Not sure if water psi sender in this tstat housing will show block psi, as it had pretty good size bypass to the exhaust in it.

I’d move sender to block drain hole, unless some verifies in this tstat housing is okay.

My MPI’s used the same style housing and that’s where I had my water pressure tap.

You mentioned not having a bypass… why is that? The pump needs it for circulation during warm-up. If the temp drops below the opening point of the thermostat, it could stop water flow creating hot spots and all kinds of associated problems. If the manifold doesn’t have a provision for a hose barb, drill two 3/16 holes in the thermostats so that water can flow properly.

That tstat housing has a large bypass back to the recirc pump. The tstat is over it, (reason for plastic collar tstat sits on) no need fir drilling holes in tstat.Do not need hose from recirc pump to intake.

Okay, thanks for info.

Didn’t know that about the thermostat housing.

:) Yeah, in due time. Will prob be replaced instead of paint. That's just how I roll.

Today was a good day.

Managed to run WOT for a bit with 6 adults in the boat. Oil pressure stayed slightly above 40 psi at 5 k RPM. Maybe I was slightly over filled? And armed with knowing other HP 500's only make 40 psi I felt pretty safe running it like that for a short blast across the lake.

Didn't pay attention to the water pressure gauge, was busy looking for boat wake as we were closing in on some other boats.

I need to address the temp sender and see if I can get it installed without using a thread adapter of some sort. Trapped air pocket might be my issue with that one.

Thanks for the compliments, compared to what you guys have, my stuff looks REALLY old.

If the thread adaptor is brass try drilling the inner pocket to give temp probe good access to liquid. Be very careful installing into block as the brass will be thin and be susceptible to breaking. Also no Teflon or pipe sealer. Good luck

It is brass and pretty cheap. So if i mess it up, no problem. Thanks for the tip

You said you have new gauges.......Is the oil psi sender the right ohm for the gauge??

Water Temp.......What temp T stat is is in it??? Someone could have installed a 120*. Stock HP500 carb is a 140*

Water pressure.......No way you only have 3-4-5 psi at cruise. If you did you'd overheat. I get my water pressure readings from the same location. Not sure why you used that big of hose. All you need is 1/8 poly tubing. My guess is you've got a kink somewhere.

I was referring to the PIA to remove from intake if you break it by over tightening it.