Motor seized. What to do???

[NoMoneyZ]

Alright, long story short. Truck was sitting for around 10 years. Started to get into it. Rebuilt the carb, checked out all the fluids, tested starter, threw in a battery. Turn the key and clunk... try again, clunk... Hmmm... So now a decide to try to get in there and turn the motor with a big o' wrench. Well I tried and tried and no success. So with that I am assuming that the motor is frozen. I am now left to wonder what to do with it. It has a lot of sentimental value so I don't want to junk it but what are my engine options? I am looking for motors with a HP range of atleast 160-200 if possible. Any help is appreciated.

[J.C_620]

what i would try before i went and bought another engine is to roll to wall-mart and get some marvel mystery oil come back home and take out all the spark plugs and fill the cylinders full then put the plugs back in then take the valve cover off and pour some over the top of the cam and rockers the reinstall the valve cover and maybe pour some in the crank case also then forget about it for 2-3 days then come back take the plugs out and try to turn it

[Guest kamakazi620]

This might take a few days,But first off pull the plugs and dump some marvel mystery oil in the cylinders let it sit for a day then try to turn the motor over with your breaker bar,move it back and forth DO NOT try to force it very fast just gently with some pressure,if it does not break lose repeat.

[J.C_620]

yeah i suggest you do as kamakazi :ninja:suggested..... yeah yeah do as he said it will probably work has for me many times:hyper:

[NoMoneyZ]

Wow this forum is quick. Thanks. I'll pick some up tomorrow and give it a shot. Thanks again.

[datsunfish]

Do you know the history of the motor? It would take a bit of moisture and time to lock it up. If it does free up and that was the cause chances are it will have some major pitting that will cause problems with blow by. It could be a warped head that can also cause that. The cam can bind up. I would pull the head and inspect it. If its a rusty mess do the oil thing and sand it down to see the extent of pitting,if major I would either pull it and rebuild it or search for a new motor. Stock L series of any sort will never be over 110 hp without some serious mods so for the big hp expect to spend some$$ or retrofit a modern motor in it.

[datzenmike]

If it was stored outside with the hood off or carb uncovered just forget it. If it was protected, squirt some WD-40 in the plug holes and try in a few days. Use the starter. As long as water doesn't get in the cylinder they should brake loose. I've pulled motors that have sat for a dozen years and there is lots of oil trapped on the bearing surfaces. Even one that was full of water in the crank case and it still turned over! If the cylinder gets wet... forget it.

[NoMoneyZ]

Well I guess that much HP isn't necessary since this is a small truck. Well this truck originally had a L20b but it was switched out about 15 years ago with a L18 pullout. We didn't do the swap just had a shop do it. The truck ended up sitting for the last 10 years or so. I live in the high desert so it doesn't get too wet out here. Ran just fine when parked besides the carb acting up. The hood was always on and it had an aircleaner on it the whole time.

[shocker6969]

i had the same problem in one of my trucks and all i did was filled each cylinder with WD-40 i ended up using 2 cans the left it for twp weeks with the plugs out and then pulled it with a truck down the road at about 20kms and kept dropping the clutch untill the motor brock loose i left the hood off so when she broke u could see the fluid come out

[Guest kamakazi620]

^^^^And I thought I was a Redneck^^^^You also said it had a carb problem,Do you think maybe a cylinder is full of gas?? check for hydrolock as well,Just throwin' it out there i know its been sitting for 10+ years and the gas should have evaporated/leaked past piston rings,did you change the oil???

[garryk6]

I had my grandfathers old 1962 Cadillac Fleetwood with the Caddy 390. Trailered it from Redding CA to San Diego, and the engine was locked up on it too. Redding is pretty dry, but it had sat for over 10 years after being driven to the spot it sat in. I did the Marvel Mystery oil trick, but let is set for litterally months, and with it being an automatic, I didn;t have the luxury of dropping the clutch.

One thing, dont use the crankshaft bolt to do the turning, as it is not made for that type of torque. I tried a breaker bar and the teeth on the flywheel to no avail. So I charged up the battery, and then I hooked up my jumper cable to a 454 Suburban with the engine revved on the "burb" and then hit the key on the caddy. the first two times it just went clunk. Remember cylinders are full of Marvel Mystery oil and the plugs are out, also the fan belt was removed due to the alternator being froze up. The third time of the starter, and it went "rrrrg" and moved, hit it a few more times with time inbetween for the batteries t ocharge from the "burb" and it started to turn over really free. Then we freed the alternator, replaced the fan belt, put fresh gas and plugs, fresh points, cap and rotor, and two cranks and she lived.... Lots of smoke for a few minutes... but she lived. then i had to fill up the tranny with fluid, and rebuild the brakes (the initial reason for it being parked). The guy I sold it to, has yet to rebuild the engine and drives it every weekend in San Diego as his primary family car!!! He did replace the valve stem seals as they were leaking and causing a smoking condition, but the rings actually reseated, and the car ran great. This was about 8-9 years ago.

Good Luck!!!

Garry K in Kodiak, AK

[NoMoneyZ]

Well it seems the marvel mystery oil is the thing to try so I will get that and see what happens. I tried the crank bolt before just to see if I could break it loose and all It did was tighten more and loosen the bolt. I'll post up after I do the oil trick and let everyone know what happens.

[1974datsun]

what i did with my truck is pulled it behind another truck and popped the clutch, that freeed my motor up, if its a automatic idk what you could do except use marvel magic oil or what ever that oil is, it works wonders

[nukeday]

Another vote for MMO. I've actually drained the oil and left the drain plug out, then put an ounce or more in each of the spark plug holes and just...waited. Check it every day or so, and if you have some red MMO coming out of the drain plug, at least some of it has made it by the rings. As datzenmike has said though, if the cylinder walls have gotten wet, freeing it up doesn't really mean anything.

 

Have you checked the clutch? Make sure it's not in gear when you go to spin the engine, either by hand or by starter.

 

Let us know what happens, good luck. :)

[MicroMachinery]

My Dad gave me his old 521 a few years back, and it had been sitting in his shop for 15yrs prior to that. It's here in Oregon, where the air is pretty wet, but it was atleast covered, and had the air cleaner on. A little ATF in the cylinders to soak, along with priming the system via a modified bug-sprayer, and I let it sit. Came back, hooked up the battery, and it cranked right over. Make sure to prime the entire system, not just inside the cylinders.. your bearings are likely pretty dry too. Good luck!

[Guest kamakazi620]

^^ like he said ATF does work to free up stuck motors^^ but make sure to oil up the motor after it "breaks free"

[herculesinwyoming]

thats what i did on mine, it sat for close to 20 years, marvel mystery oil is darn close to tranyy fluid, but i oiled in the spark plug holes and let it sit 2 days, and it fired right up.

[FH620]

I have a 77 ford hiboy, same thing the motor sat and was frozen, I filled the cylinders with half trans fluid and half with paint thinner and let is sit for a week drained the oil and sprayed p b blaster in the cylinders. then worked the engine back and forth a little bit more each time untill it would tun compleatly over easily then with the plugs still out used the starter, it blew about a handfull or two of rusty chunks out, i have put about 5k on it so far and it runs great and no smoke

[NoMoneyZ]

Well I tried the Mystery oil, and no luck. Motor is frozen solid. Getting it towed in to have it tore down and rebuilt next week. Thanks for the suggestions.

[MicroMachinery]

I guess someone didn't like my advice...?

 

Anyhow, when you get it torn down, let me know what you find. I'm dealing with a similar situation with a wagon that's sat for 15 years. Thanks!

[banzai510(hainz)]

olddatsuns.com the tech section

yes you can do this!!!!!!!!!

[TrevDaddy]

I recently bought a L20 block and rot. assembly that was sitting outside. It was running a few months ago, and all it took to make it free up was one night with PB blaster in the cylinders. I'll have to bore it to get the rust off, but i could see bare metal just rubbing on them with my finger a lil bit. Thats promising if you ask me!