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Discussion Starter #1 (Edited)
It sat for a couple of weeks. (on vacation, normally it's my daily runner)
Went to start it, the starter ran noticeably faster than usual, but engine wouldn't run.
Charged the battery for the halibut, no help.
Towed it to shop.
While replacing the timing belt, the mechanic couldn't move the engine to TDC.
He showed me -- he can move it one way (backwards?) but going the other way (clockwise?) even with a breaker bar, it stops.

Any ideas?
Would the timing belt break if the engine seized?
Does it crank faster because of a broken timing belt?

There were no odd noises or symptoms before this failure (I often drive with the radio off, at least for part of the trip.)
I change the oil myself every 3k and check it once in between.
It doesn't leak or burn any oil.
250k miles 2WD automatic 4-door.

Thanks!
 

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Yes, fast cranking is a clue to a broken timing belt since there is no compression to impede it.
Whether or not a seized engine would break the belt is a moot point since there's likely some serious internal damage. Then trying to force it with a breaker bar is totally inept possibly causing more damage.
In any case it doesn't look good for it being your daily driver for a while.
 

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While replacing the timing belt, the mechanic couldn't move the engine to TDC.
He showed me -- he can move it one way (backwards?) but going the other way (clockwise?) even with a breaker bar, it stops.
Me now thinks he has the new timing belt off by a mile so no valves are open at the critical instances. Removing the plugs should allow it to turn by hand if that's the problem.
 

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Discussion Starter #5
Me now thinks he has the new timing belt off by a mile so no valves are open at the critical instances. Removing the plugs should allow it to turn by hand if that's the problem.
Thank you.
He says he tried that. I've been taking the Rav there for years, and I trust him, but...
He says it needs a new engine.
What else could it be? How does it go from cranking fast to can't turn by hand?

I'll go have a look with my eyes and be sure the plugs are out and that it still doesn't turn.
Any other diagnostic steps I could ask them about before replacing the engine?
Thank you!
 

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I agree that with the plugs out the crank should turn easily in either direction with a breaker bar. If the timing is off and the valves are hitting a piston it will stop in both directions if turned far enough. But any good mechanic would know all that.

Unfortunately I suspect something wrong (broken) down in the connecting rods or crankshaft. If so one of the pistons won't be following the crankshaft. That can be verified using a borescope, or my method, a small light inserted thru each spark plug hole or a thin rod that touches the piston. Any lack of movement by a piston when the crank is moved just a little, except at TDC or BDC, would likely cause enough damage to make engine replacement the best solution.
 
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Discussion Starter #7
Thanks for the ideas. I change my own fluids, alternator, belts... but never got into engine work. I'm trying to figure out if I'm being scammed. He seems like an honest mechanic, but his lot has about 20-30 old cars sitting around. Maybe I just found out why.

He's trying to blame it on me by letting it sit for a couple of weeks. Yes, it's unusual for me to do that, but people do go on vacation. But that still doesn't explain... how does it change from cranking (no engine start) to unable to turn the crank past a certain point. He says he removed the plugs (compression).

Thanks for any ideas. I want to trust him. Been going there for years.
 

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Discussion Starter #8
Here's what I'm guessing, but I'm a novice

The cylinders and pistons ran out of oil because...
It sat for a couple of weeks (with conventional/dino oil)
I ran the starter for 10 seconds trying to start it
I charged the battery
I ran the starter for 5 seconds
It sat for a week
Towed it to the shop
They ran the starter... and the starter broke a rod or something

Or maybe the pistons rusted? Any guesses?? Thanks.
 

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I doubt the problem has anything to do with letting it sit and piston rings and cylinders don't rust that bad for many many years. Failing after parking so short a time is just a coincidence IMO.

As I said a conclusive test for a failed engine is to determine if all four pistons move when the crank is turned as much as it will go. If one doesn't it's replacement engine time.
 
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FWIW I had a 2009 Nissan with variable camshaft timing and if I let the car sit for more than a week I suspect the oil drained out of the camshaft timing oil chamber and caused the valve timing to shift enough and allow the engine to spin easy with low compression and was very hard to start. I would charge the battery fully and then the engine would spin and after a long while enough oil pressure built up and the engine would finally start. I suspect that if I had sprayed some starting ether into the engine it might have caught faster.

Frank 2015 XLE AWD with 20700 miles
 

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Discussion Starter #11
As I said a conclusive test for a failed engine is to determine if all four pistons move when the crank is turned as much as it will go. If one doesn't it's replacement engine time.
Thanks!

I stopped by the shop and asked them to try removing the plugs. They did, and then showed me how the crank only turns a little bit in each direction before it gets stuck.

Is this the same as your recommended test? Or do I need to ask them for that test as well.

The owner says it needs a new motor. The car isn't worth that much with labor, but when I asked if he would consider buying the car, he perked up. His lot is full of these older vehicles, so that makes me wonder if it's a scam they do any time a car is towed in.
 

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Off hand I can't think of a way to fake the crank only moving a little each way w/o something being seriously wrong. So it would appear your choices are either to have another mechanic look at it or just believe him and see what you can get for the car.

Maybe the best approach is to see if you can agree on a purchase price first and then suggest having another mechanic take a look. If he objects he's probably pulling your leg (or your pistons). If not you could have someone else who understands my post 6 test verify the failure in 5 minutes.

Then based on the shop owner's offer you could list it on CL because another mechanic might very well give you more $$$. Just do it promptly because I see storage charges potentially accumulating.

Years ago my niece listed her 4.1 RAV4 with a blown engine on CL. It was gone in about an hour!
 
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Discussion Starter #13
I agree that with the plugs out the crank should turn easily in either direction with a breaker bar. If the timing is off and the valves are hitting a piston it will stop in both directions if turned far enough. But any good mechanic would know all that.

Unfortunately I suspect something wrong (broken) down in the connecting rods or crankshaft. If so one of the pistons won't be following the crankshaft. That can be verified using a borescope, or my method, a small light inserted thru each spark plug hole or a thin rod that touches the piston. Any lack of movement by a piston when the crank is moved just a little, except at TDC or BDC, would likely cause enough damage to make engine replacement the best solution.
Thanks. I got it home and had a chance to try your thin rod in the spark plug hole method. Each piston moves about 2". I am able to easily turn the crank about 1/4 of a complete circle with just a normal wrench, it both directions. Then it stops.

The timing belt is NOT on the sprockets.

Does this mean the engine is working correctly? Maybe it was just some other simple thing keeping it from starting? (The starter motor runs fine.)
 

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The starter is not fine if the engine won't turn over. Likely its pinion gear has been sheared off.

I'm guessing a dropped valve at this point. Damage won't be known until the engine is apart; even if things look good with the head off, one or more piston, rod, and the crank can be toast.
 

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By "dropped a valve" Lugnut means one either broke off or somehow fell into the cylinder. The next step would be to look into each cylinder with a borescope to see if something did fall in and is blocking a piston. In any case do not try to crank it over with the starter until you can turn it completely around with a hand wrench. The belt being off shouldn't stop it.
 
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As a practical matter whatever the issue, a top end problem such as a valve or something in the bottom end - a rod or bearing, Lugnut is correct the engine has to come apart at this point. He or I would do it ourselves but if you have to have to pay to have it done you're likely wasting your money because the chances of it being salvageable are pretty low IMO.

One more thought: You said the starter motor runs fine. As he says that means it's pinion gear must be broken. There is a remote possibility that part of it could have fallen into the bell housing and be blocking movement of the crankshaft. I'd suggest removing the starter and having a look. That's about the only non engine destructive possibility left.
 
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Discussion Starter #17
I have not tried running the starter since before taking it to the shop. I don't know if they did. I imagine they did, as a first step in diagnosis, since it showed up on a tow truck with just a phone call from me "starter cranks fast, engine won't start"

Their claim is that it jumped a tooth, and when they tried to go to TDC, the bottom won't turn 360.

Since the timing belt cover is off, I tried spinning all the sprockets / tensioner with my bare hands. They all spin except the top one, I assume it runs the valves. Is this a useful clue?

Thanks guys.
 

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with my bare hands. They all spin except the top one, I assume it runs the valves. Is this a useful clue?
I don't think I would be able to turn the top sproket with my bare hands. But with a long combination wrench or a socket and breaker bar, yes. The valve springs may give a kick-back, so be careful, and don't force it thus causing more damage.

The thought of a starter-part falling into the bellhousing is interesting, but I don't think the crank would then be able to turn as far as it does. However, I agree -- disconnect the battery, safely secure that cable, then pull the starter. Post a picture of the "business end" of the starter, if possible, for us to see.
 

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Discussion Starter #19
Wow, I'm having difficulty uploading pictures. Even small ones. I'll keep trying...

I think the pinion looks good. (?) Sounds like I should not try to run the starter at this point. Weird that it was cranking before taking it to the shop. Shrug. Moving on.

I have some basic wrenches etc. and a Haynes manual for this generation Rav.
What's next? Rent a bore scope? Remove the valve cover and ?

As a rookie, what's the worst that I could do right? Wreck the engine? :) I'm gathering that the bottom end is just too expensive to repair/rebuild. Would it help to carefully measure how much distance each piston is moving in that 1/4 turn of the crank?

Thanks.
 

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You can buy off Ebay or Amazon a small inspection Endoscope with a 90 degree clip on mirror for the end. They have built in LED and some will connect to a laptop or even a android phone. The image is fair and for less than $15 you can look inside the spark plug holes and also in the oil pan drain hole after removing the oil and look at the crankshaft and connecting rods and make your determination for a course of action. I have used these small cheap endoscope to look inside lawn mower engines.

Frank 2015 Rav4 XLE AWD with 20700 miles
 

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