225 promax low water pressure at idle

[allisonjr]

I have an 2000 225 promax that has recently acquired a problem with low water pressure at idle. Its reading like 1 or 2lbs instead of 5 or 6lbs of pressure. Ive changed my impeller, removed my thermostats and flushed the heads with fresh water. Cleaned the line that goes to the water pressure gauge. I need help with suggestions with what I may have as an problem the motor runs fine other than this issue. I checked compression and all is equal across the board. Any help would be appreciated, the only thing I haven't messed with is the poppet valve.

 

[silverbullet02]

I'd check the poppet valve then. Could be something stuck in there holding it partially open.

 

[njj502]

Ditto

 

[allisonjr]

I've never messed with the poppet valve before is that real complicated or pretty straight forward?

 

[xb03]

Straight foward! Mine will only idle as high as 6psi on a hose, 2psi in the river/lake.

 

[chad202]

Unless you have a problem with overheating, run it. Mine would always be around 3ish.

 

[Allyfishing]

I've never messed with the poppet valve before is that real complicated or pretty straight forward?

If you've never removed/disassembled/installed the poppet before I suggest you take it to a certified merc mech. And that is not saying that you are not skilled or able to do it.

I am no mechanic and had mine apart on my ProMax because my water pressure was giving me fits. I had it apart more times than I care to remember and it finally came down to me noticing the large black plastic washer where the screw went thru that holds it together being ever so slightly warped or actually "cupped". And that was not until after I had an entire kit with every single piece new laid out in front of me for the final attempt.

Now, are you and the wife coming to the rally?? We missed you guys at the dinner last year? Where did ya get to?

 

[mdevrow]

Sportmaster LU check the Side Plates,Water channels for Trash!! From the intake to the water pump can get slightly/or completey stopped up with wood or foreign material. Then I would check the water pump and water pump housing it self for problems.

 

[njj502]

Unless you have a problem with overheating, run it. Mine would always be around 3ish.

He had higher pressure and now it's lost 1/2 of it at idle. Run it would not be a good idea in this situation.....

The poppit is very straightforward if you are mechanically minded. Just be sure to be VERY careful when you put it back in so that you don't stick it open.

 

[njj502]

Here is a diagram of the poppit.






27 & 28 are in the block. Make sure poppet is in there square. Also be sure all the parts are there...... Hope this helps.

 

[allisonjr]

Guys thanks so much for the help i havent ever taken the side plates off my sportmaster. I'm going to try that first i hope its stopped up there cuz that would be an easy fix. Craig my wife and i are trying to make it to the rally we had lots of fun last year. We had drove in that friday and just was being lazy that night. i wish now that we had gone to the dinner because everyone we met at the rally was super nice.This water pressure thing is driving me nuts i hope i get the problem nailed down soon

 

[chad202]

Guess I'm different. I run temp gauges on my engines. Losing 2lbs at idle is not a big deal if mybtemps are normal and could have you chasing ghost. Been there, done that. Have you applied a set, known pressure to your gauge to see if just maybe it went off? You mentioned you changed the impeller. The impeller only? When you start your motor, does it start peeing instantly?

 

[allisonjr]

I changed the impeller and the top two gaskets on the impeller housing. The water is not peeing right away even if I raise the Rpms. And I have not checked the gauge to a set pressure

 

[bec]

guess i'm different. I run temp gauges on my engines. Losing 2lbs at idle is not a big deal if mybtemps are normal and could have you chasing ghost. Been there, done that. Have you applied a set, known pressure to your gauge to see if just maybe it went off? You mentioned you changed the impeller. The impeller only? When you start your motor, does it start peeing instantly?

me too found trash in the tube going to gauge.

 

[ROBERT CROSS]

Had the same low pressure at idle last year when I sucked seaweed.
Had to clean the stat's and popet valve and flush.
Got a P-valve kit in the tool box now just in case.

Also found a torn WP gasket.
Found out the hard way they need to be Permatex'd to the stainless plate.:confused

Bob
:very happy

 

[njj502]

I like to use 3M Trim Adhesive for tacking the gaskets down. It gives it a tacky surface to stick to but isn't thick like gasket maker... Just my $0.02.....

Where did you get a "poppet kit" Bob?

 

[ROBERT CROSS]

I like to use 3M Trim Adhesive for tacking the gaskets down. It gives it a tacky surface to stick to but isn't thick like gasket maker... Just my $0.02.....

Where did you get a "poppet kit" Bob?

Ahhh yes..better known in this area as "elephant snot"




Got the kit at Boats.net...

Merc# 803062t-1, was the kit for our 2004 225xPM.

Bob

 

[allisonjr]

Well just pulled the side plates off the gear case and it was crystal clear

 

[whipper]

Guess I'm different. I run temp gauges on my engines. Losing 2lbs at idle is not a big deal if mybtemps are normal and could have you chasing ghost. Been there, done that. Have you applied a set, known pressure to your gauge to see if just maybe it went off? You mentioned you changed the impeller. The impeller only? When you start your motor, does it start peeing instantly?

agree with Chad on this. If your temps arent high its not going to pee much. I would be more concerned if my temps went way up than what my water pressure is at idle. does the pressure go up when running? If so dont worry about it so much it at that low of rpm it will be hard even for the water pressure gadge to register. Temps tell the real story.

Temps below 140 at idle and lower when runnung above 50 good to go as far as im concerned. Do you have a real low idle? like 650 or less? Does it pee or does the pressure rise on plain? does it over heat buzzers ect at idle? If your sucking air because the gasket even has a hair line split in it it will heat up at idle. Also not all impellers are created equal. if your realling woried about it the cheepest thing to do is install a another impeller and dont tighten the steel screws to tight on the plastic housing:] Oh ya and dont run it on the hose. It only takes a sec to burn out an impeller if not submerged. i ussually take 3 or so impellers and feel them all and size them for hight and width. i pick the biggest one and stiffest one:] Yes im still talking impellers. i just find the quality control isnt like it used to be.

 

[silverbullet02]

The question is why did it change? It ran one way and now it's different. Something happened. I had the same issue at the beginning of the year but an impeller fixed mine.