m35a2 stalls out at higher rpms?

[svd dragunov]

Okay ive done some research about the deuce stalling out at lower rpms, but 2 days ago i started having the oppisite problem.

When i get it around 2200 rpms it seems like its losing fuel and stalls out. I had a similar issue 4-5 months back and it turned out i had a small leak in one of my fuel lines. Well i replaced the line and changed out all the filters. Problem solved.


Fast forward to now. Trucks starts and idles fine. No visble leaks on the ground or on the ip pump. I figured it was the one of the following. Filters. Pick up screen. Fuel pump. So i changed out all the filters. Pulled the intake screen. And double checked that the pump was working. All checked out. So im thinking somewhere its sucking air into the line.

I think ill double check the line i replace last time. Like i mentioned truck turns over and idles perfectly. It only gives me issues when i try to get up to speed. Its like a hiccup. where it stalls then gets speed.

Any way thanks for any suggestions.

 

[cattlerepairman]

Check copper fuel line for pinching, especially where it runs from one side to the other under the radiator. Check the rubber fuel lines (if so equipped) - when they rot inside, they can swell up or create "flaps" that can cause flow issues.
Also check whether the fuel shutoff releases completely.

You replaced the filters - what did the elements look like? Pristine clean or gunky? Thinking of algae in the tank.

 

[welldigger]

I'm unsure if bad HH o-rings can cause this problem but it wouldn't be a bad thing to check regardless.

 

[svd dragunov]

Check copper fuel line for pinching, especially where it runs from one side to the other under the radiator. Check the rubber fuel lines (if so equipped) - when they rot inside, they can swell up or create "flaps" that can cause flow issues.
Also check whether the fuel shutoff releases completely.

You replaced the filters - what did the elements look like? Pristine clean or gunky? Thinking of algae in the tank.

Old filters actually looked good. 1 wierd thing. On the primary filter there was what appeared to be hair. It looked like very fine blond childs hair. It was not present the first time I changed them. My first thought was that maybe it was from a rubber line. But they all checked out. Also forgot to mention I have good flow at the secondary filters as well. I did go over the line that I changed last time and it appers to be weeping at the fitting. Ill see about replacing the whole thing tommorow.

 

[svd dragunov]

I'm unsure if bad HH o-rings can cause this problem but it wouldn't be a bad thing to check regardless.

Id think it would cause issues at low rpm and idling problems. But ill check it out as well.

 

[6x6guy]

Try disconnecting the feed line befor the injector pump and install a clear plastic line to the output of the secondary filter output- empty fuel that comes out of secondary filters into container to assure proper flow from the fuel pump- just turn on power to system (engages fuel pump )- no need to start engine to assure proper flow from of fuel system to injector pump- check for flow pressure and air ( bubbles ) in system - then at least you can eliminate the fuel delivery system to that point.

 

[svd dragunov]

About how much flow should i expeect from the line? I know I get a decent ammount from the filter bleeder. Also I replaced the in tank with an in line some months back. Im wondering if maybe it cant keep up? Im probably going to go ahead and get a new in tank pump, while im at it.

 

[6x6guy]

Depending on the size of the hose, mine shot out over 8 to 10 inches, after I cleaned the in tank fuel pump screen at the bottom of the pickup nozel of the fuel pump-check for debri at the bottom of the tank that gets stuck on the screen then releases after the suction or pump is turned off and gets pickup again when activated and then again restricts the flow.

 

[svd dragunov]

Well i figured id post my updates. As I was checking lines, I found that the rubber line following the primary filter line was dry rotted and leaking. So i replaced that. I Replaced the tube on the in tank pump. Replaced the return line going back to secondary filters. After doing all that it was running slightly better. But low powered. So i double checked the out put from the secondary filters. .. barely a drizzle, almost seeped out. So that ment the secondary filters are yet again plugged.

At this point i decided to pump the tank. Emptied out 40 gallons of fuel into some plastic containers i had on hand. Tried running the fuel back through my filter set up. Even with a 10 micron filter it would plug up every 2-3 gallons. So this tells me that the fuel in the tank has been coantaminated by something.

I personally think somone deliberately put something in the tank. my reasoning for this is 1. the fact that my primary filter was plugged up with hair (and yes it was hair) which was not present the first time i changed the filters. and second the fact that ive personally filtered every drop of fuel thats gone into the tank with a 1 micron filter.


so i installed a lock on the tank and will be getting some fresh fuel and new filters and see what happens.


Anyone have any idea what somone could put in a tank that would cause this much plugging?

 

[cattlerepairman]

Well i figured id post my updates. As I was checking lines, I found that the rubber line following the primary filter line was dry rotted and leaking. So i replaced that. I Replaced the tube on the in tank pump. Replaced the return line going back to secondary filters. After doing all that it was running slightly better. But low powered. So i double checked the out put from the secondary filters. .. barely a drizzle, almost seeped out. So that ment the secondary filters are yet again plugged.

At this point i decided to pump the tank. Emptied out 40 gallons of fuel into some plastic containers i had on hand. Tried running the fuel back through my filter set up. Even with a 10 micron filter it would plug up every 2-3 gallons. So this tells me that the fuel in the tank has been coantaminated by something.

I personally think somone deliberately put something in the tank. my reasoning for this is 1. the fact that my primary filter was plugged up with hair (and yes it was hair) which was not present the first time i changed the filters. and second the fact that ive personally filtered every drop of fuel thats gone into the tank with a 1 micron filter.


so i installed a lock on the tank and will be getting some fresh fuel and new filters and see what happens.


Anyone have any idea what somone could put in a tank that would cause this much plugging?

Glad to hear you manage to track down some culprits. I do not know the history of your truck; sometimes, if diesel fuel with a (high) Biodiesel component is used, it does not like to sit for extended periods of time (months, years). It attracts moisture and algae can grow in it. They are usually small enough to create "slime" that can plug filters, but not the "green masses" people seem to expect. Of course, someone could have poured paint thinner etc. into the tank. Who knows.
As you are doing, clean it out well, run fresh fuel, new filters (again....spn-ons are great) and enjoy the newly found power.

 

[Valence]

Hmm, and here I was going to suggest looking at the air cleaner for the high rpm issues. Just a shot in the dark though as I'm probably one if the least mechanically knowledgeable here.

I sure hope someone didn't contaminate your fuel! Perhaps it was the last of some gunk already in your tank?

 

[svd dragunov]

Glad to hear you manage to track down some culprits. I do not know the history of your truck; sometimes, if diesel fuel with a (high) Biodiesel component is used, it does not like to sit for extended periods of time (months, years). It attracts moisture and algae can grow in it. They are usually small enough to create "slime" that can plug filters, but not the "green masses" people seem to expect. Of course, someone could have poured paint thinner etc. into the tank. Who knows.
As you are doing, clean it out well, run fresh fuel, new filters (again....spn-ons are great) and enjoy the newly found power.

No bio diesel. And no noticable slime. definantly Something as it would pretty much plug all filters in a matter of gallons. My father in law suggested maybe "drillers mud"? Apparently its oil based. We have alot of drilling companies around here so its not hard to get. AND my neighbor who doesnt really care for me has access to it. That in combination with the hair makes me suspect foul play. I mean really hair? That for sure is a sign someone was messing with it. Looked like someone pulled it out of a hairbrush.

 

[cattlerepairman]

Locking fuel cap:

http://www.steelsoldiers.com/showthread.php?66489-Deuce-locking-fuel-cap

And a trail camera in a good location to shoot pictures of whoever crawls around the truck...

 

[svd dragunov]

Already made a locking device. Used a length of chain attached to the tank mount then put a hole in a tab on the tank. then secured with padlock. Its more of a deterent than a stop all. I like the idea of the camera.

 

[gimpyrobb]

I would discard that fuel and fill up on a new batch. New filters all the way across the board. I don't know that Orings would cause this. Once you have fresh fuel and filters, you have a baseline to start from.

 

[gimpyrobb]

Let me add to what I just posted.
One time I started my truck and let it idle while I was doing a walk around. After a few mins, the truck stalled out. I put new filters in all the housings and started her back up. 2mins and it died again. I was really worried. I did some testing and it turned out I had a high volume of water in my fuel. Dumping EVERYTHING and replacing the filters(AGAIN$$$!) was what got me back to normal. I then went back to my "normal" fuel and things have been ok since.

 

[svd dragunov]

Thanks gimp, thats kinda where im at with it now. if all else fails youll be getting another pm from me

 

[welldigger]

Hmm, drillers mud you say? There are 2 types of drilling mud. Both of which would be VERY bad news inside of a fuel tank. The first type of drilling mud is basically bentonite clay ground up into a powder with a few chemicals added. Upon contact with water this stuff turns into a wad of snot. It will stick to everything. The second type of mud is a liquid polymer. This stuff is like trying to pour Elmer's glue mixed with snot. Both of these products would cause large clumps of gew. Though I have never mixed either with any type of fuel, so I'm unsure of how it would react in that situation.

 

[silverstate55]

Tampons dissolve in diesel fuel & are known to plug things up too.

 

[svd dragunov]

Tampons dissolve in diesel fuel & are known to plug things up too.

never heard of that..