VST - Too Much Oil

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TnTrls

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Since I've only touched on this in another thread I thought it might be good to seperate them.

I understand that the Electric Oil Pump is controlled by the ECU. It puts simple drops of oil into my VST. What I need to know is what would cause it to put TOO MUCH oil in it. My dealer says that the pump is bad and wants me to buy a pump.

We recently disconnected the line from the pump to the vst. Of course no issues but is that the proper way to check this problem. They did this per thier conversation with someone at Yamaha!

Now...per Rod on my other thread...I know this can be monitored by a laptop or a multimeter. I dont have the laptop of course so what would I be looking for on the meter?
 
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rodbolt

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Re: VST - Too Much Oil

about 12V acrossed the pump pins when the pump is on.
remember at low speeds the pump is off.
thats why I am thinking your dealer is a pokin an a hopen.
little pump doesnt flow much, you cab test it by key on engine off take the blue pump wire to ground and observe the VST end for flow.
if debris is holding the pump open its possible to gravity feed the VST, the check valve prevents any drain back and will stop a gravity feed.
to check for gravity feed with engine tank full simply remove the line from the VST and see if oil is dripping.
but that engine will run on a 50/1 premix and the pump only puts in like 1500/1.
had a guy do it.
funny story and I may post it but now I gotta get back to worky worky.
 
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TnTrls

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Re: VST - Too Much Oil

Thanks man...you've been a huge help with all this. Just wish you lived here in Chattanooga..:D

I'm going to run these test and then carry it back my dealer with notes from all of it along with what I think they need to do. I know it wont carry much weight but maybe it will help. The closest Master Tech we have in our area is in Atlanta. A dealer that just ordered a trailer from us too. IF I have too..I'll deliver the unit myself and haul my boat behind it. ;)

Thank You!
 
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rodbolt

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Re: VST - Too Much Oil

remember,with the engine tank full, that little check valve between the VST and the electric pump does two things. one it prevents gravity from flowing oil to the tank and two as the engine tank lowers it prevents gravity from draining the line when the pump cycles off.
same as the 6 inline check valves from the engine pump.
they prevent gravity from filling the cylinders with oil while its sitting and they prevent the lines from draining or intake pulses from forcing oil back to the pump.
its also why you NEVER NEVER EVER remove the engine tank screen assy without FIRST draining the engine oil tank.
ALWAYS replace the screen assy seal AFTER retriveing the old seal.
its also why remote tank filter maint is critical.
most oil related failures,baring lack of maint, on 92 and up mikuni pump v4 and v6 2 strokes I can find a bad inline check valve due to debris in the valve.
incredibly simple system that fails more up and coming master techs than about anything else.
 
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TnTrls

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Re: VST - Too Much Oil

Lets throw somethng else into this one....

Remember, the electric oil pump is disconnected per Yamaha....Well, I took it to the lake yesterday and guess what, Nothing but smoke and sputter. The engine would not run. And this is a new powerhead too!

I pulled the VST screw and it had grit in it. They have never changed that filer, ONLY the one coming OFF the VST.

After the last go round, when the pump WAS connected, I watched them spray something into the tank from that screw area to flush all the oil out. Wonder if it ate something up in there!

Man, Im pissed! 7 months down...5 was for neck surgery recovery and this power head dosent even have 10 hours on it!
 
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rodbolt

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Re: VST - Too Much Oil

was the fuel system properly set up for storage before it was laid up 7 months?
wont matter if it had 1/2 hour on it.
grit,trash or any other debris is not normaly a yamaha warrenty issue.
NO one I ever spoke to with Yamaha motor corp ever would tell me to dissconect any oil related stuff and run it.
to simple to troubleshoot.
maybe dissconeccted cause a tech is pokin an a hopin.
if you have grit in the VST its time to change spark plugs, replace all filters,flush all fuel lines clean the VST and pump filter and change the medium pressure inline then monitor both rail pressures to insure its maintaining about 1100 PSI on the high pressure rail. that or probably pop another piston.
 
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TnTrls

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Re: VST - Too Much Oil

ARG...got back back this week and runs great. Of course the oil tank vent hose is in the RIGHT spot now!!!

Boat runs great and it did for the 2 months I was breaking it in (Nov- Dec 2009) Then it went off to upper nashville for a month or so for some fiberglass warranty work. Thats when the problems began.

Its all fixed now and I'm back to catchin Bass and slaying Crappie.

Thanks for your time here Rod. BTW...Remote oil tank sensor was bad too. My dealer hooked me up with a new tank with harness for around 200. Im good to go now.
 
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99yam40

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Re: VST - Too Much Oil

Where was the vent hose hooked to before that caused all the problems?
Was there any problems with the check valves?
why did he replace the tank,and harness if it was just a float switch problem?

TnTrls said:
Of course the oil tank vent hose is in the RIGHT spot now!!!


Remote oil tank sensor was bad too. My dealer hooked me up with a new tank with harness for around 200.
Click to expand...
 
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TnTrls

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Re: VST - Too Much Oil

We think someone fooled with my engine when it went up for the FB repairs. My batteries were dead as can be too along with a missing cull beam and scales. Who knows...Not sure about the check valves. The vent hose was connected to the intake cover when the engine og t a new powerhead..it was connected somewhere that had to do with the VST. All I know is..it runs right now.

The filter needed changed on the tank also and I did request that they change out the harness just in case. Totally new tank and harness for that price..Im cool with it and my mind is at ease.
 
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rodbolt

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Re: VST - Too Much Oil

makes all the aggrevation worthwhile, and a smile.
bet ya didnt even think of it when the bite was on :)
 
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TnTrls

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Re: VST - Too Much Oil

rodbolt said:
makes all the aggrevation worthwhile, and a smile.
bet ya didnt even think of it when the bite was on :)
Click to expand...

Sure didnt. I do when I first drop it in the water but when it starts and idles smooth...I'm good to go.

Its 6 am here in Tn and we're about to see if we can load the boat with more Crappie. :D
 
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rodbolt

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Re: VST - Too Much Oil

jeez
talk about waking the poor critters up.
good luck.
 
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