leave it the way it comes from the factory, and I'm running my 496HO at a top speed of 75 mph, should i have to worry about using a pressure release valve? My stock bravo lower has the side pickups, and the lower pickup.. and makes about 38 pounds of raw water pressure. I would think the imco would make about the same pressure as my bravo with the lower and side pickups.
I'm not anxious to be the next guy to have a $92,000.00 22 classic. I still want to have a skater some day :)
Tom

The Imcos are notorious for excessive water pressure at lower trim settings. Being closed cooled any damage would be limited to the raw water side but still I'd install a relief valve. Here is what I have on the way (the first two items on the page). It will easily splice into your existing raw water hose. You'll also need a through hull and 5/8 hose. Our transoms are fully cored so I will dump out the hull side.http://www.cpperformance.com/c-121-pressure-relief-valves.aspx

You can probably find cheaper but I try to buy the best ;)

undertaker
05-15-2010, 09:18 AM
Carl after the first time of reaching down and cleaning the sea strainer you will change your mind about it. I just ordered a Hardin Marine strainer to replace the same one you have on Carl Chase's boat. Its all stainless with a large T-handle and it will match your exhaust.


Brian, which one did you get for Carl Chase boat, looked on their site and they have a few to choose from....just curious....thanks..

Undertaker:pimp:

Tborisch
05-15-2010, 09:50 AM
The Imcos are notorious for excessive water pressure at lower trim settings. Being closed cooled any damage would be limited to the raw water side but still I'd install a relief valve. Here is what I have on the way (the first two items on the page). It will easily splice into your existing raw water hose. You'll also need a through hull and 5/8 hose. Our transoms are fully cored so I will dump out the hull side.http://www.cpperformance.com/c-121-pressure-relief-valves.aspx

You can probably find cheaper but I try to buy the best ;)

Hmmm.. Thanks for the lead. I think those parts look like standard hydraulic stuff. I'm going to hit up bond fluid air here in town before I order. They will probably have slot of that same stuff
cheaper.

If not, I will order that stuff.

I can't fathom a need for a sea strainer in my boat.. I always run in freshwater lakes, and typically stay away from areas you would pick something up. Been running boats with no strainers for 20 years on the same lakes.. Why start now :)

Tom

Tborisch
05-15-2010, 09:52 AM
Hey Carl, were are you going to get the thru hull fitting from?

Tom

Carl C
05-15-2010, 09:58 AM
Hey Carl, were are you going to get the thru hull fitting from?
Tom

A stainless steel one is also coming from CP Performance.

Tborisch
05-16-2010, 08:40 PM
So, better to put the relief valve before or after the raw water pump?

I'm thinking before.... right?

Tom

Carl C
05-24-2010, 08:30 PM
So, better to put the relief valve before or after the raw water pump?
I'm thinking before.... right?
Tom

Yes, between the sea strainer and raw water pump. I got mine done today. I now have a solid SS raw water pump :). The rear through-hull is the water dump. I decided on this location after a lot of discussion about it.

thehow33
05-24-2010, 10:31 PM
I like the location....looks uniform. and less hose in the bilge if you were thinking about putting it on the other side port side. And i'm jealous of that awesome water pump

MOP
05-25-2010, 06:08 AM
Carl hate to say it but all the info I found over the last couple of years says valves after the oil cooler, the reasoning is when the valves open they increase flow through cooler when your engine needs it most have not seen. I was going down the same road, had the fittings made up to go into the intake hose just after my strainer that would dump the excess onto the top of my drive. I explained it to a couple of folks that I know that race they told me I was nuts and to ditch the idea and go after the oil cooler, so no my drive will get a little warmer water.

Phil

Carl C
05-25-2010, 07:10 AM
Carl hate to say it but all the info I found over the last couple of years says valves after the oil cooler, the reasoning is when the valves open they increase flow through cooler when your engine needs it most have not seen. I was going down the same road, had the fittings made up to go into the intake hose just after my strainer that would dump the excess onto the top of my drive. I explained it to a couple of folks that I know that race they told me I was nuts and to ditch the idea and go after the oil cooler, so no my drive will get a little warmer water.
Phil

As usual opinions will vary but this guy races: http://seriousoffshore.com/forums/showpost.php?p=494871&postcount=3

Cuda
05-25-2010, 07:41 AM
Opinions are like buttholes: Everybody has one, and they all stink. :)

MOP
05-25-2010, 07:54 AM
As usual opinions will vary but this guy races: http://seriousoffshore.com/forums/showpost.php?p=494871&postcount=3

Carl you are F/W like I am you are also loosing flow to your exchanger!
http://www.offshoreonly.com/forums/general-q/193960-water-pressure-w-imco-shorty-vs-stock-lower.html Read #2
http://www.offshoreonly.com/forums/general-q/190276-where-install-dana-pop-off-valve-496-ho.html Read #3
http://www.offshoreonly.com/forums/general-q/108289-who-sells-raw-water-pressure-releif-valves-4.html Read #31 It is not an opinion just simple logic, reducing flow to items that have critical need at speed does not make sense. I know quite a few put relief valves at the strainer but if you read the posts they are raw cooled, closed needs the flow. At high speed is where your engine develops the highest temps, that is when it needs maximum flow the most.

Tborisch
05-25-2010, 08:45 AM
So, what hose number here are you saying to install the relief valve on? 11?

http://www.boats.net/parts/search/Merc2/Mercruiser/496%20MAG%20%28H.O.%20Model%29/0M687144%20THRU%200W059999/Raw%20Water%20Cooling%20System/parts.html



Thanks.
Tom

Carl C
05-25-2010, 08:47 AM
Carl you are F/W like I am you are also loosing flow to your exchanger!

I'm not limiting flow; Only excess pressure. I did not add any restrictions to flow.

MOP
05-25-2010, 09:17 AM
[quote=Carl C;566722]I'm not limiting flow; Only excess pressure.
Carl you are 100% correct in that statement! Now by allowing the excess water to flow out of the system you do increase flow up to the point of where the pressure relief valve is installed but after that point you reduce the flow!

Carl C
05-25-2010, 10:28 AM
[quote=Carl C;566722]I'm not limiting flow; Only excess pressure.
Carl you are 100% correct in that statement! Now by allowing the excess water to flow out of the system you do increase flow up to the point of where the pressure relief valve is installed but after that point you reduce the flow!

Honestly I don't follow that logic. The valve will only open above 25 psi. When running wide open with some positive trim I am only seeing about that now so the relief valve should rarely open when running hard. I still have a straight run of 1 1/4" hose to the pump although it now runs through the sea strainer. The valve should only open to relieve the super high pressure that the Imco lower provides at lower trim angles. To install the relief valve anywhere but in front of the raw water pump really doesn't make sense to me:confused:.

Pismo
05-25-2010, 11:59 AM
There is a common misconception that pressure and flow are the same, ie more pressure equal more flow. This is not always true such as if you had an outlet obstruction, you would have high pressure and low flow. Flow, not pressure, takes away heat.

Carl C
05-25-2010, 04:42 PM
I got out today and the pump failed to prime itself at the dock. I was watching the sea strainer. I quickly got moving a bit and the water started flowing and everything went well today except for a small drip from a pump fitting which I will reseal. Pressure never exceeded 25 psi. Here is something I have never seen before on Lake Oakland. I wonder if anyone complained about the noise ;).
http://www.youtube.com/watch?v=IhbvDSuZVrM

BUIZILLA
07-11-2010, 08:02 PM
Yes, between the sea strainer and raw water pump. I got mine done today. I now have a solid SS raw water pump :). The rear through-hull is the water dump. I decided on this location after a lot of discussion about it. Carl, that won't fit a 330....

Carl C
07-11-2010, 08:45 PM
Carl, that won't fit a 330....

OK, I wasn't sure. They do fit a lot of engines.