water pressure guage hookup

[racefan2]

Re: water pressure guage hookup

Will keep you all posted.

 

[Mark42]

Re: water pressure guage hookup

I get 3lbs at 900 - 1000 rpm, 12-13 psi at 5000 rpm on my Evinrude 1993 40hp. The gauge is connected to the exhaust cover where there was a factory plug, not "t" into tell tale.

I can tell you that I got different readings using the tell tale, and also got no reading when using the garden hose. Got proper readings using the trash can full of water to test.

And the length of hose you run does affect the overall pressure readings too because of the resistance caused by trying to compress the air in the line. In theory, if you had a long enough hose, nothing would come out the end.

Also, when i block off the tell tale, the PSI will jump up 1 or 2 psi at idle.

 

[Silvertip]

Re: water pressure guage hookup

Mark, it really doesn't matter what the "maximum" reading is. Unless you install a new impeller at the same time as gauge installation, you don't know what "normal" is. Whatever is "normal" regardless where its plumbed is what the object of this installation is. With a new impeller and idle and wot readings taken, any deviation from those readings indicates a problem. Also, water never reaches the gauge as its closed. Water pressure does however compress the air. Works the same way as the speedometer, just calibrated differently.

 

[Mark42]

Re: water pressure guage hookup

Yep, I agree. I just posted my numbers so he has a reference.

 

[racefan2]

Re: water pressure guage hookup

That is good reference numbers for me to look for. I installed a brass t fitting right into the block at the factory plug with the teltale comming out the straight across opening and have the pressure guage out the branch with the brance going up to keep a full flow of water. It made no difference in readings on muffs with branch up or down.

What gets me is when I first hook up the gauge and install hose I get 2 lbs at idle then it drops to 0 and then on it stays at 0. I have installed this guage hose 3 times and it happens every time for the first 10 seconds or more then it drops to 0 go figure:^

My readings at 4500 RPM are on the water running the boat. On muffs no high RPM for me and I cannot use a trash can unlesss I remove my SE200 hydrofoil.

 

[racefan2]

Re: water pressure guage hookup

I got the new gauge today and installed it. It worked great at first 3 lbs at idle then after about 1 minute if started fluxuating a bit then it started dropping and stopped at 0 again and that is where it sits at idle. It does move faster at RPM as I was at 5 lbs to 6 lbs at 2000 RPM for the short period it was at that RPM. I did as mentioned above and hooked it up to the block directly and got no different readings.

This is my rigging as it sits the top ot the T is the pressure guage hookup and the straigh run is the teltale.

This is the teltale pressure at idle 0 pressure reading

 

[Silvertip]

Re: water pressure guage hookup

Have you replaced the impeller yet? Place your finger in the water stream and slowly bring it closer to the tell tale outlet while watching the gauge. The close off the tell tale. If the gauge does still does not read, I'm thinking you are in need of a water pump. At least you'll know that part of the system is ok. I'm also wondering if you should have a 0-15# gauge.

 

[racefan2]

Re: water pressure guage hookup

I have not yet made the change of the water pump. I have located one for 45.00 but they want 150.00 to install it so I will have to do it my self for the first time so I have to wait as my fishing buddy is in town for 2 weeks of fishing as he drove 18 hours to get here for these two weeks so rather that take a chance I will just hold off till he leaves.

I have blocked off the teltale and even done better as I run the pressure directly to the block and got no change in pressure at all.

a 0 to 15 lb gauge would work but I think I would still get the same readings though.

How hard is it to change the waterpump? I have looked at my service manual and it don't look hard but it does not tell you how to disconnect the shifter rod. to lower the lower unit.

 

[ricksrster]

Re: water pressure guage hookup

Water pumps are easy. Do you have a manual?

 

[racefan2]

Re: water pressure guage hookup

Yes I have a service manual. I shows most steps except removing the shift lever arm which I think needs removed from the top end of the motor.

 

[Silvertip]

Re: water pressure guage hookup

Look where it comes up from the lower unit just below the carb. Not sure on that model, some have a plate on the side of the lower unit. Remove the plate and the coupling is under it. Otherwise its disconnected at the linkage below the carb. Don't forget the bolt under the trim tab.

 

[racefan2]

Re: water pressure guage hookup

Silvertip thank you for the information.

 

[Mark42]

Re: water pressure guage hookup

so whats the latest?

 

[racefan2]

Re: water pressure guage hookup

I just got home from my week long fishing trip. While I was out I picked up my new water pump assembly. I went for the whole thing not just the impeller to make sure I have all new. I went for the factory OMC unit. I just have to get a bit of free time to tear it down and install it as I have never done it and want to make sure I have time and am not rushed.

While out it stayed the same 0 psi at idle 7 psi at speed

 

[racefan2]

Re: water pressure guage hookup

I have pulled the lower unit to install the new water pump. I found right off the water tube housing on the water pump was cracked. It is under the rubber seal but it was still cracked and the impeller and cup looked fairly new no cuts or marks. The tube itself when I tried to blow through seemed a bit stuffed so I set it down and then my father came by and blew in it and sait it went right through so there was maybe something sucked in there and he did not see it come out.

I installed a new water pump and had two rubber seals left and found they were for the spacer on top of the pump that connects the pump to the midsection. It was not there and so I have to try to locate one in stock now before I can finish the job :'(

I used a tire pump to blow air both ways through the system and it flowed both ways would like to do water but not sure how to get water into the small hoses.

The gauge did more but not as much as I though it should. If I used the air directly in the hose for the gauge it jumped fine.

 

[racefan2]

Re: water pressure guage hookup

UPDATE
I cannot get the part locally so I have to order it. I found it at Ishopmarine. Anybody ever place a order from them?

 

[rickdb1boat]

Re: water pressure guage hookup

Yes, I did. Not a real good experience, but there was some miscommunication. Be very exact when you order. I would call them and place the order...And make sure they do have it in stock...

 

[Mark42]

Re: water pressure guage hookup

When I installed the gauge in my boat, I though it a good idea to blow through the line to be sure it was clear before connecting to the gauge.

Man, that is tough to blow through. I mean seriously tough. 16 feet of small diameter hose does not move a lot of air easily. In fact it felt at first like nothing was going through. But after a minute or so I realized air was moving, just not as fast as I expected.

I don't think the water moves very far through the tube, maybe a few feet at max pressure.

The gauge works well and consistantly.

Good luck.

 

[racefan2]

Re: water pressure guage hookup

I put new water pump in and have good water pressure 10 lbs at quick hit to 2000 rpm

Here is my solution to the water pressure issue.

http://forums.iboats.com/bbBoard.cgi?a=viewthread;fid=1;gtid=1141983

 

[Silvertip]

Re: water pressure guage hookup

Very nice indeed. However -- I think there might have been one or two more inexpensive fixes to the water pressure issue. d