I have a d6r series 2 with the c 9 engine with about 10k hrs on it. it has had the injectors and pump replaced in the past year by cat per previous owner. when it idles it sounds like one cylinder has a slight miss. as soon as you increase rpms the slightest, it goes away. has plenty of power and sounds great under a load. I have just purchased this unit and don't know if this is normal for the hours on it ect.
I don't think it should sound like a misfire. Get cat to put ET on it and do an injector cutout test and look for a bad injector. Have seen injectors work good as you load them up then start missing as you drop the load off of them. Later Bob
I wonder if the trim codes or the injector flash files were installed when they replaced the injectors. Each injector delivers a different amount of fuel , they use the trim codes or flash files to balance them all out. This would only show up at idle and it would be fairly small amount of difference. Injector cutout test as Bob/Ont says is the best idea to find which cylinder is weak.
do you have a infrared therometer ? if so shoot the ehaust ports to find the dead hole, cold start and then start shooting temps, it'll show you which cyl is limping. i dont know much about injector trim but i too would say its a injector problem...... does it go away or get worse after the engine is hot ? ......to the pro's just for my curiosity is there any way that a tight valve could cause the problem? edit: mobiltech, why wouldnt they want all injectors flowing the same fuel ? i've never heard of this...... each cyl should carry the same HP shouldnt it ? pj
PJ, the idea is that all injectors flow exactly the same amount of fuel, but manufacturing differences beteween injectors means that they don't. So the purpose of the Trim Code is to modify the amount of fuel injected into each cylinder so that they are all pulling exactly the same amount of fuel.
P J the trim codes are numbers dedicated to individual injectors and perform minor adjustments to achieve equal fuel delivery. Flash files set engine speeds and power. Later Bob
Effectively what happens during manufacture is that each injector goes on a test rig and its fuel output is measured. As a result of that measurement and how much it differs from the "standard" a Trim Code is etched on the plunger or on the solenoid housing. Then when the injector is installed in an engine the same code is entered into the ECM for the cylinder in which the injector is installed. For a 6-cylinder engine the ECM will have 6 Trim Codes in it, one for each cylinder 1-6.
Thanks. That's what I meant to say but I guess I worded it wrong. I find the trim codes make a noticeable difference on truck engines because they have less parasitic load and deliver less fuel at idle speeds than a crawler engine would.
Using the temp gun is a good idea too but you have to allow for an increase in manifold temp as you move to the center of the turbo. For example number one cyl might be 150 f number 2 would be about 170f and number 3 would be 190f . Each cylinder adds to the temp of the next due to the flow towards the turbo.
The C9 just doesn't sound like a 3306 engine when they idling after startup.They run rougher and remind me a little like the old 2-cylinder John Deere,but not as bad.If it doesn't have a noticable bad miss it is more the nature of the C9.You might still have issues ,but this is the norm for mine,which has plenty of power. Having both the 3306 and C9 motors i notice that the C9 has a faster respond time when you decel.They seem snapper i guess is the word i want to use.I still like the 3306 engine when everything is tuned right.My C9 is better on fuel by at least 2 gallon and hour from what i have checked.Good luck
thanks for the info, this is my first crawler with a c9. everything in the past from 6c,6r to 7g has had 3306. that's great to know its going to get better fuel economy, am used to 10 gal/hr out of the old 7g. Do they start good cold? this one showed up on a lowboy yesterday with outside temp of about 10 degrees. it cranked fine but would not hit or put out any white smoke. after plugging it in and charging batteries it finally took off. it did not seem to respond well to starter fluid which I guess your not supposed to use cause of preheater I found out later.
i gotchya now, i was thinking you meant that they wanted each pulling different hp and i couldnt figure it out lol. i always pair up the cyl's when shooting temp, 1&6. 2&5. 3&4. etc. a little temp diff isnt a big deal that i've found but you'll know when you find the bad one, before temp guns we used to pour water on manifold and see which one was the last to evaporate it off,...... now i have a thermal imaging camera and WOW how easy it is to find a dead or weak hole you can even without looking at exhaust manifold. however i do still use a $50 temp gun a lot too tho, im a litttle less nervous about dropping it in a fan lol. pj
No they don't like cold weather.They have a ethyl bottle that is mounted on the rear right side of the motor.I haven't put one on mine yet,but haven't worked in the colder weather here enough to need it.On mine the grid heater doesn't come on after it get down to the teens.I'm guessing that is when the ecm tells it to shot the starter fluid in to start.Think this has been discussed down a few post about starting when cold. As far as fuel use mine is very good,but others have said different.You can go a good 12 hours with out filling it up on a long hard day pushing dirt.Luck you have a engine heater if that is what you pluged in.Thinking that is a summer job here for mine.Keep the oil changed and clean ,and you will have less issues.
thanks that's sounds like good info. As far as oil and change interval what is your recommendation. I have been running 30w in the old 7g and changing every 250 hrs or so. Should I go ahead and buy the cat oil or is any 15w 40 like delvac or dello 400 alright to use. cat claims you can run their oil for 500 hrs. if you do it within 3 month period. maybe it would be better to go with non cat oil and change it more often.
The c9 in the d6r has a unique sound, especially on decel, " bark bark ", there should be plugs above computer for different weight oils, 250 hours is good, drain fuel tank regularly, good luck, overworked.
For automatic ether injection at low ambient temperatures the ether is controlled by the engine electronics. Factory setting is "Disabled" IIRC, to enable it requires Cat ET hooked up to the machine. I answered your oil question on another thread but you don't need Cat-branded oil. Any major brand (Mobil, Conoco, Shell, etc) CI-4 or CJ-4 SAE15W/40 oil will work fine in that engine. Be anal about changing the oil and filter right at 250 hour intervals. If your machine does not work so many hours then change the oil based on time, I think it's 3 months. 500-hour oil change intervals IMHO are for machines that work 24/7 and pretty much never go cold between one oil change and the next. If that's not the way you are operating your tractor I'd stick to 250-hour oil changes. The additional oil you use will be waaaaaaaay cheaper than a set of injectors and a HEUI pump.