1999 Tige Mercruiser intermittent audible beeps every 3-4 secs

Lptexastornado

Recruit
Joined
Aug 31, 2015
Messages
3
Hi, got my 1999 Tige 21v about two months ago and love it. Two Saturdays ago we were out on the river andthe serpentine belt started splitting so limped back to the dock and that was it for the day. As we slowly made our way to the dock the belt continued to fray and belt particles got all over the hoses and my engine. Last week I replaced the belt and while I was at it I replaced the impeller, oil and spark plugs. I also installed a 10" sub and 600watt amp that runs the sub. The power is being pulled from the single boat battery at the back of the boat.

Once I got the boat put back together from the sub install, impeller, plugs, oil and belt repairs we went out last Friday to test it out. I started getting a softer audible beeping warning sound. All gauges were at normal working conditions temp, oil , voltage all normal. It beeps at RPMS 2500 -3000 and beeps every 3-4 secs. Sometimes it will beep 4 or 5 times sometimes only once. I can run it WOT at 4000 - 5000 RPMS and it won't beep but when I pull it back to 2500RPMS it starts beeping once every 3 seconds for a few times then will stop. We pulled the air filter cover and the round silver air filter had that black serpentine particles all over it. I cleaned it off with a rag and the beeping went away for the rest of the day. Went home later and sprayed brake cleaner in the silver air filter and blew it with the air compressor to clean it real well.

Put the boat in the water tonight to do a final test run before our big trip to Lake Ouchita for Labor Day weekend and the boat is back to beeping at me again at the same RPMS 2500-3000. Once again the engine seems to be running crisp and will run great no audible beeps or sluggish running at idle or WOT. and even at 2500-3000 RPMS it runs fine just beeps every 3-4 seconds for different durations then sometimes stops beeping at those RPMS.

Any ideas what could be causing these beeps? We have a 4 night camp out and 3 full days on the lake and counting on the boat for 3 families and I am hoping it runs good the whole time. Any suggestions would be great. I'm going to try to get it into a mechanic to scan the engine but not sure if I will be able to find one to scan it in the next three days. I'm fairly new to boating and just got the Tige and am getting hooked fairly quickly!!!! They are way to much fun for me and my 5 yr old and 3 yr old!

Engine serial # is 0L390830

Thanks in advance for the help.
 

NHGuy

Captain
Joined
May 21, 2009
Messages
3,631
So which engine is this?
Did you try isolating out the subwoofer power supply since that's the newest thing?
Does the engine show normal gauges at the rpms that have the signal beeps? At those rpms you might simply have the nose of the boat up high. If it has a drive lubricant reservoir with level sensor, the lube might need a top off.
On my 97 Alpha 1 the serpentine belt goes pretty close to the drive reservoir, it's possible that the belt debris may have affected the wires to the reservoir sensor, take a look.
 
Last edited:

NHGuy

Captain
Joined
May 21, 2009
Messages
3,631
By the way the standard alternators in our boats aren't that big. You might want to figure out if that big amp will take too much juice and run down the battery.
You can get more charging power if you need to, just make sure it's marine rated. Car alternators aren't electrically shielded and can cause fuel vapor explosions in boats.
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Ok, engine is... 1998 MIE 350 MAG MPI SKI STD EXHAUST. (we don't really care what boat it's in, just what engine it is)....

MPI, that beeping could be quite a lot of different things, and the only way to know for sure is a scan tool or laptop with the diagnostic software....

One item that has been causing issues like this is the water pressure sensor mounted in the power steering oil cooler. And apart from a straight swap, the only way to know is ^^^^

Chris......
 

Lptexastornado

Recruit
Joined
Aug 31, 2015
Messages
3
Well I put the boat in real early this morning and disconnected the power supply for the amp at the battery and the beeping was still there.

I am going to try to see if I can get it scanned before our big trip this weekend.

All gauges read normal at the RPMS that it beeps at. I wonder if this could be a big problem that could ruin the engine if I run it on our trip this weekend without knowing why it's beeping. Engine seems to be ruining really good. Had a friend that knows a good amount about car engines out with me last Friday and he said it sounded like the engine was running real strong and smooth. This is very interesting.

Thanks for all the help
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Well I put the boat in real early this morning and disconnected the power supply for the amp at the battery and the beeping was still there.

I am going to try to see if I can get it scanned before our big trip this weekend.

All gauges read normal at the RPMS that it beeps at. I wonder if this could be a big problem that could ruin the engine if I run it on our trip this weekend without knowing why it's beeping. Engine seems to be ruining really good. Had a friend who knows a good amount about car engines out with me last Friday and he said it sounded like the engine was running real strong and smooth. This is very interesting.

Thanks for all the help

If it is the pressure sensor, then there is no harm to the engine, but without the scan, that is a pure guess.

BTW, car engine/boat engine... Poles apart. I have an uncle who is a very highly qualified diesel mechanic, also knows cars inside out. I service his boat engine.

Chris......
 

Lptexastornado

Recruit
Joined
Aug 31, 2015
Messages
3
Ya I hear you on boat and car mechanics are two different beasts. I found a mechanic that will scan it today and see if he gets a error code. I told him the work I had done and also told him I know just enough to get me into trouble, so we will see what the scan code comes back at.
 
Top