Seized engine

christine

New Member
I'm not a mechanic, just mechanically inclined n learning what I need. So bare w me. I just need to know if I'm headed down right path. 2000 lesabre, GM 3800. One owner car(my grandma). It was parked on a farm outdoors for 3+years till I got it. Aunt said they drove it 25 miles to be serviced before dropping it off, but for whatever reason they didn't change oil. Drove it 60 miles w no issue before my husband did so. The oil filter basically had to be peeled off to accomplish. He drove it less than 10 miles before coming home w it making some horrible noise, shut it off and has since refused to start. Assumed starter but do to his illness it sat for 8 more months. I replaced starter, still won't turn over. Just a solid thunk when the keys turned. Cannot turn crank by hand. My assumption is that it's seized due to rust but.... it tried pretty hard once and then just the thunk after. PB blaster in plug wells got one little whisper of attempt. So..... more blaster n more time or do I just shut the hood n call time of death
 
Hi Christine, welcome to the forum !

Those engines (GM 3800) are known to develop coolant leaks in the intake manifold and in some cases can leak into the cylinders and cause a hydraulic lock. If just one cylinder has enough coolant, the engine cannot compress a liquid and therefore the starter cannot turn the engine over.

Try removing all the spark plugs and then see if you can turn the engine over. If it does turn over it will also be puking coolant out of the spark plug holes.

I just hope you have not bent any of the connecting rods, it can happen even with only the starter turning the engine over.

Let us know what you find.

.
 
as a first test step, in logical step by step engine forensics
ID pull all the spark plugs and make certain the battery is fully charged, and read the dip stick, is it full and does the oil look black, or is it over full and oil looks like a cup of coffee with cream, is there rust on the dip stick???
, if none of the spark plugs are obviously sitting in a cylinder full of coolant from a cracked head or leaking head gasket..
.ID start the forensics by putting a squirt about 4 to 6 table spoons of 50%/50% diesel fuel and marvel mystery oil in each spark plug hole and let it sit over night, this lube fluid bath will loosen rust and aluminum corrosion on the engine bore to piston surfaces, then, without replacing the spark plugs , and after a full 12-15 hours, ID hit the starter, yes if it kicks / spins over ,there will be a mess of sprayed oil, (having a few old beach towels over the spark plug holes helps reduce the potential mess)and yes it will be very noisy, but it will show the crank/piston assembly's free to spin, if it does not, pull the valve covers and take and post pictures, and drain the oil , then pour the old oil through a section of window screening, to catch any sludge or metallic bearing fragments, and take pictures,
we may learn a few things from the pictures
if it does spin easily and there's just old black oil, in the oil pan, try to measure the volume that drains, then, replace the oil and oil filter and do a compression test yeah, the possibility exists that the engine has a spun connecting rod bearing or main bearing, or bent rod or defective valve train, components, a logical process can find the cause!
there's nothing all that difficult to do, it will require some basic mechanical tools and skills and getting your hands dirty, but you also have the potential to learn many new skills, and yeah,
obviously having a buddy with previous experience and a few tools helps a great deal

read the links and sub links










 
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as a first test step, in logical step by step engine forensics
ID pull all the spark plugs and make certain the battery is fully charged, and read the dip stick, is it full and does the oil look black, or is it over full and oil looks like a cup of coffee with cream, is there rust on the dip stick???
, if none of the spark plugs are obviously sitting in a cylinder full of coolant from a cracked head or leaking head gasket..
.ID start the forensics by putting a squirt about 4 to 6 table spoons of 50%/50% diesel fuel and marvel mystery oil in each spark plug hole and let it sit over night, this lube fluid bath will loosen rust and aluminum corrosion on the engine bore to piston surfaces, then, without replacing the spark plugs , and after a full 12-15 hours, ID hit the starter, yes if it kicks / spins over ,there will be a mess of sprayed oil, (having a few old beach towels over the spark plug holes helps reduce the potential mess)and yes it will be very noisy, but it will show the crank/piston assembly's free to spin, if it does not, pull the valve covers and take and post pictures, and drain the oil , then pour the old oil through a section of window screening, to catch any sludge or metallic bearing fragments, and take pictures,
we may learn a few things from the pictures
if it does spin easily and there's just old black oil, in the oil pan, try to measure the volume that drains, then, replace the oil and oil filter and do a compression test yeah, the possibility exists that the engine has a spun connecting rod bearing or main bearing, or bent rod or defective valve train, components, a logical process can find the cause!
there's nothing all that difficult to do, it will require some basic mechanical tools and skills and getting your hands dirty, but you also have the potential to learn many new skills, and yeah,
obviously having a buddy with previous experience and a few tools helps a great deal

read the links and sub links







Being a girl I approach it slightly different. Every guy I know thinks he knows and is almost always wrong. My advantage is I already know I know nothing. And I don't touch it till I've checked n dbl checked. I've changed water pump, alternator and found a sneaky coolant leak on my 3.1 last yr. The oil in it has about 12 miles on it so its clean. Full, and dipstick looks good. I drained n flushed the coolant tank n radiator when I was cleaning up the engine compartment so I could see. I did pull the top 3 plugs but have them just sitting in wells to keep the grime around them from falling in. As I said, it's been sitting outdoors in nebrasksa farm country for 3+ years n exposed to God knows what
as a first test step, in logical step by step engine forensics
ID pull all the spark plugs and make certain the battery is fully charged, and read the dip stick, is it full and does the oil look black, or is it over full and oil looks like a cup of coffee with cream, is there rust on the dip stick???
, if none of the spark plugs are obviously sitting in a cylinder full of coolant from a cracked head or leaking head gasket..
.ID start the forensics by putting a squirt about 4 to 6 table spoons of 50%/50% diesel fuel and marvel mystery oil in each spark plug hole and let it sit over night, this lube fluid bath will loosen rust and aluminum corrosion on the engine bore to piston surfaces, then, without replacing the spark plugs , and after a full 12-15 hours, ID hit the starter, yes if it kicks / spins over ,there will be a mess of sprayed oil, (having a few old beach towels over the spark plug holes helps reduce the potential mess)and yes it will be very noisy, but it will show the crank/piston assembly's free to spin, if it does not, pull the valve covers and take and post pictures, and drain the oil , then pour the old oil through a section of window screening, to catch any sludge or metallic bearing fragments, and take pictures,
we may learn a few things from the pictures
if it does spin easily and there's just old black oil, in the oil pan, try to measure the volume that drains, then, replace the oil and oil filter and do a compression test yeah, the possibility exists that the engine has a spun connecting rod bearing or main bearing, or bent rod or defective valve train, components, a logical process can find the cause!
there's nothing all that difficult to do, it will require some basic mechanical tools and skills and getting your hands dirty, but you also have the potential to learn many new skills, and yeah,
obviously having a buddy with previous experience and a few tools helps a great deal

read the links and sub links









 
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Im certainly not talking down too you or anyone else, many of the members are very skilled/knowledgeable,
Im just trying to point out areas that will require checking, keep in mind people will read the thread months or years later, and I need to point out things THEY may not think of,
even if you or most more experienced readers do know about many things, that you know or have already done , and obvious checked those items
if the engine will not turn over easily with a breaker bar , or with the starter,,make sure its in neutral, and as mentioned, pull the remaining spark plugs and fill all the
cylinders partially as previously mentioned, let the engine with the MMO/diesel mix sit over night,
index.php

and try to spin the engine, after its set and soaked in the oil in the bores for 12-15 hours
theres a logical process and verifying all cylinders are free of coolant and not hydraulically locked is part of that forensic process,
Id also point out the next step is verifying the valves are not bent, or locked up in the valve guides,
even a single cylinder, partly full of coolant will bind the engine
 
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I in no way feel talked down to. Msg boards like this n YouTube have been my only teacher along w Chilton n the Gmail parts warehouse for identifying things. The "boys" I refer to are the ones I encounter I'm person and the reason I have decided to do it myself w yalls help. And so far we have a 100% success rate. I'm grateful for the help and the thoroughness for readers later. This is the first time I've had to post a question thanks to that. I'm shopping for things now and will return with how things are going
 
the more detailed info and clear pictures you post,
the faster we can locate and cure any potential problems found
 
Take out all the plugs and dump a ounce or so of Marvel Mystery Oil down each cylinder and let soak for a while then if you get it moving keep working it while adding more MMO each time and keep soaking and adding MMO it will take a while and don't rush it if it frees up change oil with 1 Qt. of MMO added to oil. Then when it starts let it idle for a while until warmed up and it quits smoking then I would do another oil change with 1 Qt. of MMO added to the oil ad change plugs and at this point if it runs ok do a complete tune up with new plug wires and cap and rotor Good Luck
 
Drove it 60 miles w no issue before my husband did so.
Assumed starter but do to his illness it sat for 8 more months.
He drove it less than 10 miles before coming home w it making some horrible noise, shut it off and has since refused to start.
The oil in it has about 12 miles on it so its clean.

If it didn't rust to the point of locking the engine in 3 years, it hard to believe that 8 months would do it. Unless there is something that I'm not understanding or the conditions were very different about the 8 months. I guess it's possible thou.

I know those engines are notorious for the plenum leaking from corrosion. I had to replace mine 1998 Buick Park Avenue. But only careful diagnosis will reveal the real problem.
 
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