1999 225 OX66 Oil burning question

[sdudra]

I have a 1999 27ft Grady White with Twin 225 OX66 engines on the back.

This past weekend, we went out of St Augustine due east in hopes of catching the wonderful Wahoo. 205 Gallons of gas on board and 2 stroke oil tanks completely full. After a fun ride out in sporty sea conditions, we trolled for about 4 hours and decided to head in.

At the time that we headed in, we where 48 miles from the inlet and planned on stopping in 15 miles to bottom fish. We made about 7-8 miles when the oil alarm went off on my port engine. After a quick inspection of the tank, it was almost completely empty (enough to make the alarm sound). I found this VERY VERY odd since the starboard engine tank was 3/4 full. I put 2 gallons in the tank and we headed in.

What would make the engine burn through so much oil? There is no hole in the tank so that is out.

I am taking it to my local Yamaha mechanic today, but thought that my forum brothers can give me some ideas on what it might be as well.

Rodbolt, your thoughts????

I look forward to hearing everyone's replies.

 

[rodbolt]

Re: 1999 225 OX66 Oil burning question

my toughts, checking the engine tank is googly noogly as your alarm and visual indicates just told you the engine oil level is low.
however were there 3 bars flashing on the tach or a single bar?
were both REMOTE tanks about equally low?
while running much above 3500 RPM you will burn roughly 1 gallon of oil per 50 gallons of gasoline for each engines fuel burn.

 

[sdudra]

Re: 1999 225 OX66 Oil burning question

Honestly I dont remember what the indication on the Tach was Rod. Of course the engine shut down as designed. I shut everything down and looked and the tank appeared empty. The other tank was still 3/4 full. That is what baffled me!! How is 1 tank empty and the other tank ONLY 1/4 used???

There was no oil slick behind my boat that would indicate that there was something wrong. As I said, I am baffled!

 

[rodbolt]

Re: 1999 225 OX66 Oil burning question

how much fuel had that engine burned during that trip and did you verify BOTH remote oil tanks contained the same amount before leaving the dock.
and not to bust chops but dont ya thinks its kinda stupid NOT to look at the visual indicates when an alarm audible arises? if you KNOW what is going on it may save your trip, motor or LIFE.
one far left bar flashing indicates low ENGINE oil tank level, MIDDLE bar flashing indicates low REMOTE tank level all THREE bars flashing means a transfer system malfunction,oil transfer hose pinched OR a clogged remote oil tank filter. means the REMOTE tank has enough oil to transfer yet the ENGINE oil tank is low. not supposed to happen in normal operation.
so you ran at least 30 minutes with the middle bar screaming at you,BLINK;BLINK.
the blinking is the ONLY indicate of low remote tank oil level there are NO audibles for this.
however the two typical causes of excessive oil consumption on the 3.1L are either a broken clip at the oil link arm causing the oil pump to go to wide open or a leaking oil pump shaft seal and crankcase vacum,sometimes even gravity, to flood number 5 and 6 cylinders with oil.
O2 sensor WILL NOT cause this.
also be aware that quite often the link arm must be modified to obtain the correct arm to stopper claerence with the throttle shutter fully closed, fully cloesed does NOT mean at idle opening but fully closed.
DO NOT bend the arm to adjust it.

if after the correct link and sync procedure is done and the arm to stopper claerence is to great you can cut off about 5 threads from the link arm.
do it wrong and the engine WILL expire.
no tech bullitens just almost 20 years of playing with the 3.1L yamahas.

 

[sdudra]

Re: 1999 225 OX66 Oil burning question

We really had not burned that much fuel at the time this happened. If I had to remember I would be guessing to say between 40-60 gallons total. Yes I do know that the remote tanks had been completely filled because I knew that I would be going offshore and filled them up and put additional oil on board to ensure this would not be the case.

Yes you can call me out regarding the visual indications. I was not paying attention to them as I didnt see anything blinking until the alarm went off.

I know that now, the far left and far right ones blink when trying to run that engine. It is on the way to the shop now and I do have faith in the tech that is looking at it. He is well known here in Jacksonville and has a very good reputation.

I did hear from another mechanic that the linkage could have broken and that dumps oil.

I appreciate your candor rod. That is why I posted this out here. I will keep everyone updated with what jeff finds this week on it. I do believe that I will have him look at this guage also, as I think it needs replaced anyhow as the tach was a little difficult to read so I wonder if it works at all......

Thanks again!

 

[rodbolt]

Re: 1999 225 OX66 Oil burning question

a real quick easy way to test several things at once,as per the maint schedule.
drain the engine oil tank via the water trap. periodic maint.
reinstall the water trap.
make sure the remote tank is at least half full.
turn the key on and observe a few things.
audible should sound.
3 bars should blink.
transfer pump should run 180 seconds and, on the 3.1, fill the engine tank from empty to just above 1\2 full.
now in one simple stroke we have performed 4 maint actions.
we tested the audible.
we tested the tach.
we tested the transfer rate.
and we cleaned the water trap.
we now have 5 minutes involved in maint.

 

[rodbolt]

Re: 1999 225 OX66 Oil burning question

if you wish to further test the tach indicate then with the key on engine off,unplug the 4 wire connector at the REMOTE tank.
center bar will flash as the SWB,remote tank switch,just opened as far as the ECU and tach are concerned.
its one of the few,very few, signals that UNGROUNDING a device will trigger an indicate or action.
with SWB open,REMOTE tank low, automatic transfer will NOT occur but manual transfer can be done about twice.
then your out of oil for real.
for some reason precision blend kicks techs butt but its so incredibly simple its unreal.

 

[sdudra]

Re: 1999 225 OX66 Oil burning question

Rod,

The mechanic found that both oil filters on the transfer tank needed to be replaced. One oil pump was caroded and he replaced it. The oil link was broken on 1 engine and that put it at full open. As a precaution he replaced the carter keys??? on the 2nd engine on the link to ensure that this would not happen on it.

However, he did determine that I need 2 new Yamaha tachs.

PT # 6y5-8350T-81

1 tach, the oil light indicators work fine, but the Tach is faded. The other, the tach reads fine, but the green indicator (Shows tank full of oil) is not working. it stays on Yellow. I am afraid that the ECU might see this and shut the engine down.


So far, not to bad at 350 dollars (Approximate) but swallowing the full price to buy 2 guages at $500.00 is killing me!

Any help is appreciated.

Thanks,

Stephen Dudra
Stephendudra@yahoo.com

 

[rodbolt]

Re: 1999 225 OX66 Oil burning question

cotter keys have nothing to do with the clip cracking. the clip will tell you months before it breaks that its gonna.
you will see a dark line in the flat side of the clip body paralell with the link arm months before it breaks.
takes 5 minutes to change.
only 1 filter on the REMOTE tank.
notice how I keep capping ENGINE tank and REMOTE tank?
like I said before NO ALARMS for the REMOTE tank level switch other than a yellow lamp or center bar flashing for SWB. SWB is the REMOTE oil tank switch.
its closed when level is ok illuminating either the green lamp or the far right bar.
open it,low REMOTE tank level, or break a wire and the center bar or yellow lamp lights and automatic transfer CANNOT occur.
however open it between the 4 pin harness connector at the engine to the tach and the system will work but the yellow lamp remains lit.
check the green wire from the 4 pin oil alarm harness to the tach.
a quick tach check, simply switch the oil alarm leads under the console and see if the problem is now on the other tach.this can be done with key on engine off.
external pump corrosion is rather normal on twins more so with twins on a bracket, not a real cause for concern.
tachs aint cheap, make a cover for the new tachs to prevent sun damage while not in use.
I think you have a wireing issue on the tach with the yellow lamp or automatic transfer would not have occured and your run would have lasted about 30 minutes before the ENGINE tank went low and your alarm went off,hopefully.
the 3.1L ENGINE tank switch MUST be tested periodically as the centering guide in the filter assy can and will curl and not allow the float to drop far enough to trigger a low ENGINE tank alarm and actually allow you to run the engine dry on oil until it pukes a rod with no alarm.
goes back to the real quick easy test I posted.

 

[sdudra]

Re: 1999 225 OX66 Oil burning question

Rod,

I appreciate your insight. To be sure that I am explaining this correctly, I do have twin engines and twin remote tanks obviously. When I explained things to the mechanic, I thought there was an oil problem and so did he. I asked him that if he was to check one of the tanks and replace filters in both, test both the remote oil pumps and verify that both are correctly pumping oil to the tank on the side of the engine.

How he accomplished that, I am not sure of, but the one engine that I spoke of that shut down, he verified that remote tank filter was clogged and not allowing "proper flow" to the tank on the side of the engine. Once this filter was replaced, the pump pushed the oil at the correct volume to the tank on the engine.

He then went to the engine that used the most oil that day and the oil link arm had a broken clip and just as you explained previously, he did the same that it caused the oil pump to go to wide open. Since he corrected this with new clips, I asked him to do the other engine to ensure that both where new and that I would not run into this issue again.

Regarding the tachs, 1 tach is just sundamaged. all the oil indications work fine. The other tach, he thought was strange that just the yellow indicator was on, so he put another tach in temporarily to see if it was the tach, and he said that all the lights went off accordingly and worked fine.

It started to rain here in Florida, so he did not water test the boat and wanted to see if I wanted to replace them or not.

He also indicated that he will ensure that the ECU is correctly communicating with the oil pump and set correctly. I assume that this means that oil flow is adjustable?

Anyhow, it seems that he has done everything that you have indicated as well.

Thanks for all of your assistance. I wish that you where local so that I could get my boat to you.......

 

[rodbolt]

Re: 1999 225 OX66 Oil burning question

he ECU does NOT communicate with the oil pump. period.
the oil control module was incorperated into the ECU on all 3.1L motors and all V6 2.6L since 1990 and always on the HPDI 2 strokes.
oil flow rate is NOT adjustable,period.
the oil flow is determined by the angle of the throttle arm via the oil control link arm and oil pump arm AND engine RPM.
the ONLY real communication the ECU has with the oil control module is for setting the oil visual and RPM reduction, on twins if rigged correctly it also sets the other engine in RPM reduction via the DEC switch located on the key switch panal bracket.
like I said, its an incredibly simple system that can and does kick technician butt for some odd reason.
its also the most widly missed section on the masters exam.
the oil control module is looking at several things at the same time.
REMOTE tank level,is there enough for automatic transfer? switch SWB.
ENGINE tank switchs,there are 3.
sw 1 is pump off command when the float is up, switch closed,sw2 is pump on command when the switch is closed due to the float at the mid point.
sw3 is pump on,again and notify the ECU to set the audible,set the visualset RPM reduction and if equipped set the DEC control.
anytime the key is on the transfer pump brown wire has 12 positive power.
the oil control function in the ECU,based on signals from both SWB and SW2, turns the pump on by grounding the pump blue wire internally.
the manual overide switch can do this manually in the event of SWB failure,sw2 failure or sw3 failure.
once the ENGINE tank level reaches the top line SW1 closes and signals the ECU to turn off the pump. pump remains off until SW2 closes again.
this open,close cycle repeats until there isnt enough oil for automatic transfer or the key is turned off.
once SWB opens,or a wire, black or black\red breaks. the ECU inhibits automatic transfer and the yellow lamp or center bar on the tach is lit.
after SWB opens there is enough oil remaining in the REMOTE tank for approximatly 2 manual transfers.
remember keyswitch must be ON for a manual transfer.
in a previous post I explained how to test oil transfer rate.
REMOTE tank filter cleaning or inspection is a once per year OR every 100 hour inspection.
O2 sensor cleaning AND testing is once per year OR every 2 hundred hours.
ENGINE oil tank switch function and oil transfer rate is once per year OR every 100 hours.
the two can be combined at the same time as well as water trap removal and cleaning.
the ONLY time you will get a key on automatic transfer is if TWO things happen.
one is SW3 is closed,ENGINE oil tank low, AND SWB is closed,REMOTE tank level ok.
pump will turn on for 180 seconds.
other than that there is NO automatic transfer unless the engine is running and the ECU is getting pulser coil signals.
thats why Yamaha PRINTS a maint schedule for OX66 EFI 2 strokes.
if you follow it those motors stay happy a long time, dont follow it and some tech somewhere gets a new pair of shoes.