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-   -   Water pressure too high? (https://www.offshoreonly.com/forums/general-q/327152-water-pressure-too-high.html)

payuppsucker 06-10-2015 07:43 AM

[QUOTE=minxguy;4315568]

Originally Posted by 1BIGJIM (Post 4315400)
.
. And they dump water over 1,500 rpms out of gear....

Are you saying the mercury valves dump water? I hope that is what you are saying because I installed one on a 454/385 hp and water was flowing out the side at an idle.

Thought the spring was bad, Took the valve off the boat, but if this is normal, I will reinstall.

Ken

Yes, That's normal.

payuppsucker 06-10-2015 08:13 AM

Hey Jim, your PM box is full.

cdaniel525 06-10-2015 04:03 PM

1 Attachment(s)

Originally Posted by fbc25el (Post 4315133)
That's how mine are. You drill the holes in the vertical center part just above the flange part . 2-3/16 holes.

Duly noted.... Ill do this for the hell of it to make sure tiny bit of water flow in front of block.


Originally Posted by BenPerfected (Post 4315256)
Do you have a pic of your setup by any chance?

Pic below... its the same thing on both sides at the rear of the manifold, into a Tee and dumped thru the transom



Originally Posted by 1BIGJIM (Post 4315400)
You are making this harder than it needs to be. Run a water pressure relief valve and be done with it. Holes in T-stat have nothing to do with pressure, I have two small holes in each t-stat and see 140-160 with a 140 t-stat.
.
I have a plastic merc valve with a small crack 1/4 long that sprayed a mist. I think it could be ground down and fixed. For $15 I will mail it to your door and you can try it. I even have pictures of the small crack. I run the ones from CP like you have shown. You need to get the pressure down, I never see over 25lbs on either engine at full throttle. And they dump water over 1,500 rpms out of gear....

Why did you change to a cross over?

Thanks for the offer on the plastic valve... I went ahead and pulled the trigger on the brass relief valve, a 1/2 npt to 3/4 hose, and water dump.... Figured its not worth messing around with, esp after reading else where that the high water pressure can cause water to blow by some gaskets and cause milkshake oil??? Is this true?



[ATTACH=CONFIG]542010[/ATTACH]

1BIGJIM 06-10-2015 06:27 PM


Originally Posted by cdaniel525 (Post 4315865)
Duly noted.... Ill do this for the hell of it to make sure tiny bit of water flow in front of block.



Pic below... its the same thing on both sides at the rear of the manifold, into a Tee and dumped thru the transom




Thanks for the offer on the plastic valve... I went ahead and pulled the trigger on the brass relief valve, a 1/2 npt to 3/4 hose, and water dump.... Figured its not worth messing around with, esp after reading else where that the high water pressure can cause water to blow by some gaskets and cause milkshake oil??? Is this true?



[ATTACH=CONFIG]542010[/ATTACH]

Buy a water pressure gauge also. Cleared PM's weird, says I had 80 and only 50 allowed.

Are you putting the valve on the intake manifold??

cdaniel525 06-10-2015 06:29 PM


Originally Posted by 1BIGJIM (Post 4315928)
Buy a water pressure gauge also. Cleared PM's weird, says I had 80 and only 50 allowed.

Currently have a mechanical water pressure gauge with hook up at the front of intake manifold... Is that sufficient

BenPerfected 06-10-2015 07:44 PM

For most boating a WP gauge at the engine should suffice. When we redid the dash a few years ago, we added WP gauges and they are definitely useful on the West side of Lake Erie due to the amount of weed in the last few years. If our WP drops to less than 5 lbs(?) and the engine temps start to rise, it is time to stop and remove the weed in the sea strainers. We also have a high water temp sender in our total alarm system. Old school, but if the alarm buzzer goes off, you hunt the dash for the problem.

minxguy 06-11-2015 06:29 AM

Payup, thanks for the answer.

I guess I will re-install the valve.

Ken

1BIGJIM 06-11-2015 06:39 AM

I meant to say are you putting the pressure relief valve on the intake manifold?

payuppsucker 06-11-2015 01:14 PM

CP has a 1 1/4 inch slip on union with a 1/2 npt fitting in the center for mounting the press reg valve. This should go in the rubber hose that goes from sea pump outlet to the engine, preferably near the pump itself.

payuppsucker 06-11-2015 01:19 PM


Originally Posted by minxguy (Post 4316114)
Payup, thanks for the answer.

I guess I will re-install the valve.

Ken

No problem bud.


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