Heavy Equipment Repair Questions? Ask an Expert Now.
I have a Cat engine 3406E. I had a problem - there is water in the coolant system. What should I do now? Please help.
Hi. Thanks for using JA!
I would drain the oil and pressurize the cooling system so you can see where the coolant is coming from. It could be a liner or a head gasket or possibly a water pump. Let me know if you need more help.
I am wrong, not water in the coolant system; but diesel in my coolant system.
Oh I see. If you have diesel fuel in your cooling system, your engine has had an injector cup O ring failure. This problem is not hard at all to get fixed. The injectors will need to be removed and the cooling system drained. There is a special Cat tool needed to remove and install the cups. You most likely only have 1 or 2 cups leaking but I would recommend replacing all of the injector cup O rings. If you don't, another O ring may fail soon after and you'll have to do this again.
Please let me know if you need more help.
Could you let me know why it caused the injector cup o rings to fail? Just because of it was too old or the coolant needed to be replaced regularly or all the injectors were not working properly in other? And do I have to change all the injector o rings? If I do what should I buy - the right things and please give the parts # too please.
The O rings will fail when the engine gets a lot of miles on it. It is also possible that if the coolant conditioner in the antifreeze is too high, it can cause the O rings to fail. I can get you the part numbers you need, it will take me a little while but I will be back soon.
Yes sir, I am waiting for your parts number that I need to solve my problems.
Thanks for the information.
The tool that you need to remove and install the injector cups is 9U-6891.
Each cup has 3 different O rings. The part numbers are:
9 X-7 4 3 0
1 6 6-2 9 0 3
1 6 6-2 9 0 4
If you plan on doing them all, you will need 6 of each.