VRO Oil Alarm

rxiuser

Cadet
Joined
Sep 9, 2003
Messages
11
Recently at 3/4 throttle (~4000 rpms), i had my VRO alram go off - beef every other second - and it would throttle down my engne to about 500 rpm's. I had the spark advancer repaired and that seem to solve the problem. I have run it several times since then with no problem.<br /><br />Sunday, I took my family out and the same thing happened at about half throttle.<br /><br />Any ideas what may be causing this?<br /><br />Thanks,<br /><br />Dave.
 

ob

Admiral
Joined
Aug 16, 2002
Messages
6,992
Re: VRO Oil Alarm

Inspect the VRO oil line from tank to pump and insure there are no air leaks.The s.l.o.w. is designed to limit rpms in the event of overheat.The rapid short tone indicates a "no oil " alarm from VRO sensor.
 

rxiuser

Cadet
Joined
Sep 9, 2003
Messages
11
Re: VRO Oil Alarm

The s.l.o.w. only occurs after the warning horn goes off. I am assuming they are related. Is that true? And if so, would an oil restriction cause an overheat even if the water pump is working well?<br /><br />Thanks.
 

ob

Admiral
Joined
Aug 16, 2002
Messages
6,992
Re: VRO Oil Alarm

lack of lubrication can most definately cause an overheat.The no oil alarm by design does not initiate the s.l.o.w.Have you verified oil usage from VRO tank after running engine?What do the sparkplugs look like after the engine falls?They should be slightly oil damp.Also need to insure that the engine is not overheating by using a thermo melt stik of 163 degree or a thermo gun.A touch check of engine block and head covers ,is better than nothing.
 

rxiuser

Cadet
Joined
Sep 9, 2003
Messages
11
Re: VRO Oil Alarm

that makes sense..<br /><br />I checked the line and it seemed good. The bulb is firm and there does not seem to ba any oil at any of the connections.<br /><br />Disconnected the line at the engine cover and checked oil flow. Seems good.<br /><br />I think I need to check oil pickup from the tank and the engine temp when running.<br /><br />Did you say it should be around 163 degrees?<br /><br />Does that sound like the correct steps?<br /><br />Thanks.
 

rickdb1boat

Supreme Mariner
Joined
Jan 23, 2002
Messages
11,195
Re: VRO Oil Alarm

David<br /><br />If I might jump in for a moment. OB gives very good advice, so heed anything he points out. Your plan sounds good. 163 Melt stick is correct. Do yourself a favor until you find out what's going on. Pre-Mix your oil in the fuel tank, ALONG with the VRO at 50:1. Good insurance until you're sure the VRO is working properly. This would be similar to breaking in a new motor. Better than having it blow on you because of an unknown problem with the VRO system. Mark the VRO oil tank and verify that it's using oil before discontinuing the pre-mix. The pick-up in the tank would be a good place to check next. Good Luck,
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: VRO Oil Alarm

how old is the pump?. the advice to premix while trouble shooting is right on.<br />if the pump is a 3 wire then chunk it. I tell my customers that 8 years is the max for a rubber diaphram pump. after that they are on borrowed time. and check the pick up filter as well . good luck and keep us posted
 

rxiuser

Cadet
Joined
Sep 9, 2003
Messages
11
Re: VRO Oil Alarm

I followed your suggestions. I mixed the oil, disconnected the VRO and I am still getting the SLOW mode. I noticed that when I got it, that one head is hotter than the other. I can keep my hand on the one head for about 13-15 secs. while the other I can only keep it on for 3-4 secs. It is much hotter.<br /><br />The water pump is pissing water well and seems to be a good temp. Any suggestions why one head would run hotter than the other?<br /><br />Thanks.
 

ob

Admiral
Joined
Aug 16, 2002
Messages
6,992
Re: VRO Oil Alarm

David ,assuming that your engine is a V-4 or a V-6 ,you will have a thermstat for each bank.First thing I would do is remove the old and install new thermostats as the hotter banks thermostat may be stuck closed.Post the year and HP of the engine in question.
 

rxiuser

Cadet
Joined
Sep 9, 2003
Messages
11
Re: VRO Oil Alarm

it's a 1989 175hp (v-6). Can a non-mechanic replace a thermostat?<br /><br />Thanks.
 

ob

Admiral
Joined
Aug 16, 2002
Messages
6,992
Re: VRO Oil Alarm

Sure.However if you are not familiar with location and some of the detailed finer points that a person of mechanical background would take for granted,a service manual would be a valuable asset.Good luck.
 

clanton

Rear Admiral
Joined
Jul 9, 2001
Messages
4,876
Re: VRO Oil Alarm

The only sensors that set S.L.O.W. are the two temp sensors, unless the blocking diode in the engine wiring harness is open. The VRO, remote oil tank, fuel restriction sensors donot set S.L.O.W.
 

rxiuser

Cadet
Joined
Sep 9, 2003
Messages
11
Re: VRO Oil Alarm

Thanks for all the help so far. I checked the thermostats and 1 was wide open. Hit the nail right on the head.<br /><br />Since we had the engine partially open, we decided to check one of the heads. We thought maybe one of the rubber stoppers might be compressed and blocking the water flow. We found abrasions and some aluminum scrapings on two of the cylinders in the one head. We have not looked at the other one yet. I was told that this happens because the rings are bad. I was told to replace all the pistons and chug along.<br /><br />Is this good advice? What is the risk of just keeping the current pistons and using it the way it is?<br /><br />Thanks.
 
Top