Engine Seems locked up after mist(maybe light smoke) from near raditor

[dpepes]

I have a 1967 Ford 4000, it started fine and ran for about 5 to 10 minutes, then had a light mist (or could be smoke) from front near radiator/water pump. Engine began making knocking sound, shut engine down and check oil (not milky) and opened radiator to check for coolant, it was a little foamy so I topped off radiator with about 1/2 gallon of water. Tractor started and ran but still made a bad knocking sound, no smoke what so ever from exhaust. I parked it and came back next day to try to figure out problem. Tractor would not turn over, starter would hit hard but not spin engine. Also hooked another tractor to it, put it in gear and it just slid, tires would not turn. Engine would not spin when pulled in gear.

I am trying to figure out if this is a crankshaft that is seized or what might have caused this to happen so quickly. Engine has always run like a top with no smoking.

Any ideas??

 

[davesl708]

Possible blown head gasket. Coolant filled the cylinder and it is hydro locked. Is this gas or diesel? in either case pull the plugs or fuel injectors to find the flooded cylinder.

 

[dpepes]

Diesel, I will try pulling fuel injectors when I get a chance. Thanks!!!

 

[whis]

maybe it dropped a valve, if you can't turn it over by hand (wrench on crankshaft) after pulling injectors, don't try pull starting good way to bend a rod

 

[Redneck in training]

You can also pull glow plugs. Whatever is easier to do.

 

[dpepes]

Thanks folks for the input! I may have a chance of actually getting this thing back running without a complete overhaul, it would be hard to put $2500 into a $4000 tractor. The tractor is 1 year younger than I am, and I really would like to keep it going. My 2012 Mahindra is nice but I have a soft spot for older iron.

I will let you know what I find when I pull the injectors.

 

[DJ54]

If it would happen to be the case that it hydro locked, I hope you didn't bend the piston rod on that cylinder, by trying to pull start it. It has been known to happen.

 

[Farmerford]

I agree with Davesl708. Leak occurred in headgasket between a cylinder and coolant passage. The combustion gasses passing through the leak pressurized the cooling system well above the 7-14psi design pressure, blowing vapor out the overflow pipe in the radiator fill neck. The fact that the coolant was foamy and 2 quarts low is consistent with a head gasket leak. It might have been going on for quite a while and just now got bad enough for the blowoff to be noticeable.

When it sat overnight coolant flowed through the leak and filled the cylinder, preventing the piston from moving up on the compression stroke.

Two things you said are inconsistent with this diagnosis. First, you said there was no smoke from the exhaust. Water in a diesel cylinder produces white smoke when it is turned to steam by the heat of
combustion. I guess there could be so much water that the fuel in that cylinder would not fire, though I have never experienced that.

Second, you said the engine knocked badly. That is not normally caused by a leaking head gasket.

However, I suppose there could have been just enough water in the cylinder when it was running to occupy most of the combustion space with the piston at the top. That would immerse the injector tip in water and prevent the ignition of the fuel and perhaps either the ingition miss or attempted minor compression of the water/air accounts for the knock.

The easiest way to learn about a bent connecting rod is to check the height of each piston at TDC when you pull the head. If one is lower than the others it is a sure sign of a bent rod.

Good luck and keep us posted on what you find.

 

[redman135]

If you do the checks as above and draw a blank then you may have run a big or main end bearing. My mf135 rapidly developed a loud knock so I shutdown. Because it was shut down early it just cost a set of bearing shells, rings, and seals to repair it. Good luck.

 

[dpepes]

Finally got 20 mins to pull injectors. Engine turns over fine with injectors pulled so I guess it was hydrolocked. Anything I need to do engine until I can get head gasket replaced, and any other items that would be good to do while replacing?? It may be a couple of months til I have time.