Assistance Needed, My Deuce is Sick

[jethrobyte]

Hi everybody, need some help. I recently drove my m35a2 on the interstate, and it acted like the engine was cutting on and off... It was after running it wide open on the interstate for about 10 min. When I first stopped, it shut off completely after idling. It took a while to get it to start again. After letting it sit a while, it still took a while to start (not normal) but ran fine for around 10-15 min. on the road, got into 5th for a while, and same thing happened.
I did recently install a Westfolk secondary spin-on fuel filter, which might have something to do with it... Maybe it's sucking air in, or I might have the wrong filter on it? Fuel starvation? What's really confusing me is it takes a while for the problem to show up. Once the problem starts though, it does not go away until it's shut down and sits for a while.
It seems to get a lot worse under full pedal down in 5th, struggles to get to 40mph.
Filter is a Napa 3352, 6 micron.
Any help/suggestions would be greatly appreciated, I would love to get it back to it's previous go anywhere running great performance!

 

[doghead]

Have you changed your primary fuel filter lately?

What are you running for fuel?

Your description sounds like what happens when you have a worn out hydraulic head, but let's eliminate everything else before going there.

 

[Flyingvan911]

Ditto. Primary filter is likely clogged. The engine sucks the fuel out of the secondary filters and runs out until the fuel can soak through the primary filter and refill the secondaries.

 

[jethrobyte]

Thanks for the replys!
No, you got me, I have not replaced the primary lately. Just running regular diesel. And now a trip to ebay..

 

[doghead]

The primary is under the alternator.

There is a bolt head on top of the filter base.

Do not spin the cup/can.

I loosen my alternator and swing it towards the motor to make it easier.

There are a few different primary filters. If you take out one that is stone like(like an aquarium filter), that one is "cleanable/reusable". Don't throw it away.

If it's just paper media, toss it and replace it. It never hurts to have a spare in the map compartment.

Do you drain it regularly?

 

[jethrobyte]

I do drain it (from the port on the bottom) regularly. Not much water, at least the last time I checked.

 

[Wildchild467]

I do drain it (from the port on the bottom) regularly. Not much water, at least the last time I checked.

I have drained my filter numerous times and I never get any water. Then again, I usually always have a full tank of wmo/diesel/gasoline blend fuel (less air to form condensation in the tank) and i drive my truck a lot. Maybe that combination keeps water away? Not sure.

 

[Westech]

Just replace the first filter with a spin on also.
So much more eZ to change out

 

[Wildchild467]

While you are at it, you could do other PM stuff that may or may not be related to your problem. Check/blow out the air filter, replace the secondary filters too since you have to change your primary and adjust the valves to name a few. I love preventative maintenance. It saves money in the long run and makes my truck more dependable. I don't have any doubt in my mind that my truck would make any trip I want to take with it. It is 100% ready to go at this moment.

 

[Droppedadeuce]

Primary, same thing happened to me last week!

 

[gimpyrobb]

I hav3 secondary filters for $5 each plus the ride. PM if interested.

 

[Jeepsinker]

If you can build a simple bracket you can use a napa spin on filter base and run a 10 micron primary filter with water drain. I did that just before the Georgia rally. Keeps the secondaries cleaner too.

 

[jethrobyte]

I try to keep the tank full to reduce condensation, seems to help. Yes, a primary spin-on will be my next investment. I have already changed out the oil filters and the secondary with spin-ons.
Update: Today I ran it until the problem started again, parked it, and it shut off again. I immediately opened the valve on the primary, only a few drops came out! Waited a few seconds, and more drops came out. Thanks guys! I do believe that is the problem, the primary! I have already ordered a new one.
This does make it obvious to me I need to take my maintenance more seriously, guess I had better start going through all those other things that probably need attention.
If I could ask yall one more question... When I was driving it today, (at night) I noticed the headlights got REALLY bright.. looked ay the voltage gauge, it was pegged out far to the right. I took it out of gear to idle... it went all over the place for a few seconds, then back to normal. It did all this one more time in my 15 mile ride. I'm guessing this has something to do with my generator, but I'm not sure exactly which sub-component may be to blame... Internal voltage regulator? Any ideas? I do have a spare, (gen) which I will swap out with when I do the primary fuel filter change, then get it tested I guess.. (not sure if a regular bench test will identify this intermittent problem..) Have yall run into this problem?
Thanks again guys!

 

[Jeepsinker]

You know you can get the primary filter at Napa right? For the electrical check your ground terminal at the frame from the batteries. Mine broke off today. The voltage was jumping around a bit until it broke off, then it pegged.

 

[Rmtaunton]

You know you can get the primary filter at Napa right? For the electrical check your ground terminal at the frame from the batteries. Mine broke off today. The voltage was jumping around a bit until it broke off, then it pegged.

Agreed , I would certainly check grounds

 

[doghead]

Or any of the cables being loose could cause that.

 

[Flyingvan911]

I cleaned the cable to frame connection after I got my truck and it made a huge difference.

 

[Jeepsinker]

I you have the time and money it isn't a bad idea to just replace all of the battery cables. The positive cable from the battery to starter should be sheathed in a three foot piece of 3/4" heater hose when you replace it because it is prone to chafing through where it lays on the motor mount. When I pulled mine yesterday I was quite surprised that it never shorted and caught fire. Also, loose connections at any battery terminal will melt the terminal and ruin a battery. Doghead is quite right. I check mine all for tightness once a month.

 

[jethrobyte]

Yes, after looking at my battery cables, I have to agree, it would help to replace most of them. Jeepsinker, I like your idea of sheathing them in heater hoses, I do that already for my CB ant. cables, works great!

 

[Jeepsinker]

It really is a must for peace of mind. Once a main battery cable catches fire from a short there is little chance of putting it out in time to keep from burning the truck down. You have to use 3/4" heater hose and lube it with silicone spray lube to get the 1/0 cable to slide through. Of course, if you think ahead and run the wire through the hose before soldering the terminals on you don't have to do that.