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Increasing idle on '04 Ram w/5.7 Hemi


dana60
09-16-2004, 02:22 PM
I need to temporarily increase and hold the idle RPM of a 5.7 litre Hemi to about 900 RPM to properly operate the hydraulic system we have installed on the truck. Any ideas??

BleedDodge
09-17-2004, 12:07 AM
I'd install a choke cable, and hook it directly to the throttle body, mount it under the dash or something. It's probably the cheapest way you can do it.

You're using a PTO? If it's running from a PTO you could just have it geared higher if you really want. It would turn the PTO faster at a lower engine speed.

praisethelowered
09-17-2004, 02:18 PM
What about using some kind of solinoid to kick up the idle like a/c does? BTW, what's a pto?

scoutinkeith
09-17-2004, 02:48 PM
PTO = Power Take Off. used for powering accesories.
I'm not to familular with the new hemis, but with their electronic throttle, it may be tricky to find a suitable place to attatch and auxilary throttle control. and even if you can attatch something, the computer may throw a code because the sensor on the pedal would be giving a diffirend reading than the one on the throttle body. it might be worth a trip to the dealership just to make sure that it can be done.

praisethelowered
09-17-2004, 10:38 PM
[QUOTE=scoutinkeith]PTO = Power Take Off. used for powering accesories.

Sorry to go off topic here, but I'm still unclear as to what a pto is. Is it attached to the engine or transmission? How do accessories attach to it? Thanks in advance!

LTJGWorth
09-17-2004, 11:37 PM
What most people would probably recognize a PTO on is a tractor. Like a farm tractor. It's a shaft that comes out of the back of the tractor and runs things like mowers, tiller, and other equipment. It's basically the same thing here, just on a truck.

dana60
09-18-2004, 12:11 AM
In my case...the PTO is mounted to the manual transmission. For my application, it operates a 25 gallon per minute hydraulic pump and is attached to the PTO by way of a drive shaft. The PTO is engaged by cable from the cab. The hydraulic pump operates a set of power tongs we use to screw 4 1/2" through 13 3/8" casing (metal pipe) together which is then lowered into oil & gas wells and then cemented into place.

When the tongs are engaged, raised or lowered...a hydraulically operated govenor mounted to the truck motor accelerates the engine to ~2000 RPM by way of a linkage that in the past was attatched to the throttle body. My problem seems to be that the motor idles as ~600 RPM...not enough to get the govenor to kick in enough to rev the motor. We feel that if we could increase the RPM to ~900, the govenor would engage consistently.

Another new challenge we now have with the HEMI is that it is 'throttle by wire'. There is no longer a linkage or throttle cable from the accelerator pedal to the throttle body...where we proviously attached the govenor linkage to. Now we are attaching the govenor under the hood to the accelerator pedal in the cab via a cable through the firewall.

Possible solutions we are considering:

An adjustable, hand operated cable that can be attached to (can't quite explain this) where the 'throttle by wire' begins. The problem seems to be though that even with a steady hand. the engine is either at 600RPM or accelerates slowly on up to ~1200 RPM

Custom engine software programming. When the engine is started when cold, it will idle at ~900RPM....but within about a minute slows down to ~600RPM. It seems with a little know-how, we could get it to stay at the higher RPM.

The service techs at the Dodge dealership tell me there is no way to set the idle higher like the "Good old days" with the turn of a screw.

Any other suggestions will be appreciated...Thanks

praisethelowered
09-18-2004, 10:32 AM
Thanks for all the info. The main reason I was asking is because I want to get headers for my 87 Ram, and many say they won't fit with a power take off starter, but from what you describe, that has nothing to do with the starter. I'm still trying to figure out whether or not I have a power take off starter.

dana60
09-18-2004, 09:00 PM
[QUOTE=praisethelowered) I'm still trying to figure out whether or not I have a power take off starter.[/QUOTE]

I have not heard of a PTO starter. I'd get under the truck & take a look at your starter to see if it looks any different.

You might consider installing a starter for a 1994-2001 Dodge. I'm pretty sure it will fit and it is smaller to allow for more clearance for the headers. The 2002 to present might be the same also...but I'm not sure.

BleedDodge
09-19-2004, 02:24 AM
Manual transmission? I thought you couldn't get a hemi truck with a manual transmission?

If the governor doesn't kick in until around 900 rpm, you could hit the gas pedal once to kick the revs up, and in theory the governor would hold the revs where it was designed to govern at, correct?

dana60
09-19-2004, 04:22 AM
[QUOTE=BleedDodge]Manual transmission? I thought you couldn't get a hemi truck with a manual transmission?

The 5.7 Hemi is the base engine on all 3/4 ton Ram's now...auto or manual tranny. The only other motor available is the Cummins diesel. The V-10 is gone for now.

The govenor we use allows the engine to return to the factory set idle. If we adjusted it so as to hold a higher idle all the time....the engine would rev to probably over 5000 RPM. Way too much for our application. And it usually does this (revs the motor) over 100 times per job! I guess I need to hire someone to set in the truck during the job to 'goose' the throttle a little at just the right time. As it is...the equipment operator is on the drilling floor and most times can't even see the truck.

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