Bus Conversions dot Com Bulletin Board
October 31, 2014, 11:46:56 PM *
Welcome, Guest. Please login or register.

Login with username, password and session length
News: If your computer is lost, damaged, or stolen, your Online mags will be safe.
   Home   Help Forum Rules Search Calendar Login Register BCM Home Page Contact BCM  
Pages: 1 2 [3]   Go Down
  Print  
Author Topic: Need engineering help understanding my check valve flow direction - Please!  (Read 4044 times)
plyonsMC9
Global Moderator
Hero Member
*****
Offline Offline

Posts: 1160


Big Wheels Turnin'


WWW
« Reply #30 on: June 29, 2009, 12:38:15 PM »

Hey Phil,

Since that nasty ol' generator is causing you so much trouble, I'll be glad to take it off your hands if you want to drop in down here in Texas for a visit. Heck, I'd even be nice enough to loan you some tools to remove it. I might even serve you a nice cold adult beverage at no charge, just because I'm that kinda guy.

 Grin

Dallas - you are "THE MAN"!!!!  And - you were too modest to mention, that if I simply let you remove the generator - it won't be failing any more when the fuel level gets low.  Totally Awesome!!!   Cheesy  Cheesy  Cheesy  Ha Ha - I have sooo much to learn.   Grin

Best Regards, Phil
Logged

Northern Arizona / 1983 - MC9
luvrbus
Hero Member
*****
Offline Offline

Posts: 12809




Ignore
« Reply #31 on: June 29, 2009, 12:43:29 PM »

He needs to disconnect his return line and check for air bubbles in the system the little engine will have a steady flow on the return if not he has a pickup problem and go from there. That would be my way of doing it
Logged

Life is short drink the good wine first
plyonsMC9
Global Moderator
Hero Member
*****
Offline Offline

Posts: 1160


Big Wheels Turnin'


WWW
« Reply #32 on: June 29, 2009, 12:49:43 PM »

So, I have several suggestions it seems which suggest the fuel line w/in the tank or in the 6 inches outside the tank may have a very small hole, and this seems to be the least expensive option to try next, would this be the correct place to start?  Can I put on steel tube fuel lines with flare fittings?  Or?  I know these are really basic questions, but I obviously don't mind humiliating myself in a public forum.   Cheesy

Then, if that checks out, I should move to diagnosing the solenoid or relief valve since those cost more and I could still have a hole in the fuel line?  The copper fuel line is about 5 years old now.

Finally, it seems that the check valve would be treating a symptom.  Am I correct?

Thanks again,
Logged

Northern Arizona / 1983 - MC9
Len Silva
Hero Member
*****
Offline Offline

Posts: 4086


Angle Parked in a Parallel Universe


WWW

Ignore
« Reply #33 on: June 29, 2009, 12:57:49 PM »

Phil,
I think you got it.  I am assuming that you have already ruled out an electrical/shut down problem as discussed in the previous thread.  The fact that moving the fuel pump closer to the tank helps, seems to agree with that.  Unless replacing the fuel pick up is extremely difficult, I wouldn't sweat the copper vs steel at this time.  Just do what is easiest until you have resolved the problem.
Logged


Hand Made Gifts

Ignorance is only bliss to the ignorant.
kyle4501
Hero Member
*****
Offline Offline

Posts: 3146


PD4501 South Carolina




Ignore
« Reply #34 on: June 29, 2009, 01:05:55 PM »

I'd do what luvrbus said about looking for bubbles in the return line first since it is easiest, just take the return line loose & let it flow into a fuel can. If air is present, you know an air leak is the problem. Unfortunately, all clear doesn't mean there isn't an air leak under braking tho . . . .


BTW, your copper lines may be fine & outlast the bus, I only mentioned that because they could be part of the problem & merit a look-see.  Wink


Yes, the steel (& stainless) tubing can be used with flare fittings. I like the good ferrule fittings better tho. . . . But they are pricey . . .
http://www.grainger.com/Grainger/items/1WVR5

http://www.grainger.com/Grainger/wwg/productIndex.shtml?L2=Carbon+Steel+Compression+Tubing&operator=prodIndexRefinementSearch&originalValue=steel+tube+fittings&L1=Fittings%2C

Logged

I know you believe you understand what you think I said, but I am not sure you realize that what you heard is not what I meant. (R.M. Nixon)
luvrbus
Hero Member
*****
Offline Offline

Posts: 12809




Ignore
« Reply #35 on: June 29, 2009, 01:10:52 PM »

Phil, rule out the relief valve because you don't have one on the Kubota return line it's only purpose is to dump unused fuel from the injectors back to the tank.If you are getting air in the system from a leak it will show on the return line in the form of bubbles.The way I check for bubbles is removing the return line and insert a short piece of clear plastic line with a connector and watch for bubbles works like a sight glass. 

good luck
« Last Edit: June 29, 2009, 01:27:33 PM by luvrbus » Logged

Life is short drink the good wine first
Sojourner
Jesus Love You!
Hero Member
*****
Offline Offline

Posts: 894


WWW

Ignore
« Reply #36 on: June 29, 2009, 08:24:40 PM »

Kyle, he does have a return line to the tank on a Kubota, I for one still think it a shut solenoid problem you don't start one of these easy if air is in the system or it ran out of fuel,leads me to  think it is shutting down at the pump.
The way mine works is 12 volts opens it to start 110V keeps it open for running.
I had this same problem with mine a while back replaced all the lines to the tank and it still would shut down so I did the old bungee cord repair to hold the solenoid open and it never shut down mine has the shut off on the side of the pump his may be in the pump. Or he could have a bad shutdown sensor telling the engine to shut down  

  good luck

Phil...I wasn't sure that your Kubota already has a fuel return line...which means you don't need another one (relief valve or bleeder).
I would try what luvrbus have done...it to see if it the "shut down soleniod" is the cause of the shutting down when braking. I would temporary hold it open via cord or whatever and then road test it. If it keep running....then you need pin points from the schematic to see which sender unit or relay or loose connection. A fuel pressure sender unit can be out of calibration such as set too high of press before it energize the shut down soleniod. Or better yet call Wrico or whoever the manufacture support rep about the possible shut down system working during braking. They should know the where to check for the bad part

Sojourn for Christ, Gerald
« Last Edit: June 30, 2009, 05:00:38 PM by Sojourner » Logged

http://dalesdesigns.net/names.htm
Ps 28 Blessed be the LORD, because he hath heard the voice of my supplications. The LORD is my strength and my shield; my heart trusted in him, and I am helped: therefore my heart greatly rejoiceth; and with my song will I praise him
JackConrad
Orange Blossom Special II
Global Moderator
Hero Member
*****
Offline Offline

Posts: 4447


73' MC-8 8V71/HT740 Southwest Florida


WWW
« Reply #37 on: June 30, 2009, 12:47:06 PM »

I just remembered a PowerTech Generator (Kubota engine) that had a similar problem. I found a poor connection on the engine stop solenoid. The are 2 wires on this solenoid, one is the coil that activates the solenoid and the other is the "holding" coil.  Both ground through the solenoid body to the engine. I removed OEM connections and soldered the wires directly to the solenoid.  Jack
Logged

Growing Older Is Mandatory, Growing Up Is Optional
Arcadia, Florida, When we are home
http://s682.photobucket.com/albums/vv186/OBS-JC/
luvrbus
Hero Member
*****
Offline Offline

Posts: 12809




Ignore
« Reply #38 on: June 30, 2009, 02:03:34 PM »

Jack, the adjustment on the units are very critical if not right on the money it will make the holding part not work all the time and eventually stop working all together fwiw  been there done that    good luck
Logged

Life is short drink the good wine first
JackConrad
Orange Blossom Special II
Global Moderator
Hero Member
*****
Offline Offline

Posts: 4447


73' MC-8 8V71/HT740 Southwest Florida


WWW
« Reply #39 on: June 30, 2009, 03:36:23 PM »

Luvr,
   I don't remember seeing any adjustment on the model I was working on, but I did not remove the solenoid from the engine.  I replaced the bad spade terminal by soldering the wire directly to the terminal.  Jack
Logged

Growing Older Is Mandatory, Growing Up Is Optional
Arcadia, Florida, When we are home
http://s682.photobucket.com/albums/vv186/OBS-JC/
plyonsMC9
Global Moderator
Hero Member
*****
Offline Offline

Posts: 1160


Big Wheels Turnin'


WWW
« Reply #40 on: July 02, 2009, 10:57:13 AM »

Oh Good Grief!  I just learned that soft copper has a different measurement scale than rigid copper.  I thought they were the same - and I was WRONG! 

Isn't this embarrassing!!  Embarrassed   Embarrassed    Sorry for providing bad information.   

I compared my fuel feed line w/in the fuel tank to some copper tubing I had, and measured & knew to be 1/2" - thus I "thought" my copper fuel line was 3/8 of an inch.  I have since found out that actually, my fuel feed line is 1/2" soft copper.  Waaay back in this thread, one of the first things said by Wrico & Others was that the fuel feed was supposed to be 3/8 to 5/16 inch line.  And that too large of a fuel line would lead to loss of prime issues. I am assuming this measurement is in soft copper, not rigid. 

Are there thoughts on using 1/2 inch fuel lines (soft) for pickup - e.g., is this too large?   That would invalidate one of the underlying assumptions I presented.

If so, It looks like I need to replace the line w/ smaller diamater line - then see if I still have a problem.    I had purchased some steel 5/16" line, but need to get new fittings.  AS the bus is about to leave again on a trip, I have put everything back together.

Thanks again - and please accept my apologies for the bad measurements!

Phil
 


Logged

Northern Arizona / 1983 - MC9
Pages: 1 2 [3]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.18 | SMF © 2013, Simple Machines Valid XHTML 1.0! Valid CSS!