Water Pressure relief valves
#1
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You guys running these valves........
With motor cold, (stat closed), is your water pressure running at your relief valve set pressure (18lbs) even while at idle or a tad higher?
With motor cold, (stat closed), is your water pressure running at your relief valve set pressure (18lbs) even while at idle or a tad higher?
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Some people are like Slinkies - Not really good for anything, but they
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#3
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US1, take a ride up to LaPorte some evening and I will take you out in the WETTE VETTE and show you how my relief works. I think you will like it. My pressure is about 3 to 5 psi at idle and about 20 to 23 at 90 mph plus. It is adjustable and I run a cross over and a thermostat that keeps the water in the block at 150 degrees. I am getting ready to put together about 10 kits. I want to see how much I could sell these for. Bring your boat and we can do some radar passes if you want. Consider it an open invitation.
#4
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WETTE VETTE,
I checked into the Deltrol valve pt# that you gave on another thread. From what I gathered, it is a flow control valve (volume), not a pressure relief valve. Is this correct? What is this system you are putting together?
I may have to give up on my own design. I can get temps up to 150* on the initial first warm up with a few pds of pressure, then I'll do some running around. Temp always drops and stays around 120*, with pressure max at 20psi. BUT here is where I get lost. When I go back to idle, temp will raise to 230*, (with some pressure), then pressure goes to 0, temps drops to 140*. This acts like the stat slams open fully at 230, which explains the pressure drop to 0 psi, and allows full water flow which is why the temp drops to 140*. Once back down to 140*, pressure comes back up to a few pds. (T-stat closing?) Then this cycle repeats over and over. Each of these cycle times are less than 1 min. 140-230-140> repeats. I can bump the throttle up a hair to which it will drop the temps back to 140* and stay, but at that idle speed, it is a bit to high for idle zones. SO this leads me to believe it is a flow problem.
I have tried 4 different stats, both types (high volume flow & reg flow) Holes, no holes. All same results. Don't see anyway for stats to get hung up inside the intake. Bypass hose comes off the crossover, goes thru the brass tee, and then gets dumped into the tee at the Gil risers. I'm using the Merc brass tee with the spring loaded plastic balls as my pressure relief regulator connected into the hose from the crossover to the riser tee. This should more or less be the same thing as an adjustable relief valve. I have tried different springs pressures on the plastic balls. Also diffent size plugs threaded into the inlet side of the brass tee for some flow control. In order for any cooled bypass water to travel back to the stat housing, it has to back flow thru the ex. manifolds which should "preheat" the water so it's not like it is shocking the stat with cold water.
Talk to me Goose!
Thanks,
Jerry
I checked into the Deltrol valve pt# that you gave on another thread. From what I gathered, it is a flow control valve (volume), not a pressure relief valve. Is this correct? What is this system you are putting together?
I may have to give up on my own design. I can get temps up to 150* on the initial first warm up with a few pds of pressure, then I'll do some running around. Temp always drops and stays around 120*, with pressure max at 20psi. BUT here is where I get lost. When I go back to idle, temp will raise to 230*, (with some pressure), then pressure goes to 0, temps drops to 140*. This acts like the stat slams open fully at 230, which explains the pressure drop to 0 psi, and allows full water flow which is why the temp drops to 140*. Once back down to 140*, pressure comes back up to a few pds. (T-stat closing?) Then this cycle repeats over and over. Each of these cycle times are less than 1 min. 140-230-140> repeats. I can bump the throttle up a hair to which it will drop the temps back to 140* and stay, but at that idle speed, it is a bit to high for idle zones. SO this leads me to believe it is a flow problem.
I have tried 4 different stats, both types (high volume flow & reg flow) Holes, no holes. All same results. Don't see anyway for stats to get hung up inside the intake. Bypass hose comes off the crossover, goes thru the brass tee, and then gets dumped into the tee at the Gil risers. I'm using the Merc brass tee with the spring loaded plastic balls as my pressure relief regulator connected into the hose from the crossover to the riser tee. This should more or less be the same thing as an adjustable relief valve. I have tried different springs pressures on the plastic balls. Also diffent size plugs threaded into the inlet side of the brass tee for some flow control. In order for any cooled bypass water to travel back to the stat housing, it has to back flow thru the ex. manifolds which should "preheat" the water so it's not like it is shocking the stat with cold water.
Talk to me Goose!
Thanks,
Jerry
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Some people are like Slinkies - Not really good for anything, but they
bring a smile to your face when pushed down the stairs.
Some people are like Slinkies - Not really good for anything, but they
bring a smile to your face when pushed down the stairs.
#5
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I would try to run a 1/4" line from your bypass tee directly to your thermostat housing. You are running it through your exhaust first which could be causing the erratic behavior. Remember flow follows the path of least resistance and at low RPM the low flow produced by your pump is possibly draining out the bottom of your exhaust tailpipes and not making it to your T-stat housing. When you bump your idle up the pump is putting out a little more flow and allowing some water to get to the T-stat housing. Try to tee in before the brass pressure relief and run a 1/4" hose to the thermostat housing and see what happens. I left the crossover just as it comes from Stainless and I bleed off some of the excess flow after the oil cooler which lowers the system pressure while not affecting the T-stat operation. I also run a 5 PSI relief at my sea strainer on the inlet side of the pump that gets rid of any pressure spikes that may occur from the drive exiting and re-entering the water. This relief doesn't have to be very large because of the fact that water is incompressible and a small volume dump will eliminate spikes before they get to the pump, strainer, or motor. If you continue to have problems keep in mind my open invitation to come on up to LaPorte. We will make it work very close to the way you have it now.
I forgot to mention that I have a Tool & Die shop available to me at any time. Custom fittings or whatever it takes. Good luck!!!
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Last edited by WETTE VETTE; 06-06-2002 at 09:49 AM.
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wette vette,
I also did a little research on that deltrol part number and cannot see where the water is dumped from. Am I missing something? I was thinking I would see an inlet port, oulet port and a dump port. The pressure relief valve I was contemplating was the McMaster-Carr 9763k49. My application is quite different in that I am running a jet drive where all the coolant water is taken directly from the drive creating potentially very high pressures at WOT. My solution was to install a tee into the main water feed of the pump. Screw in the above metioned relief valve into the tee side and plumb the pressure dump overboard. Like yours it is adjustable, from 0-50 psi. This seems to be nothing more than a high pressure blow off valve. An in line flow control valve makes me nervous since I do not run a strainer and would be afraid of the flow control valve becoming clogged. And we all know the result of that!! Any input on my idea?
US1, you may want to take a look at this relief valve.
Paul
I also did a little research on that deltrol part number and cannot see where the water is dumped from. Am I missing something? I was thinking I would see an inlet port, oulet port and a dump port. The pressure relief valve I was contemplating was the McMaster-Carr 9763k49. My application is quite different in that I am running a jet drive where all the coolant water is taken directly from the drive creating potentially very high pressures at WOT. My solution was to install a tee into the main water feed of the pump. Screw in the above metioned relief valve into the tee side and plumb the pressure dump overboard. Like yours it is adjustable, from 0-50 psi. This seems to be nothing more than a high pressure blow off valve. An in line flow control valve makes me nervous since I do not run a strainer and would be afraid of the flow control valve becoming clogged. And we all know the result of that!! Any input on my idea?
US1, you may want to take a look at this relief valve.
Paul
#7
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PB, the pressure relief valve is a good idea. The thing about a direct acting relief is it has to be sized properly. If it is to large it could chatter causing pressure spikes. If it is to small it may not have the capacity to lower the pressure enough. I tee the flow control into my main water feed line after my oil cooler, just as you described. I made a custom tee that goes in the 11/4" main line and run a 1/2 ID hose to the non pressure compensated flow control. It dumps a little water at idle and as the pump flow increases, more water dumps. It seems to work pretty well. If the pressure is to high I dump more water and vise versa. Try the relief and let us know how it works. My guess is something that can handle around 8 - 12 GPM with 1/2" or 3/4" ports. Oh ya, if dirt gets stuck in a relief it can fail as well. I suggest a strainer on all marine engines before the pump.
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pb-I bought a pressure relief valve from McMaster. If you're looking at the 1/2" one, it's proably the same. I havn't had a chance to even try it yet, but I'm thinking that I really don't want to go throught the hassel of trying to design a system. I'm thinking that I'm going to be returning it...
Wet Vette-tell me more about your system...
Wet Vette-tell me more about your system...
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cord,
I do not think that much design really needs to go into this. I am just plumbing a tee into my main line, installing the relief into the bullhead side of the tee and running the dump line back through the transom. Finally I will adjust the relief valve and let it do its thing.
I put a pressure guage in the intake manifold and the engine builder saw in excess of 30 psi at 4800 rpm. We quit there because we were lean. With the rejetting we are hoping around 5100 rpm meaning more pressure. Makes me and and the builder a little nervous.
I would like to hear more about vette's system as well.
Paul
I do not think that much design really needs to go into this. I am just plumbing a tee into my main line, installing the relief into the bullhead side of the tee and running the dump line back through the transom. Finally I will adjust the relief valve and let it do its thing.
I put a pressure guage in the intake manifold and the engine builder saw in excess of 30 psi at 4800 rpm. We quit there because we were lean. With the rejetting we are hoping around 5100 rpm meaning more pressure. Makes me and and the builder a little nervous.
I would like to hear more about vette's system as well.
Paul
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I am in the process of getting some costs so I can put about 10 kits together and sell them at a reasonable price. I would sell the adjustable flow control, special tee, through transom dump, and the necessary fittings. I would offer the inlet side spike reducer as an option and would offer the necessary components there as well. You would need to buy the appropriate length of 3/4" heater hose and hose clamps from your local parts store. A water pressure gauge is required and a sea strainer is highly recommended. Hey Cord and PB, you guys aren't to far away, take a ride to NW Indiana and check it out anytime. If nothing else you can go for a 95 MPH ride in the WETTE VETTE.
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