SoCal Jet Boats

Tech Talk => Jet Pumps => Topic started by: Legal Chemistry on June 24, 2008, 02:20:37 PM

Title: Calibrate Pressure Relief Valve (watkins)
Post by: Legal Chemistry on June 24, 2008, 02:20:37 PM
What the best way to do it?

My guess is to attach a pressure gauge to the inlet set the air at 20 or 30# and twist till it drops to 18# and begins to bleed out?  My question being, will the air bleed the same as water?
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: jet boat performance on June 24, 2008, 08:50:27 PM
We created a "manifold" with a pressure guage to do just that and yes pressure is pressure ,your correct Tom
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: Jetaholic on June 24, 2008, 09:28:50 PM
What the best way to do it?

My guess is to attach a pressure gauge to the inlet set the air at 20 or 30# and twist till it drops to 18# and begins to bleed out?  My question being, will the air bleed the same as water?

Second that, set it with air so that it's just starting to open at 12psi.
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: Legal Chemistry on June 25, 2008, 11:38:23 AM
Thanks for the feedback. 

I already have a gauge set up to check for pipe leaks -this should be a quick.  I agree pressure is pressure, but with my luck some how this sh!t would have to be different for some crazy jet boat reason   ;D
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: Josh@JBP on June 25, 2008, 12:30:03 PM
Thanks for the feedback. 

I already have a gauge set up to check for pipe leaks -this should be a quick.  I agree pressure is pressure, but with my luck some how this sh!t would have to be different for some crazy jet boat reason   ;D

The only difference you may see is that the air may cause the gauge to flutter slightly because air compresses and water does not (preasure builds, releases... so on, so on).  
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: Legal Chemistry on June 26, 2008, 10:01:45 AM
good call.  I'll do it this evening.  if it works and anyone else (for whatever reason) needs this done in SD -I'll be more than willing.
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: 19ftCheyenne on June 26, 2008, 02:43:01 PM
what should they be set at? 18psi?
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: Jetaholic on June 27, 2008, 12:04:01 AM
what should they be set at? 18psi?

I set mine with air so that it is just starting to open at 12psi. Lots of WOT runs and no water in the oil 40 hours later.
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: Legal Chemistry on July 20, 2008, 01:32:25 PM
I finally got around to uploading some pics...

(https://www.socaljetboats.com/cpg/albums/userpics/10520/normal_gauge.JPG)

I'll etch these later so I can have an estimate of 12, 16, and 20#
(https://www.socaljetboats.com/cpg/albums/userpics/10520/normal_gauge_lines.JPG)

Set to ~18#
(https://www.socaljetboats.com/cpg/albums/userpics/10520/normal_gauge_at_18%23.JPG)
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: 2savage4you on July 20, 2008, 02:36:39 PM
Thanks for posting this thread , im getting ready to install my new valve and have a good idea of it now :D

2sav
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: realHawaiianJet on July 20, 2008, 09:09:49 PM
Yeah, I never even thought about adjusting the valve before installing it. :banghead: I will be putting one on my boat soon, when I switch the plumbing system to all AN lines. Already wrote down all the part numbers for my entire plumbing system just need to set aside the money. The only brass piece will be my pressure regulator! O0
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: Mark on July 21, 2008, 07:22:27 AM
Do you need to install the relief valve only if you're running a thermostat in the housing?  Seems like without a major restriction in the water path it would be hard to build that much pressure up through the block, heads, and exhaust manifolds (Sh.t through a goose kind of thing).

Cheers, Mark
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: Jetaholic on July 21, 2008, 08:32:40 AM
Set to ~18#


Where did you get 18 as the magic number?
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: Jetaholic on July 21, 2008, 08:39:33 AM
Do you need to install the relief valve only if you're running a thermostat in the housing?  Seems like without a major restriction in the water path it would be hard to build that much pressure up through the block, heads, and exhaust manifolds (Sh.t through a goose kind of thing).

Cheers, Mark


The whole purpose of the relief valve is so that you can run the water from the pump to the motor full on (no gate or ball valve restricting it) without overpressurizing the motor, blowing gaskets and getting water in the oil. However, on this setup, without the thermostat the engine will run way too cold. So...

The whole purpose of running a thermostat is to raise the temp of the motor up. On an unrestricted setup the engine would run too cold so the thermo serves to raise the engine temp up to 140* or so.
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: Mark on July 21, 2008, 10:08:13 AM
Thanks! 

Does the engine then get the regulated water supply and the exhaust manifolds get unrestricted flow?  Can you build up excessive heat in the exhaust manifolds and rubber tubing to the exhaust tips while waiting for the thermostat to open? 

What temperature of thermostat is recommended?  I see 140* mentioned, any guidelines for choosing the temperature?  This is primarily a Havasu boat.

I'll be plumbing the intercooler's heat exchangers as well.  I assume these want a continuous but pressure limited supply of filtered cool water.  If I "T" off the water supply after the pressure relief do I need to add a gate valve or some type of restrictor for the intercooler supply?

Apologies for all the questions.

Regards, Mark
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: realHawaiianJet on July 21, 2008, 09:40:40 PM
Thanks! 

Does the engine then get the regulated water supply and the exhaust manifolds get unrestricted flow?  Can you build up excessive heat in the exhaust manifolds and rubber tubing to the exhaust tips while waiting for the thermostat to open? 

What temperature of thermostat is recommended?  I see 140* mentioned, any guidelines for choosing the temperature?  This is primarily a Havasu boat.

I'll be plumbing the intercooler's heat exchangers as well.  I assume these want a continuous but pressure limited supply of filtered cool water.  If I "T" off the water supply after the pressure relief do I need to add a gate valve or some type of restrictor for the intercooler supply?

Apologies for all the questions.

Regards, Mark

Do you have log style manifolds on your engine??? ??? If you do then that plumbing setup is a little different than the setup for injected headers.

For wet headers, the only reason to plumb it so that the headers get unregulated cold flow, is if you have a Banderlog Valve. Otherwise, a small portion of the water is feed to the headers from the intake manifold, where the water is exiting.

http://www.socaljetboats.com/index.php?topic=3601.0 (http://www.socaljetboats.com/index.php?topic=3601.0)

http://www.socaljetboats.com/index.php?topic=4220.0 (http://www.socaljetboats.com/index.php?topic=4220.0)
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: Legal Chemistry on July 22, 2008, 11:52:27 AM
edited the link so the pics are bigger.
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: GAWnCA on July 22, 2008, 12:27:03 PM
Just a quick question about setting the relief valve, will sand or something else cause the valve to stick open too much?
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: beerjet on July 22, 2008, 02:58:56 PM
I was under the impression that a gate valve was always installed as close to the pump as possible in case a line ruptures and you had means of turning the water off so's not to flood your boat .

-beerjet-

ps. I've only ever ran a gate valve with no issues too. Carry on .
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: 19ftCheyenne on July 22, 2008, 03:07:45 PM
you want a ball valve coming right off the pump all the way open, then u end up using a gate valve before the t for your headers.
(https://www.socaljetboats.com/proxy.php?request=http%3A%2F%2Fi36.tinypic.com%2Fqz5ape.jpg&hash=d31f82b0415b6a5d88bc590dace83ed231b0b202)
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: beerjet on July 22, 2008, 09:18:13 PM
I dont know man  :-\ That looks like some roto-rooter type shit there .

-beerjet-
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: Legal Chemistry on July 23, 2008, 10:25:59 AM
I used 18# for illustration purposes.  18# is a typical 454 truck.  The 12-16-18 marks will let me know relatively where I'm at if it get bumped or needs to change.  With this particular part # the range is pretty close on the dial.

If anyone wants this done in the SD area (or mail it SASE) send it my way.  givin' a little back to the community and chit.
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: 19ftCheyenne on July 23, 2008, 10:28:04 AM
thats the thermostat housing kit they sell from rex. its the only way to go man!!! keeps my boat running at 160 and it blows any water pressure over 18psi overboard and you never have to adjust the water to the headers after you dial it all in. its perfect  ;D
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: 2savage4you on July 23, 2008, 11:54:38 AM
I didn't put my valve at the end like in the pic above, it is more like in line........If i need to fix it i can, i have not mounted it in yet cause i still need to pull the engine out one more time ;D
(https://www.socaljetboats.com/proxy.php?request=http%3A%2F%2Fi223.photobucket.com%2Falbums%2Fdd269%2F2savage4you%2F001-53.jpg&hash=3af8d6b380603b704e5f3b38bc39703934d1a721)
if this is ok , let me know ??? thanks....
2sav
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: 19ftCheyenne on July 23, 2008, 12:08:59 PM
so you took out the first ball valve from the pump and went straight to the T ? hard to tell from that one pic. put some more up when u get a chance, im interested in seeing how you ran it all.  ;D
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: 2savage4you on July 23, 2008, 12:26:25 PM
so you took out the first ball valve from the pump and went straight to the T ? hard to tell from that one pic. put some more up when u get a chance, im interested in seeing how you ran it all.  ;D

 No not my ball valve , that was replaced with a new one . I was talking about my pressure valve ;D

(https://www.socaljetboats.com/proxy.php?request=http%3A%2F%2Fi223.photobucket.com%2Falbums%2Fdd269%2F2savage4you%2F002-35.jpg&hash=c0899aa4c9320d9d3d43393a467ec8eebc20b571)
2sav
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: 19ftCheyenne on July 23, 2008, 12:29:52 PM
from what i see it all looks good to me  ;D   , were you gonna try and make it to martinez?
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: 2savage4you on July 23, 2008, 12:31:43 PM
from what i see it all looks good to me  ;D   , were you gonna try and make it to martinez?

No my boat don't run and never will ;D

J/k  right now im waiting on my order from jegs...... all new wires. should be running in a week maybe two...

2sav
Title: Re: Calibrate Pressure Relief Valve (watkins)
Post by: realHawaiianJet on July 23, 2008, 02:36:54 PM
should be running in a week maybe two...

I've been saying that for the last 8 months. :banghead: :banghead: :banghead:
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