Hi everyone, new to the forum and the backhoe world. Purchased a 580 CK extandahoe (unknown year since there's no engine SN) few weeks ago and it needed few little things fixed, but for a 50 yo machine is to be expected. The main problem initially was that the radiator cap was bubbling when the engine was running. And not only when it was cold but also when it was hot. The valve cover vent was venting steam looking gas so i figured the head gasket was blown. Two weeks ago i pulled the cylinder head checked it for warpage, cleaned everything and put if back together. Looked for any damage or cracks in the sleeves but no issues there. Followed the manual and put everything back together and tried to start it last night. However, the radiator coolant bubling is still there. Any ideas or advice? Thank you, Vincent
Sorry to hear that. It could be a leak in the head, or the head gasket not sealing again. I'd run it for a while with water in the radiator so glycol doesn't get into the oil if it is leaking. See what it does, keep steaming and bubbling or work itself out. Only other thing I can think of to try, is remove the injectors and use compressed air with a compression tester to see if you can replicate the bubbling in the radiator, and narrow it down to one cylinder. Then try it with the piston at TDC and BDC to see if it changes.
Or just pull one injector at a time and look for the bubbles to stop, it'll be a little loud but it should show you the source in a hurry.
Removed the cyl head yesterday. However, before that I took the injectors out and used compressed air to blow in each cylinder. It started bubbling on cyl #2. Once the head was out i looked real closely to the block and sleeve and the cyl head but i couldnt see any cracks/damage. There's a coolant passage that had some corrosion on it, i'm inclined to believe the gasket is not sealing very well and its blowing by to the coolant passage. not sure yet. Taking the head tomorrow to a machine shop.