No beep when trying to start ??? Won't start
 

Yesterday after running boat with no issues,came back to boat. Boat started fine and idled for 5 min or so then sounded almost as it was missing and died. When turning the key numerous times noticed there was no beep when turning the key and would not start....after checking fuses breakers and trying to continually start the beep came back but engine would start up and die right away...then let it sit for a few minutes then starts up with now problem for the rest of the day... it is a 502 mag motor please help

do the gauges come up when there is no beep, turning key to run position?

You know I believe so...

Sure sounds like a bad (shorted) battery or bad battery cable connections. 3rd poss would be the remote start/ign solenoid.

So..start with basics !

How to test start solenoid?

do have teathers?

cannon Plug ?

I was going to check cannon plug today for sure

Teathers??? I don't know what that is

kill switch ie: lanyard is the ref to teathers from above inwhich the kill switch could be a problem / issue as well. Thats easy to test.

You need to post year and engine serial number of your engine and is a totally stock application

Pins within the cannon plug - 2 simple tests for that. Possible the cannon plug problem ??? Kind of sounds like it to me ??? Have a volt meter in hand as well for testing all your 12V sources

Loose starter cable ??? had that plenty of times

Loose engine back side ground(s) had that plenty of times - even had stud(s) broken off that work and 2 seconds later nothing just from slight movement of the boat.

Yes I'll check the kill switch teather ,and I'll start checking ground straps and wires....what I thought was odd was that warning beep went away then all the sudden came back? Should I not worry about that?

Sounds like what I posted to me and again have your volt meter with you for testing all 12 v sources and any relays

Sounds like the lanyard - try pushing in the red button to see if the alarm sounds, mine does the very same ! Why I'm taking my boat to BUP for a few things!

BUP- hopefully this week if my schedule permits !

^^^^ thanks but look at are weather this whole week to come. WE are going to get hammered as they say. I am sitting around as some getting their boats today to put back in storage so they do not get hammered. Jeez hope this is not like last year with rain.

You are right - lets waits for this to pass then I'll drag her to you ! Sorry to hi-jack op !

Hate to even mention this again, but besides the no beep issue, that sounds an awful lot like vapor lock that I have experienced a few times.

If it was a vapor lock issue how would you correct it? Why would it start and idle for 5 min or so then stumble and die

As bup asked earlier, what year is the boat? Have you owened it long, a little history would help.

As BUP stated you will need to get 12volt references and ability to check those that require the source.

A simple alligator clip jumper from a know battery source (battery is best) to +side of coil to stabilize the ignition.. It could answer some questions if your lanyard or other issue is the root.

LIke others have said. Could be tether or bad kill switch. There is also a hot wire that triggers that buzzer. If it lost power it will not start either. Mine is loose... I redid my dash panel and tried cranking the other day and after pulling the key panel and sticking my hand in the dash.. After moving some wires, buzzer came back on and she cranked right up.

Good luck, I hate freakin elec gremlins!

29 scarab 1998 single 502 with bravo drive

1998 should have GEN II cool fuel system NO VST system.

Now you say it starts and runs for a tad then stalls ???

If that is the case I would check fuel flow and fuel pressures.

Fuel flow can be checked with clear fuel line for testing ONLY.

You should have a spin on fuel water sep filter as well. Have you changed it ???

Engine serial number dictates what you have for parts and systems. Year model of the hull means not too much for the engine and drive side.

Isn't the beep for the fire boy system arming? I have found at times the wiring to the fire extinguisher rots out and can cause a no start issue. Also check to see if you have a anti siphon valve in the fuel line anywhere as they can plug up.

it has only done it this one time ?? after about 15 min. I got it restarted and it was like it never happened? I haven't changed the water fuel separator since I bought it only owned it for 4 months or so https://webmail.kirbycorp.com/OWA/at...0160307_155451

Most of us took this as the starter wouldn't crank when you turned the key.

Are you saying that it did crank, but engine wouldn't fire and run ?

This can be totally different avenue of diagnostics from each other.

after having a fresh set of eyes went back over to storage and tried to duplicate the no beep when starting.... and I did I found by cycling the key faster then every 4 seconds or so the beep would no beep. so at this point in more concerned with the no start issue. I think I created the no beep issue by cycling the key over and over real fast. im starting to really lean towards a vapor lock issue has anyone else had similar issues serial number to engine is 0f884374??

after doing more research believe mine has the vst fuel vs. the cool fuel however can someone post a pic so that im sure? seeing how it only has done this once sure seems like a vapor lock issue or a fuel issue im changing fuel separator today and continue to dig more info on making sure the vapor lock symptom's are stopped ? am I going in the right direction? checked cannon plug oil pressure switch battery connections ect. no white milky stuff in cap as described above... I think the may be the issue

Cough, cough, ....ahem. Please answer this.

I take it as no start=rurrurrurrururur
no crank .............
Ray, I'll try and post up a pic of my setup later today, but maybe with your serial number Bup can say definitively what system you have.
Still more info would help, been boating all winter in the south? Or first run of the season after layup. If you give these guys GOOD information they can really help you out.

I'M NOT A MECHANIC- so take this with a grain of salt

I had something a little like this when I first got the boat - the warning beep would go on/off for no reason -- turned out it was how I set the depth warning -- nothing was wrong. Believe me I looked everywhere, oil level, grounding wires etc. DUGH

3pointstar

Would start for less then a sec then die

Totally different motor but I had a Corroded Fuse that caused that. Find the fuse that controls that and wiggle it with the key on next time it does it.

Chris

Ray this.is an original version vst.[ATTACH=CONFIG]552193[/ATTACH]

Well, I figured out why I had no beep (would crank but not fire off).

Ended up being a loose spade connector on the S kill switch. I pulled dash off and traced wire from kill switch and still didn't beep. So I took key panel off again and started playing with connections behind kill switch. AND there it was. I recrimped the connectors and she's good!

I typed too soon on mine. It started working better, but still not a strong buzzer. So I cut and stripped and replaced all the connections behind both switches and kill switches.
NOW, I figured it out!! The D$mn switch!!!! Worked some times and works perfect others. Only found it bc I was playing with the key when it didn't buz and then it buzzed while playing with key.

POST # 26 the engine serial provided by OP has the VST fuel system. the engine is listed as 1996.

At first he reported a 1998 engine as in 1998 there was no VST fuel system for those year models. Hope this helps whomever. IMO might be best someone refer you to a Mercruiser trained mechanic and or shop with a trusted name. No offense to you. Good luck

Just for confirmation purposes! Yes you are correct with your engine model, if you cycle the key to quickly the audio warning horn circuit will not have a chance to reset itself within the MEFI ECM thus not sounding the horn with each key up without allowing roughly 10 seconds of rest in-between key-ups. My personal 1996 454 mag MPI is the same way plus I have noticed it multiple times in the past on many different boats of that era.

If it is vapor lock, then try doing a search either here on OSO in the upper right hand corner of each sub-forum page (or google online) for vapor lock Mercuiser 454/502 Mag MPI as there's lot's of info for this issue. One trick of many is sending the fuel return line back to the fuel tank vs back to the water separating fuel filter adapter housing from OEM stock.

Hope this helps, good luck.:)