150 water pressure

[hl]

I believed my water pressure guage was going bad,it had water build up under the glass, so I replaced it with one from Basspro shop. The new one reads 5 psi at idle and about 12 to 14 at 3000-3500 RPMs with no increase to 4000-4500 RPMs. Sometimes the reading will flop back and forth between 10 to 20 psi. Could this be in the motor or the gage?

 

[j_martin]

Re: 150 water pressure

I believed my water pressure guage was going bad,it had water build up under the glass, so I replaced it with one from Basspro shop. The new one reads 5 psi at idle and about 12 to 14 at 3000-3500 RPMs with no increase to 4000-4500 RPMs. Sometimes the reading will flop back and forth between 10 to 20 psi. Could this be in the motor or the gage?

It's within spec. The flopping is probably the water pickups sucking a bit of air at full trim. If you trim it in a bit, it steadies out. It probably won't hurt anything as long as you have sufficient water (over 10psi)

 

[sschefer]

Re: 150 water pressure

I believed my water pressure guage was going bad,it had water build up under the glass, so I replaced it with one from Basspro shop. The new one reads 5 psi at idle and about 12 to 14 at 3000-3500 RPMs with no increase to 4000-4500 RPMs. Sometimes the reading will flop back and forth between 10 to 20 psi. Could this be in the motor or the gage?

What John say's is true. You may also be seing your poppet valve opening. As you increase RPM's from idle, right around 1500-1800 RPM the poppet valve begins to open. As you continue to increase RPM you'll see a rise in pressure then a sudden drop and a little bouncing then it will steady out and hold up around 10-12 lbs.

What John is talking about is a a swinging needle that doesn't settle down until you slow down and get the water pickups back into clean water.

I'm not a big fan of letting the latter problem go on. It also means your prop is very close to breaking the surface. Without the correct prop you can end up needng a very expensive L/U repair if the motor overheat doesn't get you first.

 

[hl]

Re: 150 water pressure

Thanks, I feel better with your replies. I still would like to install a temperture gauge. What is the best way to install a temperture gauge to the motor?

 

[j_martin]

Re: 150 water pressure

Thanks, I feel better with your replies. I still would like to install a temperture gauge. What is the best way to install a temperture gauge to the motor?

It probably already has the sending unit and wiring for a standard mercury water temp gauge, or any of the aftermarket gauges.

Look at the heads. On one is a sending unit with one wire. that's the OT sender. On the other is one that has 2 wires. That's the temp gauge sender.

hope it helps
John

 

[hl]

Re: 150 water pressure

Thanks John, you have been a great help