Water pressure gauge install feedback

Moody Blue

Captain
Joined
May 24, 2004
Messages
3,136
Early in the season I installed a 0-15PSI pressure gauge on my 1971 Merc 800. Had just installed a new impeller and pump housing so I was getting the best performance out of the pump. I installed it in-line in the telltale hose. For all intent and purpose the gauge was useless. Only at WOT would the gauge read about 2-3 PSI.

I then decided to connect it to the port on the waterjacket cover (between cyl 2 and 3) to see if I could get any better results. I also have a temp gauge so I installed a T into the port on the waterjacket cover and connected the pressure line to one side and the temp sender to the other side.

So much better now. At idle I see about 2-3 PSI and at WOT about 12 PSI. Now I have a usable gauge.
 

daveswaves

Ensign
Joined
Mar 22, 2002
Messages
901
Re: Water pressure gauge install feedback

Early in the season I installed a 0-15PSI pressure gauge on my 1971 Merc 800. Had just installed a new impeller and pump housing so I was getting the best performance out of the pump. I installed it in-line in the telltale hose. For all intent and purpose the gauge was useless. Only at WOT would the gauge read about 2-3 PSI.

I then decided to connect it to the port on the waterjacket cover (between cyl 2 and 3) to see if I could get any better results. I also have a temp gauge so I installed a T into the port on the waterjacket cover and connected the pressure line to one side and the temp sender to the other side.

So much better now. At idle I see about 2-3 PSI and at WOT about 12 PSI. Now I have a usable gauge.
Hey MB, I tried a temp gauge in the same spot, only trouble was the temp gauge I had did not start low enough (automotive gauge) so it always showed cold or 120deg F. What kind of gauge did you use?
 

Moody Blue

Captain
Joined
May 24, 2004
Messages
3,136
Re: Water pressure gauge install feedback

Temperature gauge I have is made by Beede and reads from 60-200F. Bought it off ebay.

Even with this gauge I still only see the lower end of the range while operating. These motors are really cold blooded.
 
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