2F Seized today while starting... (1 Viewer)

[muelbeedle]

A couple weeks ago I bought an FJ60 from a friend of mine who had just changed the head gasket on the 2F (207k miles). It was running just fine, I was working on getting it to pass CA smog (replaced cat this morning). It's had a slow oil leak at the plug, but I checked it before driving, it was about 3/4qt low, still above the "low" mark. I drove to O'reillys to get new oil plug gaskets and to warm up the new cat. In my driveway I killed the engine, then figured I'd see how it starts when warm (oil pressure was fine, temp was normal, everything seemed totally good except the oil leak). I cranked it once and it turned fine but didn't start.

I tried cranked it a second time and immediately (without spinning at all)... "THUNK"! And that was it. Every time now, it's just "thunk".

Put my jump start on-- still "thunk"

Checked oil again-- still above "low" line.

I pulled out all the spark plugs-- still "thunk".

I put it in 4th and tried to roll it-- "thunk" all locked up.

I pulled off the flywheel cover. Nothing looks weird.

I took a video of the starter/flywheel when starting. Starter pops out and engages the flywheel, then "thunk".

I took off the valve cover-- everything looks normal there.

Before I pull off the oil pan and start thinking about bent rods, stuck pistons or thrashed bearings, does anybody know of any common problems that might cause this? Flywheel getting caught on something? Distributor engaged funny? Parts that could shake loose somewhere and jam up your stuff? Anything easy?

It just seems really, really weird to me that it would seize like this... How could I have damaged the bottom end while nothing was even moving or anything!?

 

[Ian Macdonald]

Can you turn the engine (carefully) with a socket and wrench on the flywheel nut?

 

[Ian Macdonald]

I had starter issues recently. Took it apart and it was full of .... stuff. After cleaning and filing the contacts, eh voila!

 

[cruiserfj45]

Every thing short of the putting it in 4th gear and trying to rock it and turn over the engine, sounds like bad starter contacts. Put it in 4th gear and see if you can get the engine to move by pulling it with another vehicle. Look up replacing starter contacts. Very easy.

 

[cruiserfj45]

Where at on CA are you?

 

[muelbeedle]

@Ian Macdonald I don't have the right size socket yet, but will get one tomorrow and give it a shot.

@cruiserfj45 Thanks for the tip about the starter. I feel like it really shouldn't be too hard to bump over in 4th though, I've got all the plugs out and everything. I'll try pulling it with something if the breaker bar doesn't work. I'm in Fremont.

 

[cruiserfj45]

The closest guy who knows his stuff would be @orangefj45 in Stockton. His name is Georg and he owns Valley Hybrids, a Cruiser only shop. It should move pretty freely with the plugs removed in 4th and t case in high. You didn't by chance have the parking brake on when you were trying to rock it did you? It is a good idea when working on it to have it secure.

 

[LAMBCRUSHER]

46 mm socket...HTH

 

[muelbeedle]

Well, I finally got a chance to dig in and I found the problem-- It's crank bearing #4 with a gouge about 1/16" deep and equally wide. Crank spins freely by hand now that it's out... and the project begins! (Hopefully I can pull this off without taking out the engine)

 

[Ian Macdonald]

Good on ya for finding it. I was hoping for a simpler issue and fix for you.

 

[ozwallaby]

I don't think the bearing is the problem... there is something else.... the starter would just wipe that bearing out easily, especially with the plugs out.... there is something jamming the crank or cam/valve gear.... I know you say it turns freely with that bearing out, but I suspect something else is amiss.... look further I say....

 

[cederholm]

I agree with this. That bearing would make a mess but not seize the motor. Were you able to rock the motor before you pulled?

~ Carl

I don't think the bearing is the problem... there is something else.... the starter would just wipe that bearing out easily, especially with the plugs out.... there is something jamming the crank or cam/valve gear.... I know you say it turns freely with that bearing out, but I suspect something else is amiss.... look further I say....

 

[Output Shaft]

I'm agreeing with @ozwallaby.

The incidents leading up to not being able to start the engine are not congruent with it suddenly seizing. That little groove in the bearing wouldn't cause the crank to seize. (At least wouldn't think so).

Think about it:
The engine was running fine and was all hot and oiled. Then you turned it off... Then tried to start it again and no go. That's sounds like a starter issue to me.

I think the reason that the engine now can turn over a little easier now that the bearing has been removed is that 1/4 of the total bearing friction had been removed.

Of course I may be totally wrong about this, and perhaps the engine does have internal problems, but I'd rule out the starter first before going down the rabbit hole.. before unbolting another bearing cap.

Your starter is probably ancient anyway, and should be replaced regardless.

At least that's what I'm thinking.

 

[LAMBCRUSHER]

yeah the bearings in my old 3FE were far worse than that and it was running...

 

[Benjaman]

I would have pulled the plugs before the pan. Could be a dropped valve.

 

[muelbeedle]

The engine was really locked up right until the point that I cracked this one loose, this was the 4th crank bearing clamp that I loosened. The crank is pretty scored up as well. I haven't taken the crank out, but I imagine there's a metal chip that somehow got sucked in there... Finding where that piece of metal came from is the real problem, but at this point I'm thinking about a full on bottom end rebuild-- reground crank, crank/rod bearings, and might as well do the pistons and rings while I'm at it (the extra $500 is probably worth it if I don't have to take the oil pan off for another 200k).

I have to believe that if it were a dropped valve, I'd have some motion... Wouldn't it would back up a little and then impact the valve at a certain spot... but it was locked solid? A buddy of mine brought over a video scope too and we checked out the cylinder walls, which are all looking nice and clean. The only thing I haven't really looked at is the timing gears, but I'd think they'd probably still give me trouble even after taking the bearing out.

Definitely going to rebuild or replace that starter though, sounds like a good chance it's bad news and it'll be cheap insurance. Also going to replace the crank seal there for sure too.

 

[Dynosoar]

With the knowledge that the head gasket was just changed I would of just pulled the spark plugs. I bet one cylinder went hydraulic ( filled with water). You probably have a cracked head, this is fairly common on later 2f heads. That little smudge on the bearing, while not good would not have been the source of the problem.

Dyno

 

[LAMBCRUSHER]

okay. you've decided you're going to rebuild the bottom half...you should read the engine manual 3 times before committing to any purchases or services. read Jim Cs how not to rebuild a 2F and the best 2F threads all the way thru...many details and thus pitfalls if not all procedures are followed. know exactly the work you want done and exactly the methods required to do so- the machinist will defer to their own logic if not provided the blue prints. I'll say this. if that little scratch caused all of this, then it is crazy to think how many of them are out there just about to seize up, still running fine. alot of work to go thru to find a bad starter or a clutch issue. you might believe a dropped valve would allow you some rotation, but I believe that bearing is not the problem.

 

[muelbeedle]

@Dynosoar - Pulling out the spark plugs was the first thing I did. Hydro lock would've been nice. How would a cracked head cause it to lock up? Wouldn't that cause loss of compression?

@LAMBCRUSHER Thanks for the tip about Jim C. I've got a hard copy of the manual and already started devouring it... but the photos in here are super tasty How not to build the 2F

 

[Dynosoar]

Crack in head could fill a cylinder with water. If you pulled the plugs than my theory is out the window.