Yanmar engine alarm when trying to start

[lcline27]

Hi all,

When trying to start the Yanmar 47 port engine on our cat the alarm would sound necessitating turning the battery switch off then on again to get it to quit. Sometimes it would take up to ten times to start the engine or sometimes the engine would start right away. Several mechanics in the Caribbean looked at it and after a new starting battery, alternator, the final verdict was hydrolock and we had to have the port engine rebuilt. Two weeks later it is doing it again. Did we just spend $$$$$ for nothing?

Thanks for your help,

Richard

[VanIslandGuy]

Did you check the contacts on the engine battery switch itself? We had a similar issue. Cycling the battery switch as a short term fix tells me the issue would be in the switch and not the engine.

[SwellGuy]

Originally Posted by lcline27

Did we just spend $$$$$ for nothing?

Sounds like you spent $$$$$ learning an important lesson: know the problem you are fixing before you fix it.

Hope you had more reason to suspect hydrolock than observations made at the control panel. That's like buying a new car because the check engine light came on.

Is your wiring up to snuff? "Click, nothing, click, nothing, click, there she goes!" has *always* been marginal wiring contacts for me. Starter motors draw an awful lot of current and marginal contacts will work fine for small loads but give you problems with a massive load like a starter.

[a64pilot]

Very first thing I would do, right now is confirm or deny hydro lock, that is something that is very time sensitive.
If you do the screwdriver trick on the starter and it spins over, it’s not hydrolocked.
Hitting a starter on a hydrolocked motor isn’t a good idea, but if your system is in good shape you have been doing that already.

Best is to pull the injectors and spin the motor if no water comes out of the injector holes, you weren’t hydrolocked, if it does, you need of get oil in there pronto and get any water out, run the motor, change oil until it’s no longer milky.
Then you have saved you motor and you can go about figuring out why and how it’s getting hydrolocked.

[SwellGuy]

Originally Posted by a64pilot

Very first thing I would do, right now is confirm or deny hydro lock, that is something that is very time sensitive.
If you do the screwdriver trick on the starter and it spins over, it’s not hydrolocked.
Hitting a starter on a hydrolocked motor isn’t a good idea, but if your system is in good shape you have been doing that already.

Best is to pull the injectors and spin the motor if no water comes out of the injector holes, you weren’t hydrolocked, if it does, you need of get oil in there pronto and get any water out, run the motor, change oil until it’s no longer milky.
Then you have saved you motor and you can go about figuring out why and how it’s getting hydrolocked.

Oh good point - it could be hydrolocked again. Ooof.

[RaymondR]

The alarm is supposed to sound when you turn on the ignition and will stop after the engine starts and the oil pressure pump establishes the running oil pressure. If it does not sound when you switch it on it indicates that the oil pressure warning system is not working correctly.

[Wotname]

Exactly what model Yanmar do you have?
Exactly what alarm was being activated (what idiot light was on when alarm sounded)?
AFAIK, there is no alarm for a hydrolock (apart from a broken engine ).

Very important points have already been raised above, especially a64pilot (post #4), SwellGuy (post #3) and RaymondR (post #6).

Find out exactly what is wrong before trying to fix it - shotgunning repairs are expensive and not always effective!

[GordMay]

Greetings and welcome aboard the CF, Richard.