pump prob new one i think

[stone4x4]

i have a 1989 ctd w/5speed

the prob

went to turn the fuel up when i turn the fuel pressure up the motor will not idle back down. it is fine til you hit the throtle then it won't come back down. if i turn the fuel pres pin back down just a half turn and it is fine I adjusted the idle screw with no help. This isn't not my first pump tune. Can anyone tell me what the problem is? Thanks, Stone

__________________

 

[JLEONARD]

Sounds normal to me. Someone else can explain the inner workings, but that's what happens.

 

[Niki]

You have to adjust the linkage also, I don't know if you mentioned that.

 

[stone4x4]

adjusted the linkage

never had one runaway like this

is there any way to get around this

 

[cerberusiam]

adjusted the linkage

never had one runaway like this

is there any way to get around this

On the verge of runaway. Its normal because the fuel is turned up across the curve with the power screw.



To correct disassemble the pump and setup the fuel curve by changing weights and levers on the governor assembly. You probably have some weak springs that are not pulling the assembly all the way back.

 

[stone4x4]

thanks i'll try that

 

[PToombs]

Or... . heaven forbid..... turn the screw back out some. :{

 

[dpuckett]

I agree with PToombs- turn the screw back a half turn or so. You said you got it to come back down to idle after backing it out, right? This is a danger of too much turning on the pump screw. The 114s and 184s tend to run away after a certain point; The 205s seem to be more immune to it, from what I have read.



Daniel

 

[stone4x4]

i cant find a good pic of the springs he is talking bout

all the post i found are to old and the pics don't work

anyone got a link?

 

[cerberusiam]

i cant find a good pic of the springs he is talking bout

all the post i found are to old and the pics don't work

anyone got a link?

I apologize, I didn't qualify my last post. To correctly get the fuel you want the pump will need to be completely dissassembled and the fuel curve reset, a total rebuild.



Back the power screw out until your idle returns correctly for now. You can gain some by adding larger injectors but for a lot more it will require pump off the truck mods.





Ptoombs and DP, lighten up a little. The guy is looking for info and knowledge lets not CRY about it. We all had to learn by asking and making what seemed to be silly assumptions so lets help him out.

 

[phillips5]

On the early pumps when you go close to 3 turns they will run away with themselfs. 2. 5 turns max is where i stay without pump disassembly. 2. 5 turns really gives a lot of extra fuel any way. my 90 cdt truck can create over 30 psi boost at 2. 5 turns . stock is around 17 19 or so.

 

[dpuckett]

For once, I wasnt trying to make fun of him or make a joke- I just wanted to clarify what he had said and make sure I understood him and his scenario. And, I was agreeing with what PToombs had said, about turning it back for now, though without the little eyeroller.



That said and out of the way, I think it would be prudent for anyone with a lot of miles or years on their pump to, at the very least, get new springs and seals put in, (or do it yourself if you have the time and skills) if you have any work done at all.



Maybe you need some stiffer governor return springs (or is it just one? I forget now) to keep your revs in check. We always want it to GO faster, but things need to come back down to earth as well. Kinds like in the "Best tips" sticky, someone mentioned upgrading the brakes, as these things need to stop as well. Same principle can be applied to the pump operations.



DP

 

[PToombs]

I didn't really mean it to be snotty sounding. I'm sorry if it sounded that way. Nobody had said anything about backing the screw out. Most of us want all we can get, but sometimes you have to back it out some.

 

[cerberusiam]

Nobody was out of line, I was just funnin' ya'll.

 

[stone4x4]

i got the pump off the truck and taken apart what do you have to do to change the fuel curve and what springs do i need to replace

this aint the first Ve i have had apart (it's just the first one i have wanted to modify inside) anyone got any links how this should be done?

thanks for all the help,Stone

 

[Greenleaf]

This was a Test..............

This was simply a test of the TDR Moderation System. Had the above posts required actual moderation, the two members in question would have been notified via PM/e-mail and their subsequent replies would have been deleted.



This concludes the test of the TDR Moderation System

 

[stone4x4]

any info on this????

 

[Greenleaf]

Are you asking *me* if I have any info on this topic?



Yes. What spacifics do you need? I have been through this more times than I can recall. However, I have never ventured inside of the pump to just change the flyweights. If that is what your asking, you need to speak with someone who has.



I'll say this much, the pump will pump more fuel via modifications, however when you begin to operate at very high rpm's, the pump will pump less fuel.

 

[cerberusiam]

any info on this????

I know the theory as described by a pump builder but no practical experience, yet. This is getting into the area of secret squirrel stuff most builders won't divulge so hard facts are tough to come by.



There is a limit to how much the stock pump pieces will push at what pressures, as Scott said, but unless you are looking for a new VE HP record it won't be an issue.



At the minimum you need to bebuild the pump with the newer impoved springs and pieces. That may help with the runaway condition.



Just be advised if the governor assembly is setup wrong it is entirely possible to pump 250cc per stroke at 1100 rpms.

 

[dpuckett]

Just be advised if the governor assembly is setup wrong it is entirely possible to pump 250cc per stroke at 1100 rpms.

MY GOSH!!! What kind of EGTs does that produce? Or was it on the stand? Pump RPM, or engine RPM?



DP