Cat 279C Alternator is not charging

[Matt Matsuzaka]

Hello I am new to this Forum.

I bought 2011 Cat 279C and I am having a few problems serial MBT02200.

First the alternator died I took it in and have it tested it was died. So I bought a new one installed it and its not charging. I checked the voltage on the on the signal wire with the key on engine off and I’m getting 8V. Still no charging I checked all fuses everything is good. I did read on here something about a main breaker, but I cannot find one on my machine. Maybe I just not looking in the right place. I did replace the battery with a new cat batter because the old one was over 3 years old. The yellow light with the ! is flashing in the cab.


The second problem is that if I fill my radiator full it dumps in the overflow on the door and runs out on the ground. Is this a bad radiator cap? Or is there supposed to be a one-way valve to keep the coolant from running down to the overflow bottle?

Thank you for you help.

 

[92U 3406]

Typically when they overflow the bottle its a blown head gasket. Very common on those engines. Changed many heads and head gaskets on those.

 

[Matt Matsuzaka]

Well that could be fun is the gasket set I acn get form Cat? It dosnt look to bad to do or am I wrong?

Should I just rebuild the whole engine? it has 4000 hours on it

Is there a service manual I can buy for this machine?

Thank you for your help.

 

[Vetech63]

Well that could be fun is the gasket set I acn get form Cat? It dosnt look to bad to do or am I wrong?

Should I just rebuild the whole engine? it has 4000 hours on it

Is there a service manual I can buy for this machine?

Thank you for your help.

Just the head gasket but check the head for cracks. Definitely get a service manual before breaking it apart. If you have the tooling and can follow instructions you should be able to handle it yourself

 

[Matt Matsuzaka]

Do you have a recommendation for a place to get a service manual I see there are a lot places out there.

 

[92U 3406]

Everything should be available from the dealer. Unfortunately I have yet to see one where the head didn't have to be ground or replaced. Its almost always erroded where the leak is. Never seen block errosion thankfully.

I found that coating both sides of the gasket with Permatex High-Tac Spray-A-Gasket before install and torque seems to increase longevity. Definitely want to go around the pattern and re-check all the bolts until they stop moving at the final torque. Have had to go around 3 or 4 times.

If its your first one, expect it to take about 12 hours if you're somewhat mechanically inclined.

 

[AllDodge]

I checked the voltage on the on the signal wire with the key on engine off and I’m getting 8V. Still no charging

If the battery reads more then 8V, then you have some corrosion or a broken wire. If the ALT wire is not connected to the battery directly (normally connects at the starter post) then as soon as the motor fires up it can blow the ALT again