adding "water pump indicator"

**outboardjetboater** · 08-01-2007

i recently purchased a 72 omc 3 cylinder. it starts and runs (after new starting solenoid), but i can not find water pump indicator. does it have one, if not can one be added? fairly able to perform work, but wanted to get information first. thanks

jetboater

**Bill Gohr** · 08-02-2007

72's didn't have an indicator. You can add one if you want, pick a spot up high on the block and drill the water jacket, use the little plastic fitting used on later engines in the pan so you have the correct size whole in the end. It is a restriction.

**outboardjetboater** · 08-02-2007

should i be worried about metal chips in the water jacket after i drill and tap hole? may need to think on this a bit!

thanks again bill

**Bill Gohr** · 08-02-2007

now some of the 72's would have what looks like a flat head screw in the water passage up high on the ignition side which is a plug going directly into the water jacket. You could use that if it has it. I wouldn't worry about the small amount of chips that will get into the water they will go out the prop. It is important to use the plastic piece on the pan though, it is a restriction so you don't bleed off too much water pressure.

**mercmack** · 08-02-2007

Get Some Hard Grease And Fill The Flooks Of The Drill Bit With It, Before You Drill..it Will Keep Most Of The Bits On The Drill Bit..
Just An Idea

**JohnsonM50** · 08-02-2007

Originally Posted by mercmack

Get Some Hard Grease And Fill The Flooks Of The Drill Bit With It, Before You Drill..it Will Keep Most Of The Bits On The Drill Bit..
Just An Idea

That does work well plus use a sharp bit and let the drill speed do the cutting so when it punches thru the last bit of debris will mostly be drawn out. Do the same to the thread tap. When you choose the orifice size youll find that when your allowing too much water out the head will heat up and the exhaust jacket will be cooler, an OMC rat Ive got I experimented on and set it so the exhaust is a little hotter than the head by feel, this has worked well for a long time. You could if you want, run the hose forward and exit the stream outward where you can see it from the driver seat

**outboardjetboater** · 08-03-2007

hey bill,

could not find any screw on the ignitions side, unless under a coil or something. i took a pic, maybe you could direct me in the right spot.

jetboater

**Bill Gohr** · 08-03-2007

On the 68 thru 71 engines there was a boss on that side with a plug in it, it was going to be used for something else and never was. Your block may or may not have it. I don't remember when it went away. If you drill a hole anywhere in the block behind the thermostat you'll be OK, Do it up on top of the block, the higher the better it will just act as an air vent on start up, as well as the highest point is the first point to lose water pressure. There is a flat area on the block just inside the exhaust covers that would be fine.

**mercmack** · 08-03-2007

I Am Using Omc Gages In My Application..just Like There Looks..and I Got Them Both Gages (temp And Pressure) Off Of E-bay And Saved A Group ..they Work And Look Like New...