Injector Pump troubles...

[Idually]

Hey Guys... How is everyone? I'm sorry that I don't post up much, but I still "listen in" all the time...



How about this one. "Red"(the 6BT Ramcharger) has been running great for the last year and a half. Mind you, 275,000ish miles and counting. Last Thursday, the wife told me that se started up a bit funny. Almost like starting up in the cold(it's been warm here in Colorado)... Real rough. Didn't think much of it but this Saturday morning, I got into Red and the ole Girl didn't want to start. Cranked it a bit more and she fired up, but died a second or two later. Tried again. Started up, but the low idle was down a bit and the came up to "normal". (Here's where you "flame" me) No guages... I know... I know... Anyway, Red runs normal for the most part. Seemed to lack power a little. It was already on the list to do, so I Changed the fuel filter, and pulled the lift pump off to see if it was fuctioning. It is. Put it all back together and nothing...



This morning... No start... AT ALL! She cranks over but didn't even feel as though she was going to fire. Came inside, seached the archives on the TDR, went back out, pullled the fuel shut off solonoid to check it. Seemed ok. Put the solinoid back in w/o the plunger... Still no go.



It was acting like it had been run out of fuel. I remembered what MadMax's truck was lke to start whne he changed the injectors and did what Kurt(GLHS) did... cracked the injector lines... What do you know! Fired right up! Ran fine. So I let it run a bit while I tightened up the injector lines and cleaned up. Shut it down and let it sit for approx 10 minutes. Went to start it up again and NOTHING AGAIN!! Uh-oh.



So I cracked the lines again and started it up(yes it fired almost right away). Bled the lines again, tightened them up and went for a ride. Felt fine. Nothing unusual. Brought it home, parked in the drive, shut it down and tried to start it up about 30 secs later. Real rough start. Shut it down. Left it off for about 3 minutes... Nothing. NOTHING again.



I believe I'm getting air from the "o=ring" between the pump body and head. Is it possible for the fuel to bleed back that quickly from any where else? Is it worth it to pull the pump and change THAT "o-ring? Do you guys think it might be more than just that.



Ideas? I'm stumped and in the doghouse. It's my wife's D. D.



Any ideas or a rebuilt "ve" would be greatly appreciated.

Thanks in advance!!!

Andrew

 

[JLEONARD]

pulled the lift pump off to see if it was fuctioning. It is. Put it all back together and nothing...

My two year old pump appeared ok as well until it failed totally. I had some trouble for a couple of months... one time it wouldn't start... then a couple of times it quit while running... until it finally wouldn't start the engie any longer.

New pump problem solved. I cut the old one apart and one of the rubber check valves was all eaten away and broken. I think as the rubber got eaten the issues would come and go until it finally got bad enough to completely not function.

Of course the truck was loaded to the gills, I was headed to the boat for a nice long weekend, you get the drift... the good thing was that I was just within range of AAA towing

 

[Idually]

JLEONARD. Thanks! I will grab new one and change it out. Maybe I'm thinking wrong, but wouldn't there be enough fuel in the pump itself to start? Why would it start, with the injectors cracked? Just bleeding back and allowing air into the system?



Thanks! Andrew

 

[Greenleaf]

That O ring will leak (weep) fuel and cause a hard start or a no start if it sets for a couple days. Is it weeping fuel? It weeps cuz it be pressurized in there. Then the fuel drains out and you get air inside said pump. I don't know if air is pulled in elsewere or if it enters the leaking seal... ... ... ... ... ... ... .....



Pump rebuild: Lots of folks do it. I personally would never exchange or give any pump away untill I took it apart myself to visualize the damage. Generally speaking, there is "no "damage" to warrant a rebuild. Seals and a bushing/throttle shaft/spring set will do you.



Don't just replace the O ring. Take the pump all down and replace all seals/springs.

 

[Don Tanklage]

are than any specialty tools req to disassemble a pump?



how about reassembly?



thanks



don

 

[Greenleaf]

Yes.



Modified 12 point 1" socket for that three (3) sided plug in hydraulic head.



Torque wrench



Socket for three sided plugs (Cap screw w/dowel pin) that secure the gov assy (spring assy) into the case.



Heavy 1. 5 inch (I think) puddy knife. Sears calls theirs a "chisel"



Lots of very clean PLASTIC containers with CLEAN diesel fuel



Very long pin punch



Small pick set



Small steel rule with 64/th grads or equivelant. (equivalent... ... ... . ?????)



Probably others as they come to me... ... ... ... ... ... .

 

[Don Tanklage]

thanks scott



keep em comin...



don

 

[Idually]

Hey Guys. Thanks again!.



A little update... Still no go. I have tried 3 different lift pumps, checked the shut off solinoid, changed the gasket above the fuel heater. Brand new fuel filter, too. Still the same. It runs fine when I crack the injectors and get it started. I did discover that when I removed the fuel filter to changed to gasket above the fuel heater, there was VERY little fuel in the filter. Thaought that was sorta strange. Filled it before re-installing, got it started. shut it down and tried to start it 5 seconds later... No go. Decided to double check the fuel filter. Almost empty again! O. K. now that is not right.

I think I'm going to need to drop the fuel tank and check the connections at the sender. I found the bottom of the tank covered with a film of "schmootz"(diesel and dirt). Wasn't that way last week... Thinking I might find the problem there.



Thanks again. I will update soon.



Andrew

 

[PToombs]

Sounds you have an air leak in the suction line. Maybe cracked at the sender?

 

[Idually]

PToombs. Ding Ding Ding!!! We have a winner. That is exactly what happened. Dropped the tank last night and sure enough the "send" fitting is cracked. Since the sender is custom to my RC, I'm going to rebuild the top.



How does diesel fuel interact with steel?



It will only be the round "top" of the sender, so it won't be submerged but it will be wet from fuel more often than not.



Thanks again, guys!

Andrew

 

[PToombs]

Diesel won't bother steel, but if it's on the outside of the tank, I'd paint it to protect it from the elements.

 

[dpuckett]

Diesel and galvanized steel is a bad combo.



I was reading this thread, and thought of my recent broken return line, but you had something similar- a crack letting air in somewhere in the low pressure side of things. Glad you got it going again. Great minds think alike, huh, Pete? :-laf



How'd the RC front suspension holding up under 1000# of weight? I think a 4B in a 1/2T chassis SUV would make for killer MPGs.



DP

 

[Idually]

Again, I thank you guys! That was the problem. Cracked send elbow at the tank. Last weekend, I completely rebuilt the sending unit. This one will probably outlast the truck.



Daniel. I'm actually putting a 4bt into a Ramcharger right now...



Dodge Ramcharger Central - Cummins Diesel - Ram Truck - Power Wagon - Trail Duster - 4X4 - Plymouth - Chrysler - Mopar



It will be more focused for off-road, but will be streeable. Should get real good mileage and be fun to drive.



Thanks again!

Andrew