Got somewhat of a newb question. I had one of the later model pumps that wouldn't run away, so I busted out the TIG and added some metal on the end. I turned it up farther than before (I can tell this because of the higher idle) and it still hasn't runaway. I can blip the throttle to WOT and it won't hang, it just drops down like normal. So I'm wondering, will this change at all with load on the engine? I'm just paranoid that I'm gonna be testing it and I'll leave it at WOT for a few seconds (under a load) and it will run away.

Also, if I can hold the pump at WOT just for a second without a load to test for runaway, will it change if I were to hold the pump at WOT for more than a second? I've just been running it at WOT for a second with no runaway probs yet.

Maybe I'm just paranoid because I've never had a pump that can runaway! Thanks for any advice.

 

Thought I would leave another thing to add here. Before you crack on the pump and start tuning, make sure the board you are using isn't bowed. I couldn't visibly see my board was bowed. But when i used it i found out it was. it wouldn't shut the engine off. test it out and make sure it shuts off the engine by blocking the turbo with the board first. and that air cant suck in around the board. Instead of having to run around like an idiot and find another one while your engine is on its last leg of run away. Wonder what jack A** did that (yes it happened to me, man..)

 

as far as i know, if it didn't run away or hang while sitting there, it inst going to run away while driving it

 

I'm pretty sure you're right. Just wanted to double check.

 

He's right.

My pump is a "hanger" but it won't run away. Seems to me like you could add a little more metal to that fuel screw...

 

I recently read a thread of a cummins running backwards. I'll see if I can dig it up

 

Yeah, mine won't even hang. I've got a few more threads on the fuel screw before it will bottom, but maybe I'll save those for a few days before a dyno .

 

ok from a stock motor how many turns does it take to get a runaway

 

Each pump is differant. Some cannot make one run away with a stock "Power screw". Some can do it just by screwing it in a few turns. You need to play with it until you find your "happy" point.
On mine I had to pull the screw all of the way out and braze a little on the end untill I could reach "Maximum Potential". Don't forget to get a pyro before doing to much!
Good luck and have fun.

 

i only turned it 2 turns from stock i dont think it will run away but i have had it at wot, if the motor is off and you pull the trottle wide open can you tell if its gonna hang?

 

No. It has nothing to do if the throttle it's self is going to hang up. Its if it fuels past it's point. Then you cannot stop it from fueling. What they are talking about is if the rpm's stay up after you let off of the throttle, even with the peddle cumming up off of the floor. At two turns I'd be preaty sure you are ok. Is that about a clear as Mud?

 

yea as clear as mud sorry for all the ?s i just bought my 93 yesterday and have alredy started on it. im used to the 01 cummins just puttin a programmer in it and rolling on

 

No problem that's the reason we are all here, to learn!

 

Nobody ever answered your "How do I stop it"

IF you do turn your fuel screw in far enough to hit runaway you better have a 2x6 around to put over the compressor intake .....That's the only way to stop runaway.

I ran my truck right at float - ie let off the throttle and it would kind of float a few seconds before it returned to idle -- for 6 or 7 months. No bad side effects ecxept scaring edit out of a couple kids in a powerjoke when they revved their engine and I revved mine and it didn't slow down right away

 

You can get away with that with an automatic trans, but it's really annoying with a stick...