CAT 320Dl C6.4 Heavy Start

[Kaushil Solanki]

Hello guys,
I have a Caterpillar 320DL, the machine ran and started very well when cold (after rest), but after working for hours and heating up when the machine was turned off and back on it would be heavy starting, suddenly one day it would not start at all. I gave it to an local ET guy to have a look at it and it came out that the Injection Nozzles were bad.
I replaced the Injection Nozzles (all 6 nozzles have the same serial number) , the previous nozzles that I removed had all different serial numbers.
After replacing, the machine ran well for almost 3 days and started incurring the same problem again. so I contacted an ET guy from the local CAT dealer. Who came, checked and told me that the Control box and the transfer fuel pump were supposed to be changed. After changing these, the machines runs well, however the heavy start problem still exists after working for hours.
The CAT ET guy told me that the Injection Nozzles should not be having the same serial number, this is causing the machine to heavy start.
I already have incurred a lot of costs it would be really helpful if I got an idea on what exactly the problem is and what needs to be done.

 

[Chrisso]

Did you buy these injectors aftermarket or from Cat? When replacing them on a C6.4 you'll need to use the s/n off the injector to download an injector trim file, then use ET to install it, repeating for each injector. The only numbers that should be the same on all injectors are the part numbers.

 

[Chrisso]

Also I'm guessing this is a common rail C6.4... Post your s/n for more accurate info.

 

[Kaushil Solanki]

Hello Chrisso
Yes it is common Rail engine. We had downloaded the file and performed ET when installing these nozzles.
I purchased the injector nozzles from a local spare part shop (Not CAT) but the nozzles came with Caterpillar packing.
This has also left me confused if the nozzles are original CAT or I have been conned.
I have uploaded my machine details and the nozzles (same S/N) that I purchased.

 

[BigWrench55]

It is not uncommon to buy reman injectors and have one or two return too much fuel. What is the rail pressure when this happens vs the desired rail pressure. Has the return flow been measured? Has the rail been inspected for a groove being cut do to over relief conditions or a faulty relief valve? Has the relief valve and pressure sensor been replaced? Has the low pressure fuel system been checked for proper pressure and flow? Were the injecor cups replaced? There is a lot that can go wrong in this system and all these things need to be checked out to know what the problem is.