New Member, Needs Help!

[Paychk]

When all else fails go back to the T/S tree and start fresh, thats what I did.



Don in one of your post you said that it died coming to a stop & hard to restart, the manual list a bunch of checks and one that hasn't been checked is your idle speed? Have you checked that? with auto trans 700 RPM A/C on or try to hold the throttle open some when you are starting? The other is, unexplained shut down & restarting after waiting a period of time. The manual states to check the manifold drain line for a restriction, this will cause a rise in the case pressure of the injector pump preventing injection. Max restriction is 20. 4 in Hg or 518 MM Hg. there is a drain off the injector pump that tees with the drain manifold from the injectors.

 

[DonTX]

Paychk: Been there and done that. Even though the CEO of Monaco Coach is the same guy that used to be at Executive Industries (Kay Toolson), they disavow all knowledge of this one, and the several years of making them with the Monaco name on them even! I don't know why, apparently some very bad feelings somewhere in that situation.

Yep, the return lines were one of the first checks, they are clear. Idle is spec at 800 in some book I have, it is plenty fast, stall was the engine dying while slowing down to a stop, but while still rolling



1stgen4evr: I intend to disconnect all wires from the solenoid, and jump from the battery to the solenoid, with no other things maybe drawing it down.

 

[DonTX]

Wrong Pump Even

Well, this is almost embarrassing, but I just found out I do NOT have a VE44, but what it has is a Bosch VP14, shows on the build sheets. Can you believe that? I can't even recall how I came to believe it was a VE44. Anybody know anything about a VP14? Blood is starting to come out of my ears again, I am going to bed now. No wonder I can't fix it, hell I can't even IDENTIFY it.

 

[Paychk]

One last thing I forgot to post from yesterdays reading, is the manual stop lever firmly spring loaded to the run position?



Man! all I can say is I hope you don't give up on this, cause it is driving me nuts... I would like to know what is causing this! And I don't even own this thing.

 

[DonTX]

The manual stop lever is very hard to see, but with mirrors and camera shots it appears to be not only spring loaded into the run position, but is safety wired to run position as well.

Giving up has never been an option. This is all about intelligent troubleshooting, to get to the problem with the minimum number of steps. Kind of a game I love to play. Oo.

 

[Paychk]

This is all about intelligent troubleshooting, to get to the problem with the minimum number of steps. Kind of a game I love to play. Oo.

I second that!

 

[cojhl2]

I third that!



Out here we are all receiving a wonderfull education and we are doing it on someone elses $ !



Heck,, we are just like the govt!! (Cept for the education part,, they dont seem to get much smarter)

 

[Demons_Ram]

Took me forever to read down to here!

Don,

Somethings bothering me about this especially since you say the vehicle was running fine before. I'm a believer in the old KISS troubleshooting methods. Something we maybe over looked. What was the first mechanical change you made preceding the running problems? Did you say you changed the fuel filters?

Can you post a diagram of how you fuel feed system is hooked up now after you modified it with the water seperator? If you can go from the tank and include all filters in line ending with the injection pump.



Years ago we had a problem with a M-1008 military pickup. It had the 6. 2L and distributor type injection pump. It ran a lift pump off the bottom of the block feeding it. It also had a filter block on the firewall with the water in fuel light sensor incorporated in it. Well, everytime it sat for a while it would lose it's prime and damned if we could figure it out at first. Turned out to be small seals inside the filter block that were letting air into the system because they were old, dried, and cracked.



Also, we did a fuel filter housing size upgrade on a M-936 wrecker with a cummins NHC 250 one time and my guys didn't get a good seal on the new lines and fittings that were installed. This truck also lost it's prime frequently.



Quote from Don/TX ""Another strange thing. I have the dual filter setup for the fuel secondaries. When I pulled them just to put on new ones, they were clean and nice, some light rust on the top portion insides, but the final one had a piece of what looked like ceramic or hard plastic laying on top of the filter! It would be quite impossible for it to have come thru the first filter or the "strainer" primary of course, or even the lift pump. It appeared that it might have been a portion of some circular bushing or something. Size about 1/4 inch by 3/16, 1/16 inch thick. Any idea where that might have come from? I think Dodge used the single one, here is a view of both types""



The hard plastic material you had laying on the filter could have been a plastic/nylon sealing ring from up in the filter mount housing. Can you see up inside it from underneath to see if it's the case? If not how about a mirror?



I don't know your inline filter setup but, looking air bleeds before replacing that pump makes sense. The basic things like proper voltage to the solenoid and fuel pressure need to be looked at first as well. I would run with the solenoid elimination after that.

 

[DonTX]

Demons in the Cummins

OK, will try to answer all that in order. I made NO mechanical changes before the demons arrived. It was starting fine at the home of the guy I bought it from. In fact we slept in it at his place that night, and I started it easily the next morning to head home, 200 miles away. The first problem surfaced about 30 miles away, I stopped for coffee, shutting it down since it had no starting problems. Coffee down and it would not start! That was the start of the problems. I used WD40 for starting aid, it fired and off we went. An hour or so later, had to stop for bladder, but was smart, not going to turn it off this time! Fooled again, as I was slowing down for the turn into a truckstop, it died while rolling to the turn. Luckily I was rolling fast enough that with no power steering or brakes, I was able to roll it into a parking space. Lots of WD40 and maybe starting fluid, finally got her going again. It repeated this trick at a stop light later. Got it going finally, started the genset in case I was losing power to the solenoid (NO test tools at all along, big mistake!) It was getting evening, and the next 100 miles home were uneventful. The batteries were not the best, so I replaced them with new (it uses 5 batteries for starting). Still did not fully correct the problem, starting was an if situation, and continuing to get worse. The lift pump had been found to not pump fuel by the manual lever, so priming was impossible, then found out the lift pump was shot. Replaced that, primes easily now, but still had starting problems getting even worse. Decided that perhaps it was sucking air in the 36ft aging fuel line, wanted to put on a DAVCO unit anyhow, so did that. Eliminated any chance of air sucking, since you can pour fuel into the DAVCO directly. DAVCO is only a foot or so from the lift pump. The DAVCO actually replaces ALL the fuel filters, this setup originally had a "fuel strainer" on the tank side of the lift pump, and a dual filter setup on the pressure side of the pump. I have not yet eliminated the two secondary filters, but replaced them for the time being to eliminate them from problems. Obviously any leak there would be visible as a leak, since it is on the pressurized side of the lift pump, Suggestions were made to get the injectors serviced, so I pulled them, one was scored and stuck, the other five were in fine shape. Overhauled injectors installed and it did not help the starting problems of course.

Diagram of fuel feed, instead of drawing, fuel line from tank direct to DAVCO (DAVCO has a check valve in it in case you did not know that). Short line of a foot or so from DAVCO to lift pump (which as a diaphram also has a check valve). Steel line from lift pump to filter housing, thru two filters and on to injector pump. The dual secondaries was a customer ordered option from Cummins, and has a bleed screw in the housing. Fuel flow and pressure are quite adequate there. One can see from the lowering of fuel level in the open DAVCO that fuel is going into the injection pump, plenty of fuel. One can also see that there is no air sucking in, and no drainback (it would have to drain back uphill the way it is plumbed. ). One could suspect the short rubber hose type line from DAVCO to lift pump of course, but the visual of the bleed shows no restriction or air leaks.

I am next supplying full direct 12v to the stop solenoid, and after that a solenoid pull is to happen. After that, it seems to be pump time for the VP14 Bosch. Oh yeah, I am about to install a fuel pressure gauge on the filter output banjo bolt.

 

[BushWakr - RIP]

Next time someone says they don't wanna pay $35. 00 for the TDR membership you might want to point out that a "new guy" got 3280 "reads" and 168 "replies" with his first run at the problem..... THAT IS WHAT THIS PLACE IS ALL ABOUT GUYS.....



pb.....

 

[DonTX]

You sure got that right BushWakr, I had even forgotten that it cost a few bucks. Even more, what is not showing up here is dozens of private messages with help, as well as manuals and documents emailed to me, even a replacement for a lost in the gravel banjo bolt!!. I have quite a library just from that help.

I am not there yet, but it is a great time to say "Thanks" to the people that have helped me get to this stage. I really appreciate it.

 

[DonTX]

Eureka!

Got to try something on you for thought guys. I was out playing today, checked the voltage to the stop solenoid, around 11 with the ign switch on. When turned to cranking position, the voltage to the solenoid dropped to 5. 02 Volts while cranking!. Now one of the books I have says it takes 8. 8volts to activate the solenoid!

Thinking I could fool it into working, I hooked up a hot wire from the starter main to the solenoid. That then runs the oil pressure gauge backwards, turns on the low oil pressure warning light, and some sort of a warning beeper that apparently tells you that the low oil light is on and you have low oil pressure, not quite sure what to make of all that yet. Also, you can hear a click when the 12v is present, indicating that the solenoid has a good coil and is picking up the plunger. Cute, glad to know that, in case I ever run out of oil.

I am now of the opinion that what is happening is that when I hit the starter, the solenoid drops to close off the fuel. When starting fluid is introduced, the engine starts on it, starter disengages and the voltage goes back up to enough to open the solenoid and let her run. What is wrong? Well, I don't know yet. Maybe bad ground somewhere, maybe the low oil pressure shutoff is shorted out, etc, etc.

 

[DonTX]

Banjo Bolts

And oh yeah BGilbert: As you suggested, after I got the banjo bolt you sent installed and got it running, wife looked down at the gravel we had searched for hours, and yep, there was that darned banjo bolt!!

 

[JLEONARD]

 the voltage to the solenoid dropped to 5. 02 Volts while cranking

Wasn't it about 162 messages ago somebody suggested breaking out a voltmeter :-laf :-laf

Don't worry. . I'm not flaming... I'm just glad there's somebody else out there who needs a 2x4 the get thru a thick skull. :-laf :-laf Now I don't feel so bad.

Now you just need to decipher the safety shutdown system. Sounds like it may be set up like a marine genset. They have a switch that bypasses the low oil shutdown until pressure builds.

Jay

 

[bgilbert]

Got to try something on you for thought guys. I was out playing today, checked the voltage to the stop solenoid, around 11 with the ign switch on. When turned to cranking position, the voltage to the solenoid dropped to 5. 02 Volts while cranking!. Now one of the books I have says it takes 8. 8volts to activate the solenoid!

This wouldn't be an issue if you removed the plunger from the solenoid.



How about wiring 12V direct from the battery to the solenoid?

 

[PSchwering]

Don,

Great find. The paperwork I found today says the selonoid requires 10. 0 Volts to "Pull Up" & 8. 0 Volts to "Hold up" 5. 02 ain't going to Cut it.



How did you hotwire the pump? Did you unhook the wire from the Chassis that is supposed to run the pump? P.

 

[DonTX]

Sore

I am a bit sore from all that abusive "told you so". :-laf :-laf

I did not have time to disconnect the wires from the solenoid, just stuck a wire from the starter to it to see what would happen. With the oil pressure gauge wanting to wind up counterclockwise and the low oil pressure light and beeper going off, I did not want to burn something up. Will disconnect the solenoid wires and do an isolated 12v from my car battery for total test, to see if it opens and starts. I have had some reservations about poor grounds in this thing, got to start from the battery to frame ground and work back to the engine. With five fully charged new batteries, the dash voltmeter says only 5 volts or so when cranking, and the overhead lamps are flickering far too much to make me comfortable. Might need to check amps of starter draw as well.

Any help on safety shutdown systems diagrams based on the stop solenoid and oil pressure would be appreciated. Just cannot visualize that one.

 

[rlyons]

My guess without seeing the coach would be a simple system where the 12 volts from the ignition switch would go through the two wire pressure switch that you have in the picture and then on to the shutoff solenoid. This would come from the "run" post of the ignition switch. I think this would be bypassed when you turn the engine to start however by either a wire coming from the starter solenoid or from the starter switch. This makes me believe your no start is due to low voltage reaching the shutdown solenoid. I would check for 12 volts coming to that low pressure switch and for 12 volts going out of the switch with the key in the run position. I would then check the same with someone cranking the engine. You may have something with the grounds. The first step I would take is to feed 12 volts directly to the shutdown solenoid and see if it starts. If so then that narrows it down to low voltage reaching the solenoid. You also need to see how much voltage is at the battery side of the ignition switch when you are cranking the engine, if it is in fact only the 5 volts showing on the gauge the engine is never going to start until you get the voltage back up to at least around 9 or 10 volts. On a coach that old you are more than likely going to find a corroded connection somewhere. I don't think starter amp draw is an issue if it turns over fast and starts on either. You should have a main 12 volt lead coming from your batteries to the front of the coach. It will be run through a fuse or circuit breaker somewhere near the batteries, that is the first suspected corroded connection. The engine will be grounded either straight to the batteries or to the frame. Check this ground very close, look at the connectors where they are crimped to the cables, they will corrode in the connectors over time. By the coach starting and running well until you ran 200 miles makes me suspect corrosion somewhere in the wiring. This is going to be a time consuming process but there is no way but to check for voltage everywhere along the wiring until you find the voltage drop. I will sure be waiting to hear the solution to this problem. By the way are the batteries in the rear of the coach? Only wish i could get hands-on on this one.

 

[PSchwering]

Don,

How are your Batteries hooked? are all 5 in Parallell, & 12 V Batteries? Just want to make sure there is no 6V batteries in the system I have seen this before where a bad connection would cause the ignition system to only get power from 1 Battery. (1 six volt in this case) Really a Bear to Find. P.

 

[DonTX]

The batteries are five 12v in parallel, located at the front of the coach, engine is in the rear, all five are being used. This is not a normal RV system, as "normal" would have starting batteries and house batteries. Executive did it different. . There is another battery, that is used exclusively for generator starting, and I can connect it to the other five with a dash switch if needed.

I had wanted to clean and reconnect grounds and connectors anyway, so now is a good time. It is feasible that a poor ground or connection someplace is the ONLY problem with fueling this beast.



rlyons: Your schematic seems to make sense, will study that possibility some more. Voltage applied at the solenoid making the oil pressure go backwards blew what little mind I had left. Again, a poor connection can make things seem really whacky sometimes. Another friend with an identical unit had a ground problem, where the neg is just bolted to the frame up front, then a ground strap in the engine compartment from the frame to the engine. The hot one goes thru a master disconnect switch, I suspect that too, it seems not to be really smooth going on and off, like maybe burned contacts inside or such.

Thanks again for helping me think this one out guys!