Help!! I'm afraid my engine has seized

[norm02]

Hey guys,

I'm in the process of rebuilding my '66 Roadster (full story in the "chat" section) and I'm afraid the motor has seized. The truck ran fine the last time I drove it but that was about 15 years ago. It has sat in my lake house garage since and I recently brought it home and it's now in my shop.

I pulled the spark plugs out and squirted some Marvel Mystery oil in each of the cylinders and I let it sit for a day. Syphoned the oil out and then tried to turn the motor over by hand with a fairly large socket wrench. I couldn't get it to budge so I tried to turn it over with the starter and it still won't turn over. I can see the fan blade slightly move but that's it.

I'm not entirely sure what else to do other than fill the cylinders back up and let it soak for another few days. I'm not looking forward to pulling the head off the motor and I'm hoping it doesn't come to that. Any ideas would be greatly appreciated!

 

[Steve83]

Use penetrating oil - not MMO. You should have used MMO when you stored it.

But even if it frees up enough to rotate, I wouldn't expect it to make good compression after those rust spots go through a few heat cycles; maybe not even that long.

You have NO details for the truck in your profile or signature - you should fix that. I assume by your singular use of "head" that it's a straight 6 engine.

 

[langester]

I had an inboard 4 cyl boat motor do this. I used pb blaster and marvel mystery oil and after a few days I finally got it to break loose. Hopefully yours will free up too. Good luck!

 

[D.R.Y.]

5Sounds crazy but a old truck mechanic told me if it is really rusted up and stuck, pour some vinger down the plug holes and let sit. (I use it to clear original bolts that are rust) Tried it once on a frozen hemi and it worked.

 

[half cab]

Diesel fuel works pretty good for this also after several days of soaking.

 

[okie4570]

5Sounds crazy but a old truck mechanic told me if it is really rusted up and stuck, pour some vinger down the plug holes and let sit. (I use it to clear original bolts that are rust) Tried it once on a frozen hemi and it worked.

Haven't tried it on a seized engine, but vinegar is what I clean my steel traps with....... it's magic.

 

[bmc69]

5Sounds crazy but a old truck mechanic told me if it is really rusted up and stuck, pour some vinger down the plug holes and let sit. (I use it to clear original bolts that are rust) Tried it once on a frozen hemi and it worked.

That..or Coca Cola. Works amazingly well, though not quickly. I'll pour it in and let is sit for a month. But you can't use that trick after you've already put penetrating oil in the cylinders.

 

[norm02]

Use penetrating oil - not MMO. You should have used MMO when you stored it.

But even if it frees up enough to rotate, I wouldn't expect it to make good compression after those rust spots go through a few heat cycles; maybe not even that long.

You have NO details for the truck in your profile or signature - you should fix that. I assume by your singular use of "head" that it's a straight 6 engine.

I guess we'll see if it frees up after sitting more last night as I'm going to try it with a larger breaker bar tomorrow and see what happens. You assumed correctly regarding it being a 6 cylinder and I've updated my signature. Thanks!

 

[Broncobowsher]

Wasn't the magic rust eater ATF + Acetone?

Sounds like you have stuck rings. The tiny twitch of the fan shows the crank wants to move. you are just teased with the clearance of the bearings.

Vinegar in the cylinders is pouring acid into the engine. Very last ditch. If that doesn't work right away it will just sit there and eat metal. Iron rings and bore with aluminum pistons, dis-similar metals in acid. Electrolysis erosion. It will either work, or it will make the engine into scrap. Viable if working on junk but not something I would recommend if you really want to save the original engine.

 

[dave67fd]

Can I also assume you tried turning it over with the plugs out? also disconnect all your accesories (remove your belts) so your just turning the crank to eliminate any other holdups. Good luck

 

[Slowleak]

ATF with Acetone has worked wonders for me. I put everything I could find on a stuck distributor once. Then I read the attached article and tried the miracle mix overnight. The next morning I could turn that distributor like it was never even stuck....
http://www.jalopyjournal.com/forum/threads/penetrating-oil-showdown.350800/

 

[norm02]

Can I also assume you tried turning it over with the plugs out? also disconnect all your accesories (remove your belts) so your just turning the crank to eliminate any other holdups. Good luck

Plugs were out but the belt was still on. I can slip the fan with the belt not moving so not sure how much resistance that would be causing. The being said, I'm going to remove the belt and the starter tonight and try it again in tomorrow. Hopefully the starter or something else is holding it up.

Perhaps I'm wrong, but I find it hard to believe that it's seized up when it ran fine last time I drove it. Yes, that was 15+ years ago, but its been sitting in a garage in the meantime.

I know I should have prepped it better but I never intended on this much time going by before I would start playing with it again. That's how life goes I guess but I'm not ready to throw the towel in on it yet. We'll see what happens tomorrow..

 

[norm02]

Wasn't the magic rust eater ATF + Acetone?

Sounds like you have stuck rings. The tiny twitch of the fan shows the crank wants to move. you are just teased with the clearance of the bearings.

Vinegar in the cylinders is pouring acid into the engine. Very last ditch. If that doesn't work right away it will just sit there and eat metal. Iron rings and bore with aluminum pistons, dis-similar metals in acid. Electrolysis erosion. It will either work, or it will make the engine into scrap. Viable if working on junk but not something I would recommend if you really want to save the original engine.

I'm out on pouring vinegar into the cylinders if that could potentially ruin it or make things worse. If it won't turn over with everything disconnected then I'll pull the cylinder head off to get a better look at what's going on.

 

[bmc69]

Wasn't the magic rust eater ATF + Acetone?

ATF mixed with acetone won in a test comparison against an array of commercial "penetrating oils" hands down.(including the famous Kroil, which did come in second. PB Blaster was last, btw..but I digress)

But it does not "eat" rust; it's still a penetrating lubricant.

...Coca Cola actually does dissolve rust, in effect. The phosphoric acid in Coke is part of what makes it work like that...

 

[Steve83]

...I'm going to try it with a larger breaker bar tomorrow and see what happens.

I wouldn't do that. The HB bolt is NOT suited to breaking a stuck crankshaft - you'll break the bolt first. The best thing to use is the starter since that system is designed to put a LOT of torque into the crankshaft. Make sure the battery is fully-charged, and all the heavy cables' terminals are clean & tight.

.

If you need to spin it the other way, or if the starter isn't strong enough to break it forward, use a prybar against the flywheel's ring gear teeth & the bellhousing. That gives you the best mechanical advantage to turn the crank, which will do the least damage to everything else.


I wouldn't put anything else into the engine, but especially NOT carbonated soft drinks. We all know what sugar in the gasoline can do to an engine, so don't pour it directly into the cylinders unless you're about to rebuild the whole engine anyway. If you just have to use snake-oil, use sparkling water - it has the carbonic acid, but no sugar. Vinegar is another acid, and I wouldn't use any acid in a honed cylinder. Penetrating oil is specifically engineered for this purpose & application, and it's not rare or prohibitively expensive.

 

[Dave K.]

Kroil is great stuff, helped break free a motor I picked up which has been sitting outside for a long time...

 

[bmc69]

I wouldn't put anything else into the engine, but especially NOT carbonated soft drinks.

In't it funny that mechanics have been using Coke to successfully free stuck engines for close to 100 years.



The old guy that first educated me about that "trick" was a former gas/service station owner (in the 1930s-60s) and had a large collection of cars that he had restored, dating from 1908 through 1930 or so.

 

[SHX669]

Have you also checked to see if the tranny isn't " stuck in gear"?
I'd also pull the valve cover and dump Krolls or penetrating oil onto the valves,ifters,valve springs, rocker arm shaft --

 

[norm02]

Have you also checked to see if the tranny isn't " stuck in gear"?
I'd also pull the valve cover and dump Krolls or penetrating oil onto the valves,ifters,valve springs, rocker arm shaft --

Yes, transmission is in neutral and I pushed it forward to make sure it would roll. I also pushed the clutch in and went through all of the gears and then went back to neutral.

 

[Steve83]

In't it funny that mechanics have been using Coke to successfully free stuck engines for close to 100 years.

Hilarious.




It's even funnier that Coke wasn't invented until the 40s, and probably didn't get used as a break-free agent in engines by its inventor or any early customers. Reminds me of that Abraham Lincoln quote about internet statistics...

But I bet if you search hard enough, you can find that someone somewhere at some time has used Mercury, baking soda, and explosives to free stuck engines. That doesn't mean any of them are the best for this particular engine.

I also pushed the clutch in and went through all of the gears and then went back to neutral.

In that case, put it in the highest gear, get it rolling, & pop the clutch. You can do that rolling backward, too (always in the highest forward gear).