Water pressure install - Mercury ProMax 150 ss

**aeneas** · 05-28-2019, 01:00 AM

A couple of months ago I bought a Merc PM 150 ss and I am now re-rigging the boat (steering, instruments, controls etc). Where do I hook-up for accurate readings?

**tux974** · 05-28-2019, 05:05 AM

The exhaust plate is where I run the water pressure fitting. See small hole between voltage reg's.
See picture below. Its an 1/8" pipe thread/fitting.

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I also sleeve it with a thin hose to protect from heat near head and block and route it close with a 90* so it does not get damaged with cowling.

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**Dave Strong** · 05-28-2019, 01:45 PM

What Tux said.

Dave

**aeneas** · 05-28-2019, 04:56 PM

Excellent! Thank you!

Here is my powerhead... Looks like a brass bolt in that hole.

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Nice pair by the way!

**tux974** · 05-29-2019, 04:47 AM

Originally Posted by aeneas

Excellent! Thank you!

Here is my powerhead... Looks like a brass bolt in that hole.

Nice pair by the way!

Yes, that should be an 1/8" thread pipe plug unless someone touched it, hard to tell.
I would suggest the 90* brass elbow you can purchase at your local hardware store then fitting if you can not locate a 90* fitting.
I use a 90* swivel push lock fitting from my local hydraulic shop.

**aeneas** · 06-17-2019, 12:10 AM

Originally Posted by tux974

Yes, that should be an 1/8" thread pipe plug unless someone touched it, hard to tell.
I would suggest the 90* brass elbow you can purchase at your local hardware store then fitting if you can not locate a 90* fitting.
I use a 90* swivel push lock fitting from my local hydraulic shop.

I followed your advice to the letter.