Guy is Broken Down in Arlington, VA and has a question.

[Gary Hatt - Publisher BCM]

I was sent this from Eric Lindgren who has an MC-9 8V71, broken down at the Exxon in Arlington, VA.  Can anyone give him any ideas?  Here is his request.

I'm broke down on the side of the road, (8v71) it keeps saying low oil, but the pressure is off the charts. 

He said he was able to limp it in with zero throttle to the parking lot.

He will monitor the Forum, but is not officially a member yet, he is waiting for approval from Phil who is out of town this week.

Does anyone have any idea what could be causing this and what he should check? 

[plyonsMC9]

Also received this from Eric as well:

To: Phil Lyons <phil@busconversionmagazine.com>
Subject: Re: Bus conversions BBS Join Request

My 1980 MC-9 with a 8v71 is broke down on the highway with a low oil light. The oil is fine, it was just changed.

I plan on dropping the pan, and checking the pick-up for debris. I already deleted the oil to the alternator/generator. No leaks, current level reads full... I don't know what else it could be

[thomasinnv]

There should be two oil pressure senders on the oil manifold left side of the engine, probably mounted on top of the engine rail. One is to the pressure gauge, other one is a 3psi switch that activates the low pressure light and engine shut down. Sounds like a bad switch if you have good oil pressure. Unplug the wire to the 3psi switch and that should eliminate the light and shutdown. If he has good oil pressure there is absolutely no reason to drop the pan.

[luvrbus]

He should have a manual gage on the engine rail drivers side if reading oil pressure there disconnect the Kysor sending unit   

[Erik L.]

It seems to be working. I will see how far this takes me. I'm glad I slept on it, rather than dropping the pan. Thank you so very much folks.

[Erik L.]

I'm not getting any throttle control still.

[Erik L.]

I may have it, I'll let y'all know. Bless y'all.

[luvrbus]

I may have it, I'll let y'all know. Bless y'all.

Maybe the fast idle is turned on by accident

[Ed Hackenbruch]

Had that happen to me one time.  Going down the freeway in Colorado, had a dog that came running towards us so i reached up to pull the air horn cable to scare it away. Right after that i realized that i had no throttle, pulled over, got out, went to the back and opened up the engine doors and realized it was running faster than normal idle. Went back and found that i must have brushed my arm against the switch when taking my arm off the wheel and going for the air horn. Never even felt it.  

[ol713]

Also received this from Eric as well:

To: Phil Lyons <phil@busconversionmagazine.com>
Subject: Re: Bus conversions BBS Join Request

My 1980 MC-9 with a 8v71 is broke down on the highway with a low oil light. The oil is fine, it was just changed.

I plan on dropping the pan, and checking the pick-up for debris. I already deleted the oil to the alternator/generator. No leaks, current level reads full... I don't know what else it could be

  you said the "oil was just changed" - - - -  did you use the correct oil? Might be a silly question,   but have to ask the obvious.
                                                                               

[Erik L.]

Unplugging the bad sensor, is what fixed the issue. So simple, probably why I never considered it. This is my first diesel. I really appreciate y'all. Thanks again, everyone! 

[dtcerrato]

Aren't ya glad you didn't pull the oil pan! You done great coming to the board. 

[Erik L.]

Yessir! Something told me to wait. I'm glad I did.

[Busted Knuckle]

Now just be sure you use the right oil when changing it! Straight 40W no 15/40 as multi weight oil breaks down and give low pressure when it gets hot in a 2 stroke!
  BK