Low Water Pressure ?
 

I just posted this in the (Drives / Lower Units) section but thought maybe it might be a Baja related problem. Just looking for a fix so I can run my boat in rough water.

I have a 05 33 Outlaw with 496 HO's (70 hrs on engines). It has been in the shop numerous times for the starboard engine going into guardian mode when running in rough water trimmed out some and at speeds above 60 mph. The problem never occurs as long as I am running in smooth water. It is not the rev limitor. This last time Marine Max of Clear Lake, Texas said they had finally found problem ( water pressure sensor). Same problem again a week later while running in rough water. Back to the shop again. They put it in the water again yesterday and made numerous passes in smooth water and found no problems (had lap top plugged in to collect data). They then had to make only one pass in rough water for alarm and guardian mode to cut in. They say low pressure points appeared on readout. The water pressure sensor had been replaced the week before as they thought that was the problem. Now they want to change out the impeller. There has never been an overheating problem. Any ideas or suggestions before I go and replace something else that might or might not correct this problem

They need to check for a restriction in the water flow path. Since there is a sensor, does it tell you what the actual water pressure is or just that it is dropping below a certain threshold.

check for air geting into the system I would bet your seapump housing is scored its brass , once this happens it will cavitate and heat up there is a rebiult kit 165.00 if your marina changed a sensor before checking the the seapump i would ask for the old sensor its still good, your impellor will look ok but its not kit come with everything you need 412781-0881Bob

The engine has never ran hot. I can idle around Clear Lake all day and never see a temp. increase. I ran it this past weekend on the San Jacinto river and never had a problem. If I get out in the bay and there is some chop it's going to to go in alarm. Per the tech. at Marine Max, he also thinks it's picking up air from the outdrive and causing a low pressure spike.

+1

I change the housing and impeller every season and no issues. If it has not been changed with 70 hours that is what your problem it. These boats are built to air out and I have never heard of that being a problem.

Good luck

We need to talk!! I have a 2004 30 Outlaw with 496's and I have had the same problem over the past few years. It ONLY does it on my port engine when I do poker runs (high speeds in really rough water/prop wash). The rest of the time, throught the entire season the boat is fine, WOT, kinda rough, runs fine. It's only in poker run settings/lot of boats where this happens. It's very incidental. I replaced both impellors (did not replace housings but they looked ok). It had 140hrs, they were not worn a bit. After that, boat ran great all summer, until 1,000 islands, then did it again. After that, I tried swapped sensors, boat ran great until this weekend at our run, did it again, still port engine.

I have been told three different things:

1) I'm getting too much air and there is nothing I can do, stop going fast in poker runs.
2) The brass housing needs to be replaced as this actually wears and can cause airation (I would think it would do it all the time if this was the case, and on both engines)
3) X-dim is too high and I should plug a couple of holes on the side of the gear case to prevent airation when leaving the water.

Please give me a call as I would like to trouble shoot this.
Joe (518) 774-4067

Doc, these are 496's we are talking about, very specific issue as they have a sensor right on the sea water pump that is way too sensitive, and causing these issues.

I had a issue similiar. My water pressure was high though. I have a smartcraft to view H20 pressure though. My port engine would go into guardian mode as well. My issue was the oil cooler was plugged. I pulled the right hose off the exchanger(when looking at it from the front) and then the rear most hose off the oil cooler and flushed backed wiggeling my finger in the oil cooler. Lots of seaweed etc came out.

I have replaced both my water sensors....expensive little buggers 100.00 a piece. You would think maybe a 20.00 sensor.

Before I cleaned the coolers I did change both impellors. Both were still in good shpae and kept them as emergency spares.

Just another ave to look at.

If I didnt mention. This happened when running WOT and trimmed out is when guardian mode would kick in .
Temp guages never over heated but my water restiction was always there.
The restriction was after the guage so it displayed high water pressure. 30 PSI vs about 20 at WOT.

I chased this problem for two years , If you can feel the scores in the brass pump It needs a re biuld kit the impeller cavitates creats air pocket in the heat exchanger and the only way to get rid of it is to stop shut down then primes up system by starting engine . If your seapump is perfect, look for loose hose clamps somewhere airs getting in check fresh water flush on the Bajas they use plastic 90 behind hose bib and it loosens up check heat exchanger if theres one tube blocked that will cause these symtoms also heat exchanger gaskets only last about 100hrs if they are sucked in this could let air in also I really noticed this when I put cmi exhaust on the boat I would see white smoke /steam after hard run You guys could have more than one of these issues at once ,for instance if the air is getting in before sea pump it will wipe out the pump,cause those little scores I mentioned even if the impeller looks good its not feel free to call or call R&R industries In lake havasu

your issues seam to be from resriction after it was cleaned out it should of went away correct

If it was X dimention problem this would happend to both engines shrink wrap tape the holes on the side of your outdrive aslong as you have low water pick up also and go out in in the chop and see if it go,s away The sea pump doesnt cavitate until higher rpms

Thats for the info guys. Going to pull pump to see what it looks like.

I'm going to try plugging a few holes on the drive. It definatly only happens when I air the boat out. I can run WOT forever and it's fine. It's so incidential, very rough, washing machine like water/high speeds that this happens.
If I had a blockage or scorn pump I would think it would be much more consistant at WOT. I was told that Baja lowered the X on 2005 and later 30 Outlaws. That makes me wonder as well, as mine is an 04.

I understand and frankly I have never heard of this problem before.

If you look at Fountains and other stepped bottom vee hull with very hig "X" dimensions you would expect to be seeing a lot more of this problem.

I'm still with Bobby here in that if the pump is not doing it's job the water is running back when you air the boat out. So you are seeing more of a pressure feed to the engine when running rather than the pump actually pumping and pulling the water up into the drive.

I learned the hard way with my new setup that you CANNOT have any air getting into the system or it will kill you water pressure.

Please keep me posted on what you figure out.

I would bet money that his systems venting somewhere and his seapumps shot if he dont find the air leak he will ruin a new pump been there done that ,when you put the new pump on it seems ok at first the air bubbles score the pump melt the sides of the impeller and its real apperent when running hard not at normal use I have 3 seapumps and about 6 used impellers ,impellers look perfect when you look real close you can see the are melted on the ends

UPDATE:

I did not try plugging holes in drive. I did inspect heat exchanger, backflushed all lines, no blockage. Inspected t-connection and entire fresh water flush system, no leaks, check valve perfect.
Had new sea water pump installed. Old one did have very minor wear marks, impellor had no signs of damage.
After running the boat hard, I could not get the alarm to go off. Now the starboard alarm did go off. Great news as this never happened before, it was always the port, thought the pump was the issue.
Well, now I'm bummed again, just returned from 1,000 islands and the port low water pressue alarm with the new pump installed ended up going off again. Back to the dealer for some more computer scans, but I'm stumped as both engines now have done it.
Again, it only happened when I was airing the boat out. I ran close to WOT most the weekend and things were fine, unless I caught some air or was in really washy/choppy/boat wake water.

take the new pump apart drag your finger nail across the housing if its scorn already your sucking air before the pump the air can wipe out a pump in a few hours of running make sure all hose clamps from transom to sea pump are tight ,also fresh water flush cap is tight and the 90 behind this cap is tight if it drips it is also sucking air

The original pump housing did not having scoring at all. The impellor looked fine. The end plates did however have some minor gouges. Now, all the clamps on the fresh water flush and drive intake hose were and are tight as well as the 90 elbow and black cap on the flush. Since the other engine did it I'm just stumped. That pump was a ***** for the tech at the dealer to remove/install. This Merc dealer is a great facality and a friend. They take their time and it's done right. I don't know if I can put him through it again:eek: He suggested bypassing flush all together for now and see if that helps. I would think if the t-connection or any other part of the flush was leaking air, it would do it more often. Bottom line is I'm sucking air and I really think it's from the side holes on the gear casing. Boat air's out, air sucks in, alarm goes off. The question is, what to try next?

I wish Callaway would chime in and let me know what he found out with his. It sounds very similar to my situation.

Thanks for advice Crayola. I really do appreciate it. :drink:

Check the T-fitting into the flush system for the fresh water hose hookup. These are known to get filled with silt/sand/crap and restrict water flow at times. I've even seen them installed backwards which is really bad. Stupid thing to go wrong, and last thing you would check, but this will do it. Also, make sure the cap on the end of the fitting where you attach the garden hose is making a tight air tight seal with a good rubber washer.

I posted above that the T-fitting/clamps/cap/washer are all in perfect working order. Thanks for the suggestion though.