The Stovebolt Site Forums The Shop Area Engine Shop seized engine - diesel (non-Stovebolt)

I know its not Stovebolt related but it involves a 4 cylinder Toyota diesel. The engine has been working fine and yesterday for some unknown reason it would not turn over. Its a 24 volt system and the batteries are good. I pulled the starter thinking maybe the Bendix was jammed in the ring gear. On the front pulley is a large bolt and even with a long flex handle and socket the engine will not budge. We have pulled the glow plugs and the ignitors to relieve the compression and nothing. Its almost as if something is wedged in there to prevent it turning. I am thinmking of pulling the timing gear cover to see if there are any broken gears jamming the engine from turning.
Looking at the shop manual it indicates possibly a main bearing, a broken con rod or wrist pin. However I think that if that were the case the engine would still turn with all the torque we have applied manually to the front pulley. But its frozen stiff and this happened just about overnight.
Appreciate any ideas.

Bill,

When you put your cheater bar on the large bolt on the front pulley, can you get it to wiggle even the slightest bit when you do a push/pull drill. If something really is frozen, but it will wiggle a tiny bit back and forth, it would indicate that it isn't a piston or a bearing but more along the lines of a auxillary drive, gear or pump....something that has backlash associated with it.

If it ran fine last night but is frozen now, there might be something rotten in Denmark! This wouldn't be a typical scenario, as you probably know.

Stuart

Stuart
Nothing wiggles at all. Tight as a drum. It even rocks the engine on its mounts. Under the timing cover besides the cam and crank gear is another idler gear and a gear set up for timing the injectors. Was thinking maybe a tooth chipped and its wedging itself to cause this lock up. Although with the effort put on the pry bar one would think it could still be turned.
The truck was undercover overnight so we cannot think that someone tampered with it.
One think I forgot to mention in my post was on recent start ups there was a squeal which almost sounded like sheet metal rubbing. it lasted a few seconds and then wth the engine idling it went away. Could that be a main bearing, i don't know.
Bill

Bill,

What a mystery. If you are able to really oink on the long cheater bar and absolutely nothing moves my thought would one of the major rotating pieces, or a piston.

Is it possible to get a better advantage with a bar on the ring gear somehow? Sometimes a frozen spot can be popped loose with a super effort and unless major material has smeared and transferred, the engine will 'self heal' so to speak.

Toyota's are tough little farts....keep us posted!

Stuart

There is little room to swing a big lever on the ring gear. I think what I'll do is drop the pan and look for broken metal and then if I can reach the con rods I'll try to wiggle them to see if one is broken. I presume that if all are good there would be very little play on them. I am not at the point where I want to pull the main caps.
Sadly this whole exercise is being done for a neighbor who thought he knew everything and would not listen to experience even though he asked for help.

If it seized after it cooled, it is likely that a main bearing failed. When it cooled it could have welded itself solid.

If it doesn't budge with a cheater, pull the pan.

It only ran for a few minutes during a test and then was shut down. Hardly had time to get the operating temps up. Will pull the pan.

Pulled the pan and # 1 con rod cap was bone dry while the others were oil soaked. Pieces of bearing in the pan. Told him to pull the end cap off the con rod and then see if the piston would move. It did and the crank will turn.
Now the bearing is a holy mess and it looks like scars in the end cap as well. I am concerned that the crank may be scarred as well and as I have yet to see the upper half of the con rod I cannot tell how it looks.
I can't offer him any more advice but would not want to see him replace that con bearing until he finds what caused it to fail. It is frustrating watching him (I won't touch anything anymore) as his work area is hard packed sand and the idea of keeping garbage out of the oil holes, bearings or whatever falls on deaf ears. And he knows all the answers!!

Bill,

Interesting. How nice to find the answer so fast. I'll bet this fellow has some redeeming qualities, maybe not automotive repair though. You're a good man for lending all the help you have under the circumstances.

Stuart

Stuart
He is a neighbour and a good one. But its frustrating giving him advice and then having him ignore it. I guess it will be a while before that old diesel chugs through the neighbourhood. Feel bad for the guy in a way.
Bill

The crankshaft will be ruined, no doubt about it. You're wasting your time trying to help out, so quit beating yourself up about it. There's probably a clogged oil passage to that rod journal that's going to trash a new bearing as soon as he tries to run the engine, if it will turn at all with a scored crankshaft.
Jerry