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Rich Idle, Burning eyes

12K views 29 replies 8 participants last post by  coalroll4power 
#1 ·
well guys had my 12 valve for 1000 miles now, got everything figured out that i can without asking any dumb questions on here, after 5 days of going through wiring harnesses finding shorts and fixing the P.O. abortion of scotchloks everywhere on the truck, fixing the trailer wiring and trailer brakes; im finally ready to tackle the motor and how its running.

A set of gauges is next on my list as its hard to diagnose anything without them. a question on that actually, having a standard guys always recommend getting fuel pressure instead of tranny temp. do 5 speeds just not heat up or are they a non worry? i tow a 10,000 pound toy hauler empty so would be nice to know if i have to worry about this little 5 speed. i know boost and EGT are my other two big ones to get

as far as i know the truck is stock. fuel plate safety screw hasn't been touched, doesn't blow excessive black some or any at all with low boost. also a bit of an issue here P.O. chopped up the exhaust so all i have is a 3" straight pipe going back to the rear diff and then stopping. not being a welder and not paying $100 for a piece of tailpipe when a 4" mbrp kit is $380. on that note for exhaust i only want to buy it once, do the 12 valves have any issues with back pressure from the exhaust, hence can i use a 5" exhaust or is it overkill and just go with a 4", or does it sound way cooler to have 5" or does it sound like shhh?

back to the hazy idle, so as far as im concerned the motor is stock, it doesnt pull to hard when low boost, doesnt really smoke but again i cant really tell because i cant even see the tail pipe, it does however get up to 100 mph pretty quick in 5th gear though even going up steep grades empty, not sure if that is normal for a stock 12 valve i believed they were a bit sluggish from everything i heard in the past. anyways whilst trying to figure out my trailer wiring and being behind the truck messing with the plug in, the fumes coming off the exhaust were so bad i almost couldnt breathe and almost enough to make me tear up. smoke was a white ish haze maybe grey.

now i know diesels smoke when they are cold fine. this one smokes at idle all the time. when returning home after motor is fully hot everytime. before you point at oil, or coolant its not, i have a powerstroke i know what coolant smells like when it burns and usually when oil is being burnt you will see oil in the exhaust pipe, plus i havent lost any coolant nor oil. i do have a bit of white smoke coming out of the oil fill tube, but from what i have read normal.

this leads me to believe something had to have been done to the timing, or idle or something isn't running correctly. where do i start guys????? :help1:

i would go at it myself and spend countless dollars and time checking unnecessary stuff that i deemed important to fueling from the service manual but who really like wasting $$$ or there time when someone else could know the exact thing they need to do right?:confused013:
 
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#2 ·
Does it "pop" out the exhaust if you rev it up high? That is one symptom of slipped timing. One way or the other I would check the timing and not just by the pin.
 
#3 ·
doesnt pop at all out the exhaust, for your high rev test in neutral or under load? and to what rpm? I'm guessing no timing issues as it hauls around 10,000 pound trailer with ease.

timing is definitely something i should familiarize myself with i guess as i have read that is one of the ways to crank up power in these 12 valves
 
#4 ·
Mine burns my eyes, but I have larger injectors and cold timing.

Sound like unburnt fuel coming out and irritating you.
 
#5 ·
A set of gauges is next on my list as its hard to diagnose anything without them. a question on that actually, having a standard guys always recommend getting fuel pressure instead of tranny temp. do 5 speeds just not heat up or are they a non worry? i tow a 10,000 pound toy hauler empty so would be nice to know if i have to worry about this little 5 speed. i know boost and EGT are my other two big ones to get
Manuals don't generate the amount of heat that autos do. It's a non-issue. If you really want, add Fast Coolers to your trans. They increase your fluid capacity by 2 quarts which keeps things cooler.

as far as i know the truck is stock. fuel plate safety screw hasn't been touched, doesn't blow excessive black some or any at all with low boost. also a bit of an issue here P.O. chopped up the exhaust so all i have is a 3" straight pipe going back to the rear diff and then stopping. not being a welder and not paying $100 for a piece of tailpipe when a 4" mbrp kit is $380. on that note for exhaust i only want to buy it once, do the 12 valves have any issues with back pressure from the exhaust, hence can i use a 5" exhaust or is it overkill and just go with a 4", or does it sound way cooler to have 5" or does it sound like shhh?
A 4" downpipe is the largest you can run without getting quite creative in terms of routing the downpipe though the inner fender and down outside the frame. You have to be pushing serious, serious horsepower before a 5" system is going to give you much of a gain whether you start it at the turbo or after the downpipe. A 4" system doesn't even really give you that much of a gain until you're into the high-300s for horsepower. Back-pressure is a non-issue on turbodiesels. The turbo provides the exhaust valves with all the back-pressure they could ever need.

back to the hazy idle, so as far as im concerned the motor is stock, it doesnt pull to hard when low boost, doesnt really smoke but again i cant really tell because i cant even see the tail pipe, it does however get up to 100 mph pretty quick in 5th gear though even going up steep grades empty, not sure if that is normal for a stock 12 valve i believed they were a bit sluggish from everything i heard in the past. anyways whilst trying to figure out my trailer wiring and being behind the truck messing with the plug in, the fumes coming off the exhaust were so bad i almost couldnt breathe and almost enough to make me tear up. smoke was a white ish haze maybe grey.

now i know diesels smoke when they are cold fine. this one smokes at idle all the time. when returning home after motor is fully hot everytime. before you point at oil, or coolant its not, i have a powerstroke i know what coolant smells like when it burns and usually when oil is being burnt you will see oil in the exhaust pipe, plus i havent lost any coolant nor oil. i do have a bit of white smoke coming out of the oil fill tube, but from what i have read normal.

this leads me to believe something had to have been done to the timing, or idle or something isn't running correctly. where do i start guys????? :help1:
You're saying you have white/grey haze all the time, even hot? That's abnormal. Mine will still make your eyes water when hot, but visible haze goes away after the engine's been idling for as little as a few minutes.

I would check your timing (using the pins) and remove/clean your injectors and have them tested. Slipped or low timing can increase haze especially when cold and injectors popping low will haze more across the board.

I would not recommend setting timing by using the pins, but checking timing with pins is fine for the purpose of ruling a slip out as a suspect. If your timing is out of whack by more than a degree or so the pins won't engage and then you'll need to send the truck in or buy the tools to examine your timing more precisely.
 
#6 · (Edited)
thanks for the comments guys really appreciate them.

motorcitymadmen, i made you a video you can be the judge if its "popping" and let me know i got buddy to rev it as high as she would go, you can kind of see the haze coming out from the truck and that was after idling for 30 minutes so im sure it was up to temp.
here is said video https://www.youtube.com/watch?v=5e5l-mil8TQ&feature=youtu.be

common, i could care less about myself personally getting irritated or breathing the fumes. i just want this truck to run perfectly. haze coming out exhaust... not perfect.

dauntless89, no tranny gauge, save some bucks cool.

4" straight pipe also save some bucks, check, does SS vs aluminized make a difference in sound or anything or just looks?

so you are saying follow buddies post "timing in 40 minutes" just to check what my timing is but not to adjust? and if i do want to just get it adjusted take it into a shop and have them do it? (and be liable for the job).

im going to have to research into this pins you guys keep talking about, not familiar with timing yet. havent watched buddies "timing in 40 minutes" video yet maybe it will provide me with more insight.

im assuming injectors not "poping" is a common issue with 12 valves, its got 270,000 kms(170.000 miles) on the ticker im sure its broken in enough and due for some big sticks ;)
 
#7 ·
thanks for the comments guys really appreciate them.

motorcitymadmen, i made you a video you can be the judge if its "popping" and let me know i got buddy to rev it as high as she would go, you can kind of see the haze coming out from the truck and that was after idling for 30 minutes so im sure it was up to temp.
here is said video https://www.youtube.com/watch?v=5e5l-mil8TQ&feature=youtu.be
The truck isn't popping, and I wouldn't be overly concerned about that amount of haze.

common, i could care less about myself personally getting irritated or breathing the fumes. i just want this truck to run perfectly. haze coming out exhaust... not perfect.
Haze is normal to some extent. If you could measure opacity with some sort of instrument at the tailpipe under cruise conditions, it wouldn't register as "perfectly clear" even on the best running truck. You just don't notice it because it's not enough to be perceptible with the naked eye in a vibrating mirror with highway-speed wind dispersal. If the haze is actually visible in the mirror on the highway at operating temp, I would be looking for a cause.

4" straight pipe also save some bucks, check, does SS vs aluminized make a difference in sound or anything or just looks?
Sound will be the same. Corrosion resistance is the primary appeal to stainless systems.

so you are saying follow buddies post "timing in 40 minutes" just to check what my timing is but not to adjust? and if i do want to just get it adjusted take it into a shop and have them do it? (and be liable for the job).
Correct about the checking. It's an easy way to verify whether your timing is at stock or not. If it's not, you will either need to buy tools to check it, or pay a shop about the same amount to check it. If you see yourself changing the timing more than once and aren't intimidated at the prospect, it'll be cheaper to buy the tools and DIY.

im going to have to research into this pins you guys keep talking about, not familiar with timing yet. havent watched buddies "timing in 40 minutes" video yet maybe it will provide me with more insight.
It will. There's a timing pin on the back of the gearcase, under the IP, that engages with the cam gear when the engine is at TDC. There's another pin that engages with the IP shaft itself, and if your truck is at whatever stock timing the tag on the gearcase specifies, both will engage at the same time. These pins were incorporated so that if the pump had to be removed in the field, you can easily reference a "pretty close" timing point to get the engine running quickly. Now, this is NO SUBSTITUTE for properly setting timing with a dial indicator (or using the spill port method). And some will (and have) recommended even checking it with a dial indicator. But, IMO, if your timing pins engage at the same time, your timing is close enough to rule it out as a factor in your engine not running "right."

im assuming injectors not "poping" is a common issue with 12 valves, its got 270,000 kms(170.000 miles) on the ticker im sure its broken in enough and due for some big sticks ;)
It depends lots on how the truck was used and cared for. There's no set interval for how fast the pop pressure drops or when nozzles need replacement. Just have to pull them out and see what you got.
You could throw aftermarket sticks in and call it good, but be sure to research what will be best for your application if you decide to do that.
 
#8 ·
yah like its not to bad, but say i back up to my shop with the bay door open, by the time i turn off the truck walk into shop the shop is full of fumes. never expected it to be that bad, meh runs fine.

i guess your saying get my injectors tested, and get the timing checked. should i crank up the timing at all while they are in there? havent done to much research on it but since it seems i have some experience following this thread now, what would more degree of timing benefit me in the stock application?

with the injectors ill just have to get them tested i guess and then go from there on deciding what to do
 
#10 ·
Yeah, getting an enclosed space near the tailpipe is an effective way to get a headache. The more aggressive you get with fueling (bigger injectors, etc) the worse it typically gets. I still wouldn't expect a stock truck to be quite as bad as you describe, but each rig is different.

Simply having injectors that are popping low could easily explain the symptoms you describe. I've played with pop pressure a lot, and it seems that the higher you go the cleaner the truck runs, especially at or just off idle. Stock is 260 bar, I have my 5x12s at 290, and the haze is not any worse than my stock injectors were at 260. The first time I pulled my injectors, pops were down around 235-240 bar with a little over 270k miles on them. Bringing them back up to OEM pop pressure netted a noticeable difference in idle haze. Less of it, and didn't take as long to go away as the truck warmed up.

As far as timing, if you're going to pay a shop to check it, you might as well pay them a few more dollars to set it. 16* is a pretty universally accepted "safe" increase. It gives you some more power/fuel econ without putting your head gasket at risk, and isn't too much timing, which can cause problems trying to start a cold engine in the winter. But trial and error is the only way to find the sweet spot for your truck and needs, which is why you might consider getting the tools. They'll pay for themselves the first time you use them, and any time after that is a direct return on investment. Same with injectors, you can get a pop tester and shims for only a little more money than you can pay someone to test/adjust them.
 
#11 ·
I gave up long ago worrying about the haze. It doesn't matter what set of injectors that are in my truck, it hazes.

I do not think that it can be changed unless the truck is set back completely to factory specs.

It's a product of higher timing, added fueling, bigger chargers etc etc.....

You gotta check your timing.

Mine puffs at stop lights - but running on the highway, I don't see it - even at night in taillights.

Dauntless is giving you some choice info.
 
#15 ·
It's plugged in under 30* - first crank.

She was a little grumpy when it hit below zero.
 
#13 ·
alright guys thanks a lot for the help, guess i dont need to be to concerned about it for the time being, might be something to look into in the very near future.

ill have to research the procedures for pop testing and setting timing and see if i feel up for the procedures, anywhere you guys would start for learning how to properly check and set timing?

other things on my list are a fluidampr and checking my KDP even though i think it was already done/ fell into the oil pan ;). i want to get this truck running flawless and then start working on some go fast stuff. stock harmonic dampener is like a noodle on the end of the crank cant be having that.
 
#14 ·
Here's the Dodge TSB for checking/setting injection timing. The only thing I disagree with in here is that using the drop-valve method is a more accurate way of finding TDC than relying on the cam gear pin. Drop-valve method requires the use of a dial indicator with magnetic base to be accurate. Read through this, and if you decide you're up for it I'll walk you through drop-valve.

TSB 18-10-94 Rev. A

Larger, more informative timing charts (as well as charts in decimal inches) can be easily found through google.

Read through this to understand how the injector works:

Mopar1973Man's Dodge Cummins Articles - Injectors - How To Clean Your 12V Injectors

Search google and/or youtube for information on pop testing injectors. Adjustment of pop pressure on the 12v is done by disassembling the injector and adding or removing shims from underneath the spring that holds the pintle against the nozzle. I can give you sources for a pop tester and shims if you decide you're up for it.
 
#16 ·
Cool. I start plugging in when average nighttime lows hit low 40s or so. It's typical for us to see single digit daytime highs for a week or so, but it's abnormal to see negatives for more than a couple days. Good to know though, thanks for the info. Sounds pretty consistent with how my truck behaved last winter at 16*. It took a couple tries in single digits when I couldn't plug it in.
 
#17 ·
as far as your haze goes, I noticed a bit more idle haze when I threw in my 191 delivery valves. Im still chasing the AFC tuning around in circles trying to get just the right amount of fuel and drive ablity without the air police chasing me down....Ive gotten two, maybe three letters from California Air Resource Board saying ive been reported for excessive smoke.....I tend to believe its a matter of opinion but here in communist CA most peoples opinions suck. I would like to have a clean burning hard runner though
 
#19 ·
Up here where I am in Canada they don't much care about how much emissions you have :)

Maybe this will be a good indication of how much motor is running, in 5th gear I cruise at 75mph and 2200 rpm is this normal?
 
#21 ·
More so on if that's normal for a stock motor, timing, fueling what not.

No gauges yet that's next up on my ever increasing list of things to do.

I can't see any haze while I'm driving especially with the exhaust chopped off. Can't see a tailpipe right
 
#22 ·
I say check the timing. Mine was doing almost the same thing till I checked timming and it was at 8* up to 16.25 no more Haze
 
#23 ·
Hey dauntless,
Been super busy at work

Read through Pop testing and taking apart injectors, seems easy enough if you could send those sources my way that would be sweet.

Going to try and read through the timing link and info you provided tonight and see what I figure about that.
 
#24 ·
I also read through setting the timing seems easy enough, dodges quote 2-3 hours seems about right for the first time just to see how everything works but I figure once a guy knows exactly what the procedure is you could probably bang that job off in half an hour.

If you have time to walk me through the drop valve that would be great.

The TSB describes the special tools to set the timing from your guys experience which ones are recommended/needed, all of them or just a couple?
 
#25 ·
Drop Valve: http://www.cumminsforum.com/forum/94-98-engine/380108-drop-valve-method-find-tdc.html

Shims for adjusting pop pressure: FUEL INJECTOR SHIM KIT (ADJUST POP PRESSURE)

Pop tester: Quality Diesel Injector Nozzle Pop Pressure Test Tester | eBay

If you keep your eyes open on ebay you can score a slightly better deal than that one. I think I picked mine up for just over $100. You can also make your own out of a bottle jack, if you're so inclined. Any pop tester that 1) will connect to the 14mm male threads on the injector and 2) reads to at least 4500 psi will work.

For timing, you need a DV holder socket and the dial indicator adapter. Any two-hole gear puller will work as long as it'll physically fit where it needs to fit. A neat little low-pro deal came with the tool kit I ordered. Any dial indicator will work as long as you can thread an extension into the end.

This is the timing kit I got: Timing Tool Kit w DV Socket Cummins P7100 Fuel Pump Better Mileage More HP | eBay

Timing takes a while the first time you do it, but once you know which wrenches you need and what parts need to be removed, you can do it in about 45 minutes without rushing.
 
#26 ·
thanks a lot seems i have a few purchases to make as well as some more research into valve lash and what not and then get at it.

from what i understand with the drop valve method you are making two marks on the harmonic dampener to the same reference point on both sides of the valve spring moving and then using the dead center of these two marks as TDC and it should never change. once the dial indicator is removed instead of using the timing plug on the motor you are going off the mark you made? in"god prefers diesels" video he states that even the slightest movement in the crank can be a few degrees of timing now if your going off a mark you made on the balancer how far out would your mark have to be to make a difference in timing? .001" 1/8" i know my eyes are good for maybe 1/32" but much more then that would I be asking for trouble?

could the drop valve method be performed right as you are about to torque the timing gear for the pump back on after adjusting your timing. but this brings up an issue. you would need 2 dial indicators one to remain on the pump to ensure it does not move while rotating the engine. now this is all theoretical that the mark would need to be accurate to a very small error such as .001" on the harmonic balancer.

i have a 96 5 speed so without double checking the tag it should be stock at 14 degrees yes?.(where is this tag? on the crankcase cover?) now if the stock timing pin on the injection pump is out 3 degrees as "illflem" says he has seen then to correctly perform timing you are totally disregarding the timing pin on the pump? just TDC the motor and then zero your dial indicator on the pump and what ever you adjust from there is what you are changing your pumps timing too?

if some of these theories are correct the although "timing in 40 minutes" is a informative video it would not be accurate in all cases and could be leading some people to HG failure or worse with there motors.

now say my timing has slipped and is at 8 degrees im if going off TDC of the motor and adjusting it to say 16 degrees thinking it is at 14 degrees stock but really im adjusting it to 10 degrees timing. how would one verify how much timing is set stock?

"The timing pin on the injection pump is fine for adjusting valves but I've seen the pin off up to 3*.
Not good enough for setting the timing." this is a quote from illflem post im assuming he is talking about delivery valves when he says this?

having the truck for only a month now i still have a lot to learn about these motors but the more and more i look into it and the more you guys help the more im starting to realize why so many people love these 12 valve motors. being a diesel enthusiast my mind is spinning with ideas of the potential of these motors.

as i do some more searching on topics and information you guys have given me im sure i will come up with a few more questions but that is all for now thanks again.
 
#28 · (Edited)
thanks a lot seems i have a few purchases to make as well as some more research into valve lash and what not and then get at it.

from what i understand with the drop valve method you are making two marks on the harmonic dampener to the same reference point on both sides of the valve spring moving and then using the dead center of these two marks as TDC and it should never change. once the dial indicator is removed instead of using the timing plug on the motor you are going off the mark you made? in"god prefers diesels" video he states that even the slightest movement in the crank can be a few degrees of timing now if your going off a mark you made on the balancer how far out would your mark have to be to make a difference in timing? .001" 1/8" i know my eyes are good for maybe 1/32" but much more then that would I be asking for trouble?
You could figure out what each degree would work out to on the dampener surface by measuring circumference and dividing by 360. Without measuring, I'm thinking it's something like 9" in diameter, in which case each degree works out to .079" or just under 3/32.

On mine, I just made the initial marks lightly with a scribe tool, then filed a very small notch in the corner of the balancer. These reference marks were made off the wire on the bottom of the engine (because it's easier to see). Then I put it at TDC and made a reference mark that lined up perfectly with the trailing edge of the ESS so I could see the dial indicator and the mark at the same time. Your timing will only be as accurate as you decide you want it to be.

could the drop valve method be performed right as you are about to torque the timing gear for the pump back on after adjusting your timing. but this brings up an issue. you would need 2 dial indicators one to remain on the pump to ensure it does not move while rotating the engine. now this is all theoretical that the mark would need to be accurate to a very small error such as .001" on the harmonic balancer.
You need to have your marks made before you start trying to time it. The timing can slip during a gear torque, that's why you need to check it afterwards before you button it up. Tap the gear onto the taper and get it seated before you torque it. That, along with cleaning it properly, will prevent slips.

i have a 96 5 speed so without double checking the tag it should be stock at 14 degrees yes?.(where is this tag? on the crankcase cover?) now if the stock timing pin on the injection pump is out 3 degrees as "illflem" says he has seen then to correctly perform timing you are totally disregarding the timing pin on the pump? just TDC the motor and then zero your dial indicator on the pump and what ever you adjust from there is what you are changing your pumps timing too?
14 sounds right. The tag is on the drivers side of the gearcase, right in front of the IP. And yes, you are totally disregarding the timing pin on the pump, and for me the timing pin on the cam gear is only useful for initially finding TDC-ish when you go to find true TDC with drop-valve.

if some of these theories are correct the although "timing in 40 minutes" is a informative video it would not be accurate in all cases and could be leading some people to HG failure or worse with there motors.
The "timing in 40 minutes" video is a point of contention between backyard mechanics and tuning aficionados. IMO it is NOT the proper way to set timing, but it is useful in showing someone what the basic steps are. I think if you set your timing so far off that you're getting engine damage, you made a mistake that can't be blamed on the video.

now say my timing has slipped and is at 8 degrees im if going off TDC of the motor and adjusting it to say 16 degrees thinking it is at 14 degrees stock but really im adjusting it to 10 degrees timing. how would one verify how much timing is set stock?
Using the dial indicator will show you where the timing is, regardless of where it is. Plunger rise works out to an absolute measurement. Because of the camshaft profile in the IP, you can't accurately add timing by measuring rise on the plunger relative to where it was when the motor was at TDC. Look at a timing chart and compare the differences between numbers at one end of the chart and the other end of the chart and you'll see what I mean.

"The timing pin on the injection pump is fine for adjusting valves but I've seen the pin off up to 3*.
Not good enough for setting the timing." this is a quote from illflem post im assuming he is talking about delivery valves when he says this?
No, engine valves. You have to TDC the motor, set half the valves, then rotate it 360* and set the other half. There is no adjustment on DVs.

having the truck for only a month now i still have a lot to learn about these motors but the more and more i look into it and the more you guys help the more im starting to realize why so many people love these 12 valve motors. being a diesel enthusiast my mind is spinning with ideas of the potential of these motors.
I got on it the other day for the first time after bumping my timing to 20*. I was halfway through an intersection when I realized the guy coming at me was going way faster than he should have been, so I stabbed it. A split-second of turbo lag, then a hard shove into the seat and I felt my cheeks slide back on my face. I've been in plenty of rice rockets and hot rods that would do that, but a 7,000 lb truck? Yeah, that's cool. :thumbsup:

I don't believe Cummins sells timing tools. If they did, you'd pay enough to get two sets of the same tools off eBay. You might be able to find shims at your local Bosch pump shop, but sometimes those shops are d*cks and don't want the owner of the truck doing anything more than bringing parts in for them to work on.
 
#27 ·
one more thing dauntless does cummins sell a timing tool kit? and shims? being in canada shipping is always ridiculous to get stuff up here i have a cummins dealer in my backyard and in fact i like going in there. or would there prices be astronomical for parts like that?
 
#29 ·
I bought mine off the snap on truck. SP500 comes with the gear puller, DV socket, dial indicator and holder for around $230. I've already used it a dozen times messing with different timing. Worth it IMO.
 
#30 ·
did you ever get the timming set and did it solve your problem... hope it did would be great to know though so others know as well as several users have suggested it
 
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