Water pressure gauge for 200 Mercury

jdupree

Petty Officer 2nd Class
Joined
Aug 11, 2006
Messages
185
Want to install a water pressure gauge on my 1992 Mercury 200 to monitor water pump pressure. Has anyone done this? When you buy the gauge, does it include a fitting to tie in with? Where is the proper place to install the fitting? Thanks
 

jbwetjen

Recruit
Joined
Jun 15, 2007
Messages
2
Re: Water pressure gauge for 200 Mercury

I have a 1999 200 hp EFI bluewater. The water pressure guage is hooked to a barbed fitting in front of the shifter shaft on the lower unit. the tube comes out by the shaft and up thru the motor pivot tubea and on to the guage. you will have to remove the lower unit to install the fitting.
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,758
Re: Water pressure gauge for 200 Mercury

There should be no need to drop the lower unit. You can simply "T" into the tell tale on the engine as shown below. (Ignore the thermostat and bypass valve notations). The water pressure connection is the brass fittings. This is on Merc three cylinder but there is no reason it won't work on your engine. Chances are the instructions that come with the gauge will tell you the same thing. Mine runs about 5 PSI at idle and 15-16 PSI at WOT. I use a Teleflex gauge. Simple install and generally everything you need comes with the gauge. The brass fittings you see below were used instead of the plastic pieces in the kit. These are standard plumbing fittings available in the plumbing section at any home improvement store.

Thermostat.jpg
 

gss036

Commander
Joined
Jan 18, 2003
Messages
2,914
Re: Water pressure gauge for 200 Mercury

On the V-6 block the connection is on top center of the block, right behind the flywheel. If there is a hose coming off yours, (if not, you will need the brass 90 degree connection after removing the plug there) then Tee into it the and route your line around the side of the block and out of the way location up the guage in the dask. Telflex is the most common and has good instructions and will include everything you need or they will tell you what to buy locally. Very easy job and nothing complicated beyond connecting the hoses.
DO NOT bleed water up to the guage, it is operated by air being forced through the line from the engine. Depending on the engine the pressure read around 2 psi at idle to 12 psi @WOT. Some have been known to go as high as 22 psi.
I like what Silvertip shows using a Tee at the source instead of cutting the hose. On the V-6 blocks, don't tie into the pee-hole hose, you will not get good pressure readings.
Check E-Bay there are deals to be had there at times.
 

jebeebe

Petty Officer 1st Class
Joined
Nov 26, 2006
Messages
322
Re: Water pressure gauge for 200 Mercury

I have a 1999 200 hp EFI bluewater. The water pressure guage is hooked to a barbed fitting in front of the shifter shaft on the lower unit. the tube comes out by the shaft and up thru the motor pivot tubea and on to the guage. you will have to remove the lower unit to install the fitting.

on my 60 that barb is for the speedometor.
 

jdupree

Petty Officer 2nd Class
Joined
Aug 11, 2006
Messages
185
Re: Water pressure gauge for 200 Mercury

On the V-6 block the connection is on top center of the block, right behind the flywheel. If there is a hose coming off yours, (if not, you will need the brass 90 degree connection after removing the plug there) then Tee into it the and route your line around the side of the block and out of the way location up the guage in the dask. Telflex is the most common and has good instructions and will include everything you need or they will tell you what to buy locally. Very easy job and nothing complicated beyond connecting the hoses.
DO NOT bleed water up to the guage, it is operated by air being forced through the line from the engine. Depending on the engine the pressure read around 2 psi at idle to 12 psi @WOT. Some have been known to go as high as 22 psi.
I like what Silvertip shows using a Tee at the source instead of cutting the hose. On the V-6 blocks, don't tie into the pee-hole hose, you will not get good pressure readings.
Check E-Bay there are deals to be had there at times.[/QUOTa

Thanks for the info. I will look for the fitting at the top of the block. Just put a new water pump & impeller on. I have always owned a Johnson/Evinrude and this is my first Mercury. I am used to the nice strong pee at idle that those motors show. The mercury doesn't pee great at idle but as soon as you accelerate it pees great. I was told that the pee will not be very strong at idle because it runs thru the t-stats.

I just want to monitor the water pump to make sure it is putting out as it should. Thanks
 

gss036

Commander
Joined
Jan 18, 2003
Messages
2,914
Re: Water pressure gauge for 200 Mercury

The water pee hole description is normal for a Marccury V-6 engine.
 
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