2005 T800 with a C15 acert. Injector harness issues at the connector on the injector. They seem to be arcing across from one side of the connector to the other and burning up the harness. This is the second one we have installed and I having these issues. Does anybody know where to get a harness that is not a factory defect like these recent batch seem to be? Or does anybody have any suggestions on how to remedy this?
Are you in a wet environment ? Logging ? You might look at high temp dielectric grease to seal the connectors. Stuff used on spark plug boots might work well.
It's the connection to the injector that is going bad.
The areas circled in red are the problems. Soon as it gets warm the isolating material between the two metallic connectors seems to get hot and melt and they come close together and arc out as noticed by the red circle on the right and the missing material in it.
Over tightening the nuts will also fracture that plastic and shorten its life considerably. Don't ask me how I know
Order a 3408 or 3412 harness as it has the Deutsch ends one on end but made of the old reliable wire and ends. Cut off the deutsch ends and then add in your own quality wire with high strand count to make the rest of the harness. Been fighting the same issues (more so your other thread with wires breaking) for over a year. This will bridge the gap till Cat can get proper harness again. They are well aware of it and scrambling but till all stock is flushed and new stuff produced this is what we have
Ok, I will give that a try. Thank you for your help.
Is this true? It would be the worst ******** ever if they know they have a bad patch and will not get good ones until they sell the defective ones. That can not be good for future sales.
The harnesses that have issues are in new engines, remain engines, on dealer shelves, etc so it takes time to flush them out. Not saying Cat is standing by waiting for 10,000 warranty claims but the dealer Hallback bought from didn’t know ? What else do you do when they have no others to sell ? Tell customers their C15 is down till further notice ? After our 5th bad one (tried on-highway ones with jake plugs just to try but also failed) we had to make our own solution. Not ideal but also not rocket science what we need to build. Also it takes claims to roll in before they sense a problem, verify, go to the supplier, get the harness build changed etc. Due to the fact it’s not going to cause contingent damage but just a miss and a code typically I bet this would be a pull stock off dealer shelves (when new ones ready) and for the rest an “after failure” type of warranty Again this is all my just my opinion so take it as just that.
These kinds of things also happen on the part counter. If the customer supplies the part number, the person on the parts end of the phone call just plugs it in to the computer and checks for stock. There might be a note on the part but if it is in stock that's where the matter ends. It isn't until the parts warranty arguments come up that the alarm bells start to ring.
Out of interest what Part Number are you ordering, or what Part Number is the dealer supplying..? If the two are different please give both numbers.
321-4323 & 321-4324
+1 on Vetech's comment reference over-tightening the nuts that secure the connector to the injector. Or buy the 257-4183 repair harness kit and splice it into the existing harness.....
Word of caution - been there done that - With the splices installed they failed faster than the original harness. The wires are so hard they break at the splice. Tried solder. Broke at the solder joint. Tried marine grade eyelets straight to the injector - those latest better but did break off in time as well. Again this is for the bad wires more than the strange issue you had with the ends That’s why the 3408/3412 harness are older stock and slower moving so they are the old good wires and ends
Why cant people read the book regarding torque specs. Overtightening these connectors is a no-no. Same as any injector connection, Cat, Cummins, or Detroit. I have seen studs that were "hourglassed" to the point of needing to have the injector replaced. Really?
Just because Haulback or his mechanic is a logger isn't an indication that they overtightened or installed anything incorrectly. He asked a question and big ben provided a pretty viable answer to a situation that he had seen before. I've had pretty similar experiences with most every brand and type of product.
BB, I agree with you and you are correct that the wire is the issue not so much the ends. The wire is like some aluminum type crap that just does not hold up at all, any vibration kills it. They shouldn't even be selling those even be selling those to customers as when that thing fails it can wipe out a cylinder very easily. And as far as all the comments on over torquing, just because I'm a logger doesn't mean I am an idiot.
Those Part Numbers are specific to C15 engines MXS & NXS-prefix. Without practical experience I'm not sure why, could be the wire length or the terminations at the outer end. The grade of wire used for the harness is related to the fact that the voltage fired through it to the injector is something in the region of 120V (not a misprint) IIRC. From experience with a similar type of harness on HEUI engines in machines the harnesses were also very sensitive to being correctly routed and supported with the correct ty-wraps. Too narrow of a ty-wrap and the harness would not live. Back to torqueing, below is the spec from the manual for information to the OP. I'm not saying that he is over-tightening the nut, simply throwing out there what the spec is - approximately 2 ft.lbs. This could be achieved with nothing more than a socket on the end of a screwdriver handle. "Position harness assembly (7) in position on the electronic unit injector. Tighten the cap nuts to a torque of 2.5 ± 0.25 N·m (22 ± 2 lb in). "
Thanks Nice! I ordered two used takeoffs today. One 3406E & a 6nz. Hopefully I can make one work.
Glad to help. If you need anything else shout out.
I appreciate everyone's advice & experience in this.
Next question, when the injector studs are hourglassed and shot, who can I send the injectors to to get new caps put on or do I just have to spend 600 bucks for a new injector from Caterpillar? The Caps are only $15.
It appears as though replacement (Reman or new) injectors may be the only option. I have 2 part numbers, one is a 155-4066 Solenoid, the other a 148-6841 Housing. Both are part of the fuel injector assembly for your engine but I can't see an illustration anywhere for either of them. That being the case I wouldn't guarantee that either one is what you're looking for, or even whether or not your local Cat dealer would be able to sell one to you. It looks like the studs on the top are 164-5017. Again, highly unlikely that you will be able to buy them separately.
Evidently the upper cap with the studs is shimmed for each injector. According to Oregon fuel injector they say they just send their back to Caterpillar. I am getting very tired of caterpillar and all their proprietary parts and pieces since Caterpillar quality that we grew up with and loved in the 70s and 80s is no longer.