powerstroke idling vs. cummins idling

[jkh]

A friend of mine has a 97 powerstroke that he leaves idle whenever he stops in. Sometimes it is a half hour or better. Before I tell him it is not a good idea I want to make sure powerstrokes have the same concerns as cummins,ie. low cylinder pressure at idle which will cause rings not to seal, low cumbustion temp ,etc. , or are they designed different.

Also do the big trucks have the same concerns,and if so how do they sit and idle for hours on end.

thanks

 

[Alan Reagan]

All diesels have long idleing as a concern. It was a problem restarting them years ago so drivers left them idleing. Washdown will occur as unburned fuel (due to cold cylinder temperatures) settles on the pistons and flows past the rings. Buildup will occur on the rings in the form of carbon. Fuel goes into the oil and dilutes it. Injectors start to stick.



My brother in law and next door neighbors leave their 'strokes idleing because they have trouble starting them on cold days. It is not uncommon for either of those trucks to sit and idle for an hour or longer. They say "the trucks are diesels..... they are made for idleing. " I say BS. They are made to work, not idle.

 

[fj40charles]

Originally posted by Alan Reagan

All diesels have long idleing as a concern. It was a problem restarting them years ago so drivers left them idleing. Washdown will occur as unburned fuel (due to cold cylinder temperatures) settles on the pistons and flows past the rings. Buildup will occur on the rings in the form of carbon. Fuel goes into the oil and dilutes it. Injectors start to stick.



My brother in law and next door neighbors leave their 'strokes idleing because they have trouble starting them on cold days. It is not uncommon for either of those trucks to sit and idle for an hour or longer. They say "the trucks are diesels..... they are made for idleing. " I say BS. They are made to work, not idle.

Maybe the PSDs are made to idle and not work?

 

[RustyJC]

Don't the Powerstrokes have a "warm up valve" - a butterfly in the exhaust downstream of the turbo like an exhaust brake? In fact, there are aftermarket Powerstroke kits that turn on this warm up valve to function as a poor man's exhaust brake. If this valve were to engage during extended idling, it would serve the same purpose as turning on the e-brake on a Cummins - that is, it would keep the EGT's high enough to prevent varnish formation on valve stems during extended idling periods.



Rusty

 

[illflem]

Easy way to tell if a engine has been over-idled is to sniff the dipstick. If it smells like diesel you had better start turning it off more.

 

[Alan Reagan]

RustyJC, They may have this butterfly, but my brother in law's truck sounds the same anytime I here it so it must stay open on his all the time. He cranks it in the morning and it runs for 30-45 minutes before he goes to work. I know because his property adjoins mine and I hear it. Then, he comes in in the afternoons and leaves it running. The sound of the engine is pretty constant so I don't know how you tell when that thing is open or closed.

 

[Soldier]

RustJC, the Powerstrokes do have a "warm up valve" called an EBV (exhaust backpressure valve). This valve engages for cold starts to warm the engine faster, but once the engine is warm the computer opens the valve back up. It normaly wont shut again untill it's needed for another cold start.



When the valve is closed it will give kindof a hissing sound. A lot of folks unhook these valves because the sound of them is anoying.



Those aftermarked kits to turn them into an exhaust brake are a total joke! They charge out the wazoo for those and I (along with many of the Ford site) build the same thing for less than $40, and I can be done a lot cheeper. There's another product out there for the PSD, I cant rememer the name for it, but it basicly is nothing more than an expencive way to do a mod that we've been doing for forever for less than $10, I think they're charging around $300



The best thing to do for extended idleing, on any diesel, is some sort of idle controler. I build one for my truck using a few relays, potentiomiter, a on-off switch, ans a little bit of wire. Now I just flip a switch and adjust a knob to what ever RPM I want it to idle at. That's the good think of a 'Fly By Wire' throttle system. The ground is hooked up to the parking brake so it will only work with the parking brake set for safty.



The big rigs have something simular. Some of them can use the buttons on the Curise controll to adjust their RPM's. I've tried to find a way to do that, but I aint THAT good with electronics.

 

[RustyJC]

I guess I don't worry too much about it. If I'm gonna be idling for very long (like hitching or unhitching my 5ver), I'll just turn on the Jacobs exhaust brake. I also use it to warm up the Cummins on a cold start - I'll let it idle against the e-brake while hitching up the 5ver.



Rusty

 

[bmoeller]

Originally posted by Central Texan





Those aftermarked kits to turn them into an exhaust brake are a total joke! They charge out the wazoo for those and I (along with many of the Ford site) build the same thing for less than $40, and I can be done a lot cheeper. There's another product out there for the PSD, I cant rememer the name for it, but it basicly is nothing more than an expencive way to do a mod that we've been doing for forever for less than $10, I think they're charging around $300

Western Diesel makes one called "Turbo Brake. They are currently making two versions.

 

[Rob Thomas]

I did some work on a PSD a few weeks ago, then took a ride upto the store, left it runnin' while inside the store, came back out and the idle was much higher. Drove back to the shop, got out, let it set for a few minutes, bada bing, idle goes up. Aparently there is some sorta automatic high idle on them, it was pretty trick acctually, the truck was a '00 model.





Later, Rob

 

[Soldier]

Do you know if the owner has an AIC on it? It comes as an option from Ford. It's a white or gray box mounted on the transmission hump with some buttons and a digital display. It has a lot of neat features, it will automaticly increase the RPM as needed to help with things like winches, PTO, that sort of thing. You can also set a certain RPM so that when you push the button that looks like the Ford logo, it will go up to that RPM and hold it untill you turn it off.



I'm not sure if an automatic high idle is one of the features of it, but it wouldnt suprise me. That's one cool little box!



Also, I dont know much about the programing in the 99+ trucks, I mostly only care about the 94-97 PSD, but it may have it programed into the computer. I know that some of the older Ford diesels (7. 3 liter non turbo, and maybe the 6. 9) had that.

 

[pdolan]

The high idle feature is in all PSD 7. 3s except Calfornia or other cold weather delete locations. It looks at the EOT (Engine Oil Temp) and closes the EBV and kicks up to idle to 1100 with the parking brake set. The EBV will also go on at part throttle when driving with low EOT to aid warmup.



At really low temps, the airflow under the truck drops the EOT into the EBV engage range all of the time, even though the rest of the engine is toasty warm and working hard (even happens towing heavy).



The AIC is a really good idea for extended idling, but must be invoked to set RPM.



Pat

 

[Rob Thomas]

CT, no it didn't have AIC box, I didn't use the parking brake either, (auto) just put it in park and, wala.





Later, Rob

 

[COBRAJET]

My 99 PSD would run at different speeds when cold. If you started it when it was below 40 degrees or so the EBV would close part of the and the idle would kick up. If it was very cold out... below 20 or so the EBV would close even more and the idle kicked up even more. It would do this while driving at times. There were several instances while in CO. in the winter that it would kick in and out while idling at lights. It appears to work pretty good in cold weather, but does not do a bit of good in the summer although here in TX. I am sure the truck keeps hot enough to keep the temps up. The device was installed in order to heat the occupants up quicker... . a nice idea, the Cummins can take up to 10-15 minutes to produce any cab heat on very cold days... CJ

 

[Rob Thomas]

Originally posted by COBRAJET

the Cummins can take up to 10-15 minutes to produce any cab heat on very cold days... CJ

Ahhhh, the beauty of electric fans, and a PS high-idler, heat in no-time.





Later, Rob

 

[Alan Reagan]

Originally posted by Rob Thomas

I did some work on a PSD a few weeks ago, then took a ride upto the store, left it runnin' while inside the store, came back out and the idle was much higher. Drove back to the shop, got out, let it set for a few minutes, bada bing, idle goes up. Aparently there is some sorta automatic high idle on them, it was pretty trick acctually, the truck was a '00 model.





Later, Rob

Rob, that truck had the high idle carburetor option. I'm sure.



My BIL's sounds the same. I've never heard it speed up. I've driven it a couple of times (dressed in disguise) and never noticed a faster idle after stopping, but I didn't put on the emergency brake. His new one is an '02 model but he also has an '01 (backup transportation).

 

[lmills]

My freind's PSD does the same thing. He doesn't have any box added either. He got out of his truck to talk to me the other day at work and left his truck idel. After a couple minutes the idel ramped up. He said "that thing drives me nut's, if I get in and tap the brake it will come back down". I explained to him that it must have been a factory installed ideler for cold weather and that he should let it do it's job. Now he likes it. He won't stop telling everybody about how nice it is.

 

[Rosco]

The "box" you guys mentioned is a option that has to do with the charging system. At work our rescue trucks (ambulances) have this feature. When you set the e-brake it goes to a preset high idle (which can be adjusted with the box) then if the charging system is still struggling it will keep raising the rpm's. One of our trucks needed batteries or something and when we came out of a house with a patient on the strecher the truck was out in the street screaming away so bad I thought she was gonna blow. This box may also be used for pto operations but I think its main purpose is charging.



My above statement does not mean that regular powerstrokes don't have a high idle feature just that the "box" is optional.



Also '03 Cummins have a high idle feature that kicks in when it's below 32 degrees.

 

[CUMAPART]

It seems to me that the PSD hi-idle feature works a lot more often than the one that is programed into our trucks. Mine will work when it's supposed to but once the Cummins is warmed up a little bit it will stop. Example My friend (PSD owner) and I left work the other night both of us stopped at the Quick-mart a couple miles down the road for a coffee left trucks run while we went in came out his was up to 1100rpm mine was just at idle. I know that the trucks were warmed up a little bit but the PSD hi-idle seems to work more often. I guess ours doesn't have to.

 

[speedracer]

jkh, your friend idling his truck for a 1/2 hour or so isn't going to hurt anything. Assuming it was up to operating temperature when he parked it, that isn't long enough for the engine to lose enough temperature to have cylinder washdown. On the other hand, there's no real benefit to idling it either, just wasting fuel.