I have a L2900 that usually runs good no smoke, after using it for about an hour and shutting off I went back to start and it won't turn over. The flywheel tries to turn but asks like there is too much compression holding it back. I let it sit for a couple of days and it cranked but smoked for a while then quit smoking and sounded fine. I noticed that there were bubbles coming up in coolant overflow tank when cold and most of the water was gone from the radiator and overflow was full. I checked oil and there is no antifreeze in it, could this be a blown head gasket? How can I know for sure?
Head Gasket?
- Thread starter jody
- Start date
STOP!!! trying to start it until you know for sure or you could end up bending a conrod if water is on top of the piston and the engine locks.
Try removing the injectors or heater plugs the spin the engine to see if any water squirts out but keep eyes away as it can come out with a force.
Do you have access to compression /leak down tester or radiator pressure tester?
Try removing the injectors or heater plugs the spin the engine to see if any water squirts out but keep eyes away as it can come out with a force.
Do you have access to compression /leak down tester or radiator pressure tester?
Agreed it sounds like the head gasket popped and you're leaking coolant into one of the cylinders. That smoke you saw was coolant in the cylinder burning off. Sounds like you lucked out and didn't bend a connection rod when you started it after it locked the first time. The starter doesn't have enough force to bend a rod but combustion does. Do what B7100 said and crank it with the glow plugs out, you'll probably get a jet of coolant out of one or two cylinders. If you do then it's time for surgery.
Thanks for the advice, I am going today to get a radiator pressure tester, but I do know that the pressure builds quickly in the radiator, almost as soon as you start it. I do smell antifreeze in the "smoke" as it runs. After I pull the glow plugs and turn it over would it hurt anything to run it long enough to load onto a trailer?
If you smell coolant in the exhaust then you've definitely got a head gasket problem (or a cracked head but that's unlikely).
Does that machine have a temperature gauge? A leaking head gasket can cause a vapor lock in the cooling system and prevent circulation (don't ask me how I know that). Also I can't imagine coolant in the cylinder does anything good for lubrication of the cylinder walls so I would avoid loading the motor heavily and keep the run time to a minimum. Turn it over without the plugs in to blow the water out, slap them back in quickly and you should be ok for a short run. Oh and crack the radiator cap and top the system back off manually. The vacuum that allows the expansion tank to refill the cooling system when it cools off can't form with a big leak. Also also once you've refilled it and cranked it let it sit for 30 seconds or so and then crank it again and see if theres a lot of water coming out. If the leak is too big I wouldn't try it. I have gotten away with it before though.
Does that machine have a temperature gauge? A leaking head gasket can cause a vapor lock in the cooling system and prevent circulation (don't ask me how I know that). Also I can't imagine coolant in the cylinder does anything good for lubrication of the cylinder walls so I would avoid loading the motor heavily and keep the run time to a minimum. Turn it over without the plugs in to blow the water out, slap them back in quickly and you should be ok for a short run. Oh and crack the radiator cap and top the system back off manually. The vacuum that allows the expansion tank to refill the cooling system when it cools off can't form with a big leak. Also also once you've refilled it and cranked it let it sit for 30 seconds or so and then crank it again and see if theres a lot of water coming out. If the leak is too big I wouldn't try it. I have gotten away with it before though.
Last edited: