Mechanical water pressure kit.

[LONGPOND-RAY]

443370Looking for a part number for a mechanical water pressure kit for a 2014 Mercury 300xs offshore outboard. Could you please provide a quick breakdown on how to hook it up at the motor. Can I just t- off the gray water line? Thanks for your help and have a happy 4th of July!!!!

[SS Minnow]

T in a water pressure line will not yield accurate results. Dedicated line for pressure gauge. Sorry I am not familiar with your model though. Good luck.

[Gordon02]

I've been running T's for many years to water pressure gauges - tapped into the "pee tube/overboard indicator" lines. My gauge is not there for accuracy, but to prove pressure exist and to have an immediate, visual reference to previous and consistent pressures. If my gauge reads 13 lbs at 4,000 when it's actually 17 psi, I'm ok as long as I see that 13 lbs each time I'm out. Gordon

[SS Minnow]

I've been running T's for many years to water pressure gauges - tapped into the "pee tube/overboard indicator" lines. My gauge is not there for accuracy, but to prove pressure exist and to have an immediate, visual reference to previous and consistent pressures. If my gauge reads 13 lbs at 4,000 when it's actually 17 psi, I'm ok as long as I see that 13 lbs each time I'm out. Gordon
Do you run temp gauge as well? Just wondering. I started with a t and was not happy with how it worked at low rpm. As in it did not show pressure at low rpm. I fried a piston at low rpm this way and it was on a 79 tower 115.

[Gordon02]

My ProMax 200/Allison has both. The water pressure is fed by a dedicated line from the top of the exhaust divider (as seen below). It will not read any pressure until I get over 2,500 rpm. Mine is a 0~30 psi gauge, perhaps a 0~15 would be more accurate for idle. It's been that way since I rigged it myself new in 1999. At 3,000 and up, the pressure reads 13~15 psi and no more. I change/service my water pump with a new Mercury impeller every 2 years.

The temp gauge sender is only on one cylinder head, both heads have the warning horn circuit senders. The temp will not get over 100 at idle and that's where the gauge starts. I have to run near full-throttle for a few minutes to get temps to 135~140 degrees, but even at full throttle it will not go over the 150 degree mark. If I can only have one, I'll take the pressure gauge for monitoring. That is of course with a warning sender in each head/heads. I use my pressure gauge purely as a reference to the last time it was run.

443418

[nitro_rat]

I'm running a promax/260 divider on my 2.5 with the dedicated pressure port. My water pressure gauge is a mid 80's Mercury 30 psi gauge. It reads pressure at all rpm's, no issues. Maybe 5 pai at idle to 20 or so at speed. I have a new Teleflex temp gauge connected to the factory sensor in the head. My engine warms up to temp within a few minutes (140-ish) and stays pretty consistent with the running I do. All stock cooling system with stats in a modified 175 efi block now running carbs.