2003 125 Saltwater, Alarm above 3000RPM

[fpdiver]

I can run forever at 3000 RPM but after a few minutes at 3600 RPM I get a continuous alarm. Even quicker when I run up to 4500 RPM. Need to go back to idle for 10 seconds to get the alarm to stop. Boat is peeing and it is warm but not hot. Had everything replaced at end of last season...T-stats, pump, sensor, etc.

Had a "similar" problem last year when we bought test drove the boat but that was low oil (Every time we angled up we got the continuous oil alarm).

This problem sounds like a weak water pump (brand new, dealer installed) or an overly sensitive T-stat...

Boat runs great even when alarm goes off...

THINK I AM ON THE RIGHT TRACK???

thanks

 

[Alvarez]

Re: 2003 125 Saltwater, Alarm above 3000RPM

Do you see the water pressure stronger from the pee hole over 3000rmp.If so impeller is working good.At higher rpm's you have more water flow and pressure.If it's peeing but with no pressure impeller is no good.But what I see is that under 3000rmp it does not sound the alarm.Over heating is usually caused at lower rpm's on a load faster than at high rpm's.The alarm goes off for one or 2 reasons 1st is water temperature and 2nd oil low on the resorvoir.But keep in mind even the cap loose on tank resorvoir causes the alarm to go off.Check both tanks the one on the engine and the one you fill up the oil.Lets start from there because there needs to be a certain oil pressure to build up in the system.A lose cap causes low oil pressure .The oil pressure system consists of check valves lines and pump..

 

[fpdiver]

Re: 2003 125 Saltwater, Alarm above 3000RPM

This one only has the one large tank on the motor to fill up and it is FULL (2" down"). As for the cap being tight I don't think that can be it as there is an always open air bleed on the back of the tank. I will check the pee strength vs RPM soon.

thanks

 

[fpdiver]

Re: 2003 125 Saltwater, Alarm above 3000RPM

I am posting to my own to provide an update.

1.) my searches have found a lot of people having a similar problem. Only one person followed up their posts with their solution....which was to reduce prop pitch. (after all changes to the cooling system had no impact)

2.) Shop took the boat out today and ran it hard and couldn't repeat the problem. Makes we suspect even more that the 4 people we had on the boat, with the 21P prop, may have something to do with it. One person on the boat=no overheat. Four people=overheat above 3000RPM.

3.) All aspects of the cooling system seem to be running fine according to the shop.

4.) Going to try to repeat the problem and change the prop. (21" is a little too high for our loading anyway. This should reduce lugging which will help life). Will put in water pressure sensor in the fall.

 

[Alvarez]

Re: 2003 125 Saltwater, Alarm above 3000RPM

Something doesn't sound right here.Shop saids it doesn't have an overheating problem and it overheats with 4 people on board and with one person no overheating.If the cooling system is okay then an overheating shouldn't occur with more weight on the boat.Now I would make sure is really overheating with a temperature gun or manual temp guage.Did it run fine before without the alarm with the same prop you have now?

 

[fpdiver]

Re: 2003 125 Saltwater, Alarm above 3000RPM

Ran fine all last year but we had some issue getting to full RPM. 21" prop is a bit high for that boat with a full load I think. Then we had the everything in the water system replaced since it was all original. (poppit, t-stat, impellar). I am thinking about putting in a pressure gauge but not sure if I cut into the pee line or the flush line.

Going to try to take it out again sat. if the rain holds off.

thanks

 

[fasassvalk]

Re: 2003 125 Saltwater, Alarm above 3000RPM

What size boat is it ?
I have 2000 125 Hp with a 17 pitch it is on a 18 ft 1400 pound boat and runs out 5250 rpm @ 42 mph. loaded and comes out of the hole strong.
Like the previous post said check water pressure at tell tale at the 3600 and see if it is a mere stream of water or if pressure increases at higher rpm (which it should) mine is really whizzing at 4000 rpm

 

[CharlieB]

Re: 2003 125 Saltwater, Alarm above 3000RPM

The water pressure gauge is always a good idea.

Getting back to your prop, What is WOT RPM by ourself or with only one other person and no overheating?

It is entirely possible that a 21 pitch is too much for your load and causes overheating at larger throttle settings. More throttle = More Load.

My 115 has two props, one for one or two people, and another much lower pitch for four or more people. I get the best of both worlds and am able to keep WOT RPM in the 5500 - 5800 range without any worry of lugging the motor.

I purposely didn't list my pitch as boat weight, drive gearing, make too much difference, but YOUR 21" pitch CAN be correct for light loads, depending on what your tach is showing.

Repost your WOT RPM lightly loaded, where you are able to run without heating.

THEN we can discuss prop vs rpm issues.

 

[fpdiver]

Re: 2003 125 Saltwater, Alarm above 3000RPM

2003 Trophy 1903. Dealer said he got it to reach 5200 RPM with 1 person (in the bay). We couldn't get above 4800 RPM with 4 people in 2' waves.
Also, where should I put the tee for the pressure sensor...spot 1 or 2? (see thumb nail) I tried posting this part before but no one answered. I can come off the pee line or out of the fresh water flush line.

THANKS!

 

[CharlieB]

Re: 2003 125 Saltwater, Alarm above 3000RPM

I suspect you may have two issues, timing may be off AND your prop may be just a couple of inches too much for 4 persons and gear.

Ignition timing off either retarded OR advanced and the engine will fail to run up to rated RPM.

Leave the engine cover (and 2 of those passengers) on the dock and check timing at max RPM you are able to run without overheating, adjust as required to correct, if necessary.

Retest WOT

If the motor pulls up to rated RPM range without overheating and 2 persons aboard then you need to consider how you intend to operate the craft the MAJORITY of the time, adjust/replace prop with one pitched for that load.