1967 Thunderbird 390 engine lock...help

64ZCode,
Thanks. I was considering a strip of leather, and I like your suggestion also.

I hope Marvel Mystery Oil is as good and mysterious as everyone says it is.

I just purchased a bore site camera, and should have it tomorrow. I'm very anxious to see inside the cylinders on Saturday. I will share the images here.
 
Fordrodsteven,
This is the plan Fingers crossed and thank you.
Just make sure when you get to where you are going to try to start the car that the rear wheels are securely blocked or better yet.... off the ground. Just in case the transmission tries to go into gear to move the car when you least expect it. Also, I remember when starting the '66 I had.... I had to either have the steering wheel tilted to the right and / or hold the lever up to insure the safety start engaged and the starter would crank. (that is until I properly adjusted the shift linkage and safety start switch)
 
If it's locked up that tight I would pull the plugs, use a pin light to see if you can see rust inside the cylinders or take the heads off it. You could drop the oil pan and see if there's any rust on the bottom of cylinders or pistons. You could take off a crankshaft bearing cap one at a time and see if the pistons slide up and down in the cylinders one at a time.
 
If it's locked up that tight I would pull the plugs, use a pin light to see if you can see rust inside the cylinders or take the heads off it. You could drop the oil pan and see if there's any rust on the bottom of cylinders or pistons. You could take off a crankshaft bearing cap one at a time and see if the pistons slide up and down in the cylinders one at a time.
I don't think you can pull the pan unless you either lift the motor or turn the engine so the pan clears the crankshaft as its going backwards. It cannot go forward because of the cross member.
 
64ZCode,
Thanks. I was considering a strip of leather, and I like your suggestion also.

I hope Marvel Mystery Oil is as good and mysterious as everyone says it is.

I just purchased a bore site camera, and should have it tomorrow. I'm very anxious to see inside the cylinders on Saturday. I will share the images here.
I’ve never used MMO myself and it may be great stuff. A light penetrating oil will work best.
 
Hey One, that sounds good. Do you mix some in with the motor oil, and what proportions?

Doug
 
Hey One, that sounds good. Do you mix some in with the motor oil, and what proportions?

Doug
One quart of MMO with four quarts of motor oil. So basically the quart of MMO takes a quart of engine oil. My 1969 takes 5 quarts of oil. I guess it's the same with the 390? Easy enough. When you change oil you first add the entire bottle of MMO then add in the oil. On the bottle is the instructions for both adding to the fuel or the engine oil. Hell I use MMO in almost any gasoline engine I have. Even my riding mower which was running like shoot after sitting over the winter season.
 
I totally agree with one of the previous posts about trying to turn the engine in the opposite direction. Since you mention a 3 groove pulley that bolts on to the balancer, you could put some longer bolts into those boltholes. That would give you a place to put in a pry bar across those bolts (as close to the balancer as possible to keep from bending the bolts) and turn the engine in a reverse direction. Keep in mind these are relatively high compression engines, which means there is not much space on top of the pistons. Even a buildup of carbon could keep it from turning over completely. You mention the 1977 inspection. Forty-two years of sitting can do a lot of damage, especially if it wasn't prepped for storage (which it obviously wasn't). I wouldn't get my hopes up!
 
Hey MissouriFats, thanks for bringing up the bolt holes and pry bar approach. I was thinking about that but the nerve impulse hadn’t reached my fingers yet. Doug
 
Hey Gbird67, we’re dying of curiosity out here. Any updates?

Doug
 
If you can't turn it over by the crankshaft bolt. Which is usually 7/8 or 15/16 bolt not 11/16. I would start at the top and remove valve covers and make sure everything on top is ok. If it is I would drop the oil pan and loosen up or take the rod bearing caps off 1 by 1 to see if a piston is jammed or seized. You'll probably have to jack the engine up to get the oil pan off
 
Team,
Sorry I dropped off for a bit. I decided to pull the engine recently. Nothing we did would move the crank, so out it came. Not surprisingly it is all original inside and we pulled it completely apart. The bores appear to be ok, some of the rings are seized to the pistons and I am working to free them. Other than the seized rings, there are no other indicators why this engine would not move. Bearings looked ok, some had minor wear.
Plan is to clean up block, use the original components, and rebuild DIY. Soaking a ton of money into this car is not in the plans. I'll use crank, cam as is, new standard bearings and rings, etc. I may spring to have the heads looked at. I'm frankly stunned at the prices quoted to rebuild this engine to basic stock...no performance add ons....ridiculous!
To save time I'll probably take the block to be dipped, just trying to find the right shop.
One shop says they do a hot tank, non acid dip...but this will not get rid of rust. I think a dip that's does get rid or rust is preferred and interested in what the group thinks of these dips and DIY methods.
If there was a DIY way, I would try it. I've played around successfully with electrolysis on smaller parts with my 2-6 amp battery charger, but I'd need a huge tank and probably more amps to do the block. Also interested in what the group thinks about large scale electrolysis like this.
Regards,
Gbird67
 
Don't be really surprised on prices for a rebuild.Bead blasting the block clean, magnafluxing the block and heads. Resurfacing, new valve seats, guides etc... Going over the crank or over boring the cylinders for larger pistons. It's all factored in. A lot goes into a proper rebuild. I was quoted 6000 to rebuild my 460. You want it done right you are going to pay.
 
As an engine builder at a machine shop there really is no discernable difference in building a performance engine to a stock one as far as labor goes. Of course clearencing, porting and valve work are the exception. The foundation is checked, all measurements are taken the same way. But it is time consuming. If you have the know how to do the building most machine shops will work with you. As far as rust removal goes there are plenty of rust removers and neutralizes out there to clean up the block. If you can tackle the build let the machine shop do their part just remember to double check everything. Not everyone is as thorough as a concerned owner will be.
 
Hi Gbird67. Still, very odd you couldn't turn the engine when it was in the car.

But the cost of rebuild reminds me of an experience I had in 1973. I had a machine shop in Santa Barbara machine and assemble a short block for my Chevy 235 engine. Mr. Baker laid the crank and assembled the rest of the components into the block. The cost was a stunning $250 of my hard earned scratch. Seeing my distress, Mr. Baker said: "Son, women are one thing, but when a man has a good motor, he really has something!", and out came my checkbook.

Apologies to any members of the fairer sex reading this if it offends you. We're men, and we can change, if we have to, I guess.

Doug
 
The shop I spoke to offered a 'hot tank' but it does not sound like it would take care of rust. Does that mean they only use a strong detergent and hot water? Seems like an acid or other remover could be added to the bath also but I don't know. Can anyone shed light on this? Dies the rust removal follow the cleaning or is it all in one? I guess the rust is only an issue for older engines and not a normal thing for most shops, but I do not know for sure.
Thanks,
George
 
The shop I spoke to offered a 'hot tank' but it does not sound like it would take care of rust. Does that mean they only use a strong detergent and hot water? Seems like an acid or other remover could be added to the bath also but I don't know. Can anyone shed light on this? Dies the rust removal follow the cleaning or is it all in one? I guess the rust is only an issue for older engines and not a normal thing for most shops, but I do not know for sure.
Thanks,
George
Rust is only an issue on engines not taken care of, or something left neglected in a junkyard or out in a field. A properly taken care of motor shouldn’t really have a rust issue, and usually all that’s needed is a good cleaning in a hot tank or some degreaser. Then beadblasing the block clean.
 
Hot tank will eliminate rust and crud, your block will come out clean as a whistle.
 
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