89 Blue Bird 5.9 Gen 1 Cummins, Blown Head gasket

[Apacheglen]

Hi,
I knew the bus had some issues, but found that the head gasket is leaking between 4 and 5 on the exhaust side.
Does anyone have experience changing the head gasket, or have a manual for the cummins? This is a flat nose bus, and access to the motor is great up top, but will be a challenge removing all the stuff required to remove the head.

Any advice is appreciated.

Thanks,
Glen

[kamoo]

Would the busses be affected by the dowel pin problem? I had thought it was only a problem with the rotary pumps and most busses have the inline?
Another thing everyone with the 5.9 and air brakes should check is the rear air compressor bolts. They tend to come loose and without this rear support it will crack the timing chain housing which is not a real simple cheap repair either.

[Apacheglen]

Long Story,
The head was cracked too, so I found a 12 head with 7mm injector holes. The head was almost new (had receipts to prove it), with about 1 hour of use.
My block was OK, just under service limits, about .005". I did not have a way to shave the block, but the new head was nearly perfect. I pulled a valve, and did a seat inspection found it to excellent. Put the head back together...
The motor is back together, and runs well. I think I have all the air out of the cooling system.. The motor has great oil pressure about 35psi at idle, temp 170, and 60psi at 2300rpm.

The head seems OK, no leaks, the coolant doesn't pressurize.

There is one thing wrong, the engine warning light and buzzer comes on after about 5 minutes. Pressure, temp, and alt voltage are all excellent. The radiator has no pressure to speak of, the heaters in the rear work, so I beleive there is adequate coolant supply. It's about a 50/50 mix.

Any suggestions?
Thanks,

I'll have to get the the dowel inspection soon... but after the engine buzzer.