1994 115HP bubbleback alarm.

[Fishjustin87]

Has good compression and spark. Already dealt with a overheat alarm via thermostats and pump. 1st test run the other day and and seemed to be missing one cylinder. Idled rough but planned out great. After an hour of up and down in speed it sounded an alarm. Shut it down immediately and gave it a few. Tried to start and it only cranked. Next day cold started and ran really rough and then died. Would not start. Comp good
spark good. Pulled bowl plugs and pumped some fuel through and it fired great on all 4. Thought fuel restriction alarm. Put in water and started great. Let idle and ran up 3 min To help wife bring the kids down and was sounding no oil beeps. Shut down and checked each head temp. Only 95 F. Would not start. Tried flipping fuel solenoid and still nothing. Have not gotten to try again cold. Suspect carbs need rebuilt but why no oil alarm. Vro? Once alarm triggered can it shut down spark?. Plan to build carbs but am concerned about Vro. Side note. Tach does not work. Any help would be greatly appreciated

 

[Joe Reeves]

It would be best if you described the exact alarm you're hearing. With no intention of insulting your intelligence, we have no way of knowing if you know what a no oil warning is or which one you're referring to if you do (Low oil at tank... no oil at vro). However I assume you're speaking of a horn alarm that beeps every other second (VRO failure).

If so... and applying pressure to the oil tank bulb causes the alarm to cease... BUT... the alarm comes back into effect again within a short time... that indicates a VRO failure.

Your statement of pumping the fuel primer bulb causing the engine to start (not in so many words but to that effect), that sounds like a complete VRO failure. Rebuild or replace it.

 

[Fishjustin87]

Yes no oil meaning beep every other second. One thing I notice is the oil ball is rock solid. The thing puzzling me is that it would not start once I shut it down. The first time is sounded I turned it off so quickly i was unsure what tone it made. The second was every other second. As I understand it the oil level switch is in the tank that triggers a low oil level via beep every 30 seconds and the no oil alarm is monitored by a sensor in the VRO itself if it does not detect oil flow in the mix chamber. Can a backed up carb cause this alarm. I think if it was not getting oil head temp at idle still would have been hotter than 95 degrees after 4 or 5 minutes. Still would not start even after re squeezing the ball and manually forcing fuel into the carbs. I understand that it could be related to bad fuel pump side of the VRO. Is there a quick test I can do to test. After the first time i pulled one of the 2 fuel lines coming from the fuel solenoid and verified while cranking it appeared to have a good flow. I have limited tools at the moment but am looking at what kind of tests I can run to verify the fuel pump is pumping and the oil is moving. At this time it is probably going to be put on the back burner because I have a kid coming beginning of October and Archery season opens in a few weeks but was hoping to be able to at least diagnose prior to the off season so I could go straight to work once the weather has turned. I really appreciate your response.

 

[Joe Reeves]

Yes, you are correct in your thinking knowledge of the oil tank alarm and the VRO alarm. Why the engine wouldn't re-start once you shut it down... I wouldn't know without troubleshooting it. However head temperature of 95 degrees would have no effect as the thermostats do not open until they're somewhere around 143 or so, meaning head temperature is normally much higher than 95 degrees.

Failure to start could be related to fuel (or oil) flowing thru a faulty VRO directly into the crankcase (flooding).... flooding due to a primer solenoid being activated too long, strange things happen via Murphy's Law.

Simplest test of the oil side of the VRO is as I mentioned.... apply pressure to the oil primer bulb... if the alarm ceases, then returns after a short time, that's normally a indication of a failed VRO. Yes, it could be air in the oil line OR a oil restriction, BUT if the oil line was originally primed properly (no air) and oil flows normally when the primer bulb is pressed... that leaves the VRO, unless a piston has blown that affects the function of the VRO... and that I'm sure you would know about.

********************
(VRO Horn Warnings)
(J. Reeves)

NOTE: I retired around 1991/92. Possibly some of the later V4 engines and others may also incorporate a fuel vacuum switch that would enable a fuel restriction warning to sound as mentioned below, an unknown factor to myself.

1 - A steady constant beep = Overheating - The V/6 engines, possibly some others, have a fuel restriction warning which is also a steady constant beep.

2 - A beep every 20 or 40 seconds = oil level has dropped to 1/4 tank. (Late model engine = Every 40 seconds)

3 - A beep every other second = VRO failure, air leak in oil line, oil restriction, (anything that would result in a lack of oil being supplied to the engine).

NOTE - If the warning horn is the black plastic (overpriced) three wire type horn, the warning horn should beep once when the ignition key is turned to the ON position. If it does not, it is either faulty or someone has disconnected it (a stupid move!). At any rate, if it does not beep which indicates that the horn is non functional, find out why and do not run the engine until the problem is corrected.

********************

 

[Fishjustin87]

Thanks

 

[Tassie 1]

Also you say " compression is good "
what are the actual numbers?

 

[Fishjustin87]

111,116,117,117 after the 1st test run and alarm. Have not had time to see if it will fore again. Also noticed after the first time when I pulled the plugs 3 of the 4 plugs were wet. Figured the carbs were not letting fuel to the 4th. After pulling carb bowls it and pumping fuel through them and repluggingit fired great and hit good on all 4. Showed some poppiness. Thinking also a carb issue but I know it could be the fuel side of pump too

 

[Fishjustin87]

I also thought of something else I just thought of. I also just changed the oil in the reservoir. Could I have an air lock in the VRO?