seized 390

[anotherbigeater]

You guys have a great community here with a lot of helpful, informed opinions. Sorry I haven't introduced myself ('69 F250 camper special, 390 c6 2wd) on the appropriate forum but I wanted to take some good pics and finish just one more project.....and then this happens. I'll give you a quick summary, driving truck 10 mi. at 65 mph- pulled off highway and drove a mile when truck starts to make a loud ticking sound which is then accompanied by a deeper knock as soon as i give it gas to pull into a parking lot (also accompanied by strong vibration thru truck), didn't drive it more than 200 yards in this condition, came back 5 hrs later and motor only cranked a quarter turn one time and then became immobile, removed all spark plugs to see if it was a hydrostatic lock- but it wasn't, also pulled all belts off-but still nothing, towed it home and have not yet looked at it. The factory oil pressure gauge looked like it was slightly lower than normal but I haven't been driving this truck much so I wasn't sure if it was normal variation(usually is pegged straight down middle but was on low side 3/16 an inch). I am guessing their was some form of major crank/connecting arm failure. So the questions at this point are (1.) What would be the easiest way to diagnose extent of damage(maybe it could be fixed without engine removal)? (2.) Are their any later model engines that would bolt up to my c6 that might be a good swap(maybe something a little less "cold hearted"). Thanks for the help, I will answer any questions/give details to clarify if needed.

[bumpside]

I think you might try to turn the engine backwards by hand, using a socket and breaker bar. Hopefully the bolt on the crank will not turn and the crankshaft will. If the crank turns backwards, I would guess you broke a rod. if it will not I guess you siezed the engine. Either way you will need to pull the engine to fix it properly. My

[Banjo]

if you couldn't roll it over by hand with the plugs all out, sounds pretty bad. You might could find a way to remove oil pan with engine in truck to see what broke? I've done that before, but not on 390.

[anotherbigeater]

Took a look at it this afternoon, tied to turn the crank without any plugs and it wouldn't go in either direction. The oil pan doesn't look like it has enough room to clear the crossmember without pulling the engine. The engine is definitely going to have to come out. I guess i'll find out what caused all the commotion soon enough. My curiosity is to much to send it to the wrecking yard without seeing the cause and making a shadetree diagnosis. I'm just surprised at how suddenly it took a dump, running fine for months, oil looked great, then boom outta nowhere. Iv'e thrown a rod before (on a slant-six) and it was hardly a surprise when it went. Anyway i'll report back when I get a more complete picture.

[sideoilerfe]

No other style engine will bolt up to your tranny. FE engines have their own bolt pattern.

[bumpside]

I have one other far fetched idea. The torque converter or the flex plate could have broken and might be wedged inside the bellhousing. It is a long shot, but it is worth looking into. Good luck on your task at hand

[fordman]

if your close i have a good running 360 to get rid of. i also have a 352 that could be put back with a new carb and exhaust and be a runner. or it could be used for parts to replace whatever you need.

[anotherbigeater]

Thanks for the offer fordman but your just a wee bit to far away, i'm in Stockton,Ca. And fomocoguy your absolutely right, that wrecking yard talk was premature, I was just getting a little down over the whole thing and talking reactionary I will be checking craigslist for an FE and begin teardown soon. Anyone got ideas on the price range of a short-block?

[fordman]

hey i know you can find one out there easily enough.

[saidyene]

You can pull the oil pan without pulling the engine. I just did it on my 360 a few months back. You have to pull the nuts off the mounts then raise it about 6 in. That should give you enough room to drop the pan. It saved me a bunch of work when i replaced my oil pump. I hope you figure out what happened. I know I hate not knowing what broke even if im just going to replace it.

[fordman]

what do you mean? will the engine move either way when you try and turn it? if it won't . you are going to have to tear it apart or replace the engine. only fe engine blocks will bolt up to your trans. if it is locked up the best way to rebuild it is to pull the engine. it would probably be hard to try and do an inframe rebuild on a locked up engine. if you need more info just ask.

[kf6wxj]

Thanks for the offer fordman but your just a wee bit to far away, i'm in Stockton,Ca. And fomocoguy your absolutely right, that wrecking yard talk was premature, I was just getting a little down over the whole thing and talking reactionary I will be checking craigslist for an FE and begin teardown soon. Anyone got ideas on the price range of a short-block?

I hope Im not stepping on anyone shoes(My Apologies) but if you get another FE with accessories Ide like to place a claim for the throttle linkage if its a 4 bbl. Im in Sacramento. Bill

PS I can be reached [via private message]