OMC throttle buzzing when key is turned

[Pinetar]

So, I've actually dealt with this before.  Almost certainly this is an error with your automatic oil pump.  That alarm is to alert you that either your fluid level is low or that your pump isnt working, or maybe in your case it is telling you that the sender that says that you pump is working... isn't working.  My buddy had a late 80s GT150 johnson with the same issue.  We ripped the auto oiler off following some directions online and were able to turn off the alarm and then just premix gas from that point onward.

To each their own, but this is the alarm that was designed to tell you that your oil pump isn't working (so you dont fry your engine).

  I think your VRO is suspect.   That's an expensive alarm to ignore.

Best advise yet from skillet and luvmystang67. Those older Johnsons are known for faulty VRO's. By pass the VRO, mix your fuel and they should run for ever.

[luvmystang67]

Those VROs were supposed to deliver the "perfect" mixture at any throttle setting, but I think sometimes current thought would say that it is too lean and not great for your engine.  The old evinrudes sometimes even advised 100:1, but advice from the mechanic community is to run no leaner than 50:1 on all old two strokes.

I'd look up instructions to disconnect the VRO and the alarm, mix your own fuel at 50:1, and ride off into the sunset knowing that your motor isn't subject to 30 year old electronic technology. 

[Henrydog]

I worked at a marina for years.  Our best outboard mechanic always told me heavy on the 50:1 a little too much oil just shortens plug life by a couple of hours.

[Ellensburg]

Thanks for all the help.

Just an update.

Got the boat running today and played around with it.

Getting plenty of oil.

Changed out lower gear oil (need to have my seals re-done this year)



- When I jiggle the key i could get the buzzing to stop.

- Ended up taking out the omc alarm horn all together. I can replace it for about 60 bucks if I want to.

- We determined that the buzzer was just faulty and as long as I keep my oil reservoir full, I'll never have a use for it anyways.

[luvmystang67]

This is where you're wrong. If the VRO pump quits you'll never know until your engine seizes. It's not just there for funzies.  Your first warning that your VRO has quit will be one final loud clunk as your motor freezes. This is a little like removing fire alarms in your house because they go off too often.


Sent from Tapatalk, which is a mediocre app at best.

[Badhabit]

A .25 cent plastic gear in the vro system strips in the pump and you'll never know what hit your motor. Back in the day when I was having OMC powerheads reworked and lots of  power added. Not one came back with a VRO. Instructions were to pre mix 50:1. After that I never had to rebuild another powerhead.

[Ellensburg]

I appreciate the honesty. Sounds like I should order the replacement piece and put it in. Hopefully the new one doesnt buzz

[Pinetar]

I appreciate the honesty. Sounds like I should order the replacement piece and put it in. Hopefully the new one doesnt buzz

Good idea, either that or get rid of the VRO and mix your fuel 50 to 1. Easy to do and a lot safer! Those VRO's are known to fail

[BigGoonTuna]

Most of the time that the VRO pumps fail, the diaphragm falls apart and you get excessive oil in the mix.  Most of the failures blamed on the VRO pump are lean seizures or due to overheating.  Easier for a mediocre mechanic to point the finger at the oil pump than actually identify the real problem.

That said, i would not use one without the warning buzzer.  It'll tell you if you are overheating (steady buzz), low on oil (slow beep) or no oil delivery (fast beep).  I test mine once a year, just hook up a tank of 50:1 mix and clamp the oil line with vise grips, then start the motor.  It'll start chirping soon after.