Hi guys, bare with me please. This is my first post and my first o/b. It's a 1988 200 black max, I replaced the impeller because I was getting no psi on the gauge and just a mist from the tale tell. Now I'm getting 12-15 @ idle on the muffs. Is this pressure good? Also I have not had it in the water so no WOT readings yet, as I want to make sure everything is up to par before hand. Thanks
Anybody have an idea if 12-15 @ idle is too high or am I being overly skeptic.
Welcome to BBC! You shouldn't have near that much pressure at idle.. 2-4 psi is normal 12-15 is minimum for wide open throttle..Are you sure your gauge is accurate? Does it zero out with motor shut off?
I just purchased the boat so I am not certain of anything but it does zero out. Could I have installed something wrong when I replaced the impeller to cause such a drastic spike?
<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by Kris365 »</td></tr><tr><td class="quote">I just purchased the boat so I am not certain of anything but it does zero out. Could I have installed something wrong when I replaced the impeller to cause such a drastic spike?</td></tr></table>
Please specify EXACTLY what parts/part numbers you installed.
This is critical information...
I will tell you that some of the later water pumps are MUCH more efficient at low RPM's (as compared to the older housings)... and in some cases, you may see SUBSTANTIALLY higher water pressure at idle on a fresh pump install.
This usually tames down into the "expected" range after a couple of trips to the lake.
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 48 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
I'm not sure of part numbers right now but it was a water pump repair kit from NAPA(no marine supply near me) that was cross refrenced to my serial number. I only replaced the impeller, paper gasket, metal gasket, paper gasket, rubber "slinger" and pick up tube. Sorry if these are not the correct terms for parts.
Also when I installed the impeller I had to bend the "arms" so it would go in the housing assy and some cupped a different direction than others. I was told after it ran they would fix themselves. Probably should have put that in my first post but is that correct?
Thanks for your patience and help with a newbie guys!
We don't recommend "aftermarket" water pump components... so in that respect, you "have what you have".
ALL impeller blades MUST be folded for CLOCKWISE SHAFT ROTATION during assembly. Improperly folded impeller blades seldom "fix themselves".
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 48 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
Ok thanks! I'll pull the pump and check the blades and report back. Also I'm wanting to replace the gauges, are there specific gauges you recommend?
Post or email a picture of your dash.
Sherm @ Sherm's Marine (or I) will be happy to set you up with a Mercury/Quicksilver Water Presure Gauge that's a suitable (close) match.
Email or Phone are the BEST means of contacting the Parts Department(s).
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 48 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
Ok I pulled the LU and pump assy to check the impeller I just installed. Blades were all in correct position, but psi gauge still reading 10 to 12 @ idle.
Also I ran into another problem, when I buttoned the LU back up and got her on the muffs I checked foward and reverse gear as I've read a ton of threads on gear issues after pump replacement. As my luck would have it, it would not go into either forward or reverse. I dropped LU again(for the 3 time) to check and see what happened and the female "gear arm" would not center inside due to the housing it is in would not let it. I used a stainless rod through the holes in the transom mount and trimmed down, that allowed me the clearance to get the female gear selecter arm centered over the male spline in the LU. Is this a normal occurance on older motors?
Sorry for the super long post and the butchering of the terms and components. Thanks for all your help.
You must manually manipulate the upper shift shaft (a small access slot is provided where you can grab it) while installing the gearcase. This is NORMAL.
You should, however, be able to engage both Forward and Reverse after PROPER reassembly.
If you've completely reassembled, and still have 10-12 psi at idle, that MAY be due to increased efficiency of pump components you installed.
We sometimes see this with the OEM kits as well... on the OEM kits, pressures usually tame down into the "normal" range after a couple trips to the water.
You will have to use your own, best-judgement, however.
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 48 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
Thanks for all of the helpMaintained normal temp, gauge pressure still a little high but hopefully as you stated the it will "settle". Thanks again!
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