Have you back flushed the engine with lower unit removed? Could be a blockage that might be pushed out this way.
Have you back flushed the engine with lower unit removed? Could be a blockage that might be pushed out this way.
Also pull thermostat covers and run and see if you're getting good water flow to thermostat.
I did just do a static flush on Saturday, but did not know to do so with the lower unit removed. I'll definitely try that. I assume to test water flow to the thermostats you just do the static flush with those covers off, and make sure water comes out? I guess I don't know what I'm looking for, i.e. how much water pressure should there be to the thermostats? I actually just got new thermostats today and finsihed putting them in not 5 min ago. The old ones looked pretty good, but since it's cheap to try I figured "why not".
If you made a 11 mile run at 70 MPH that's wot. No way you have a water pressure issue. I have NEMA gauge display on my Lowrance Live unit and find it's inaccurate..just me on that. My Ranger water pressure gauge is mechanical and displays 20-25 at wot. In the end a engine cannot run wot for 11 miles with poor or no water pressure, if it does it's going to be fried I would think. I would think the ECU would shut down the engine with high temp also. I hope you find something that clears the issue. I think it's not wp at this point. Good luck and keep posted.
RangerZ - IONIC Batteries, Lithiumhub.com
Thanks everyone for the help. I'm gonna try that static flush with the lower unit removed, and will be back on the water to test Saturday. Hopefully this is a non issue. I'll keep monitoring engine temp and take it from there.
Originally Posted by RangerZ
I totally agree with RangerZ....There was a thread here a year or so ago where "Tracer1" was having trouble getting any water pressure readings off his SHO. You may want to send him a pm to see if he resolved it???
2002 Skeeter ZX200
2018 200SHO
One other thing to check if you have the LU off is to be sure the grommet in top of pump housing (where the water tube goes in) is still there. It creates a seal to be sure all water actually goes up the tube...
2002 Skeeter ZX200
2018 200SHO
Well shit. I just replaced the entire water pump kit, including the pump housing. I don't remember seeing any grommet on the tube, and one did not come with the pump housing or complete pump kit. Time to search for a part number.
I think it's called a Damper Water Seal maybe?? It's inside the plastic housing where the water tube goes in but I don't think it can fall out easily unless last person to change impellor had it out. Also there may be a seal on the tube itself but I can't remember. Anyway these are just a couple things to check while you have the LU off...
2002 Skeeter ZX200
2018 200SHO
Certainly that could be the issue, that grommet tube seal is there for a definite reason. If it was not replaced with the prior impeller replacement, it could not even be there now. Good reason to study the repair manual before taking on the project. Hope that is the fix. Still wondering how a 70 MPH run for 11 miles could be. That tube not being installed would definitely reduce water pressure, but may have allowed just enough to get by. Good luck, keep us posted.
RangerZ - IONIC Batteries, Lithiumhub.com
Your new housing may not have come with the seal/retainer included so maybe you were supposed to move them from your old housing? I'm just guessing...
This is the seal...from SIMS Yamaha
6E5-44365-01-00 DAMPER, WATER SEAL 1 $9.53
This is the plastic retainer that holds it in.
6E5-44312-00-00 COVER, WATER PUMP HOUSING $2.61
2002 Skeeter ZX200
2018 200SHO
Well, that has been a long time ago for that post. I have to agree with McQuaig and RangerZ on the 11 mile run. I would say the problem is in you lower unit. Every grommet and seal should be replaced and sure that they are properly installed. Unless you are very very knowledgeable on Yamaha lower unit, find someone that is. These lower units are not like Mercurys. They seem to be a little more finicky. I went through mine twice completely and thorughly with a Yamaha mechanic manual. Don't overlook the thermostats either. I changed everything in mine that would be water pressure related. I now have around 7 psi at idle and 17 psi at 5000 rpms.. 21-22 over 5500. I very seldom and really can't remember when I last ran at wot. Don't fish tournaments any more and don't have the need for speed anymore. My power head was changed out in 2014 from a Yamaha recall although it ran fine. I now have around 900 hours on the ecu and 550 on the powerhead now. Mine starts, idles, runs, (and looks) like new. I don't understand the 11 mile run part though. Somethings not right with that picture. Maybe a bad reading on NEMA or a bad WP sensor. Recheck your LU, thermostats, and wp sensor. Let us know any updates. BTW, YAM911 is veery knowledgeable on the motors. Seems to be the "Don Weed" on Yamaha motors.
i pulled the lower unit this morning. Sure as the day is long those two parts were not there. I had the old housing sitting in a heap, and verified those parts were not there either. I verified part numbers on SIM yamaha via diagrams, and a local shop had them in stock, and I just put them in. I'll test the boat tomorrow or saturday and see where the pressure is. Thanks so much all for all the help. This community is pretty amazing.
hey Brian...hope that's it...good luck
2002 Skeeter ZX200
2018 200SHO
Yes, my SHO runs 18-22 psi on plane by the digital gauge on my Lowrance.
Butch Derickson
2011 Z521 w/250 hp SHO
Traverse City, Michigan
I tested the boat today with those parts now properly installed in the impeller housing. Results are interesting. This change made an improvement by about 3psi. Before, at idle the NEMA gauge was registering 0.00 to sometimes 0.4 ish. But usually flat 0.00. Now at idle it's 1.7 to 1.9. Before at WOT< the highest I ever saw was 7psi, but even that was rare. More often it would hover around 5.5 to 5.7psi. now I'm seeing between 7 and 9psi at WOT, 8 ish most of the time. And during accelleration, the pressure is increasing faster than it was before without question, and the telltale looks like it has a stronger stream than before. So having the grommets properly installed improved by a few psi, but it's still not at spec IF the NEMA gauge is correct. Next trip out I'm going to pull the NEMA gauge and reinstall the manual one and see what it reads. It fascinates me that the prior owner was running the engine for god-knows-how-long without those two parts installed (and so have I since getting the boat last fall).
Also make sure your pressure line is reading from the correct place. Pic attached shows proper place for SHO (rear, bottom of block). Nema should be the same location I think. I have seen one T'd into the pee tube line and that definitely will not give a good reading....
water pressure.JPG
2002 Skeeter ZX200
2018 200SHO
Yep. I installed the NMEA sensor myself. I had what was on the right in your photo. I removed the brass colored hose adapter, screwed in the sensor housing, and hooked up the "WW" pigtail to it, following several youtube install videos.
There is an easy way to test your exhaust housing for corrosion/burn through. Drop your lower unit, take an old garden hose and cut the male end off, then push the cut off rubber end over the water tube in your upper housing. Hook up the female end to a water source and turn the water on. Water will come out of the ports around the exhaust housing, but none should come out of the exhaust housing (the exhaust housing is the large port in the middle of the upper housing). There are a few videos on Youtube that will show you how to do it.
2004 Stratos 285 Pro XL / Yamaha VF150
Thanks Mike. I did find a couple videos as you said. I'll give that a try.
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