I Dodged a Bullet!!

I'm thinking that if the starter, crank and pistons were turning as the cams (and valves) were idle that there may have been some contact with the pistons and valves. I'm just wondering if there was enough vacuum in the cylinders to move the valves out of harm's way (without the timing belt in place). I honestly don't know. If you already have a timing belt purchased, you should be able to install it and see if you have good compression (nothing bent) .

Hopefully I'm overthinking this, and I might be.

 

I appreciate you sharing your knowledge. I'm no mechanic and pretty ignorant when it comes to engines. I have been wrenching on my own motorcycles and cars for a few years but never anything engine related.

I have a cheap borescope camera someone suggested perhaps using it through spark plug holes to inspect pistons. So I may do that at some point along the way...

Just got done cleaning the old water pump gasket residue off the engine. I have new water pump, tensioner and belt (Aisin kit). Just trying to gather some knowledge as I try to put it all back together. I appreciate your insight!

 

IIRC, I used the Aisin kit too. I didn't dare do the work myself so I had a shop I've used in the past do the work for me.

 

Yesterday after much research I came across a decent procedure I was comfortable with.

This was to remove the spark plugs reduce resistance from compression and allow me to turn crank by hand. I turned the crank a full revolution by hand and did not feel it catch on anything stopping at the timing mark (not TDC). Hopping this means the valves were all closed maybe due to vacuum as you mentioned.

I stuck a cheap Amazon borescope camera in the spark plug holes and did not notice any damage on top of the pistons. However one piston seemed to be in a pool of oil, is this normal?

After that I turned the cam pulleys using a 17mm wrench box end (none ratcheting) so I could control each rotation better when fighting the spring tension. I was able to get these set to the timing marks.

Will be slowly trying to get everything back together next few days and just hoping for the best.

Any input from anyone with more experienced than myself based on what I have going on so far would be appreciated.

 

Long story short:
I had a Toyota 22re lose its chain at highway speeds under load. Interference engine came out unscathed. The cam must have stopped with all of the valves closed enough.

The story:
Years ago, I had a '94 pickup with a 22re. I had bought it with a rebuilt motor because the timing chain had chewed through the timing cover into the coolant passage. (Common for the 22re if not caught early)

A few months in, I was accelerating to highway speeds when 'POP' and I had no power. It was a 5 speed so the crank was still turning at a decent rpm for a second or two from the inertia of the truck before I threw the clutch in.

Diagnoses was that the rebuilder had the cam off by a tooth, so it still ran fine, but the chain was slapping the timing guide. Eventually, the chain caught the guide and ripped the top section off and pulled it into the crank sprocket. This blew out the the chain.

I wish I still had pictures. This was before cell phone cameras were any good.

I put it all back together with dealer parts and it purred like a kitten. I didn't check compression, but I had no reason to believe there was a problem.

 

Gives me hope!

 

Okay making some progress. Sadly I screwed up the torque specs for the timing belt tensioner belt and a snapped a bolt in the through hole side. I also discovered that there was only one bolt in my tensioner bracket instead of 2. Found one slightly shorter than the original that seems to work. The bolt in snapped was the original I do have another. Being 4 threads shorter than the original think would cause an issue?

Aside from that I'm posting some photos of the position of my belt.

I did notice one odd part of the new belt where the metal wires in it are exposed in 1 valley between the teeth. The belt is the Aisin kit Mitsuboshi belt.

• First photo is with an inspection mirror of bottom and top of the broken bolt.
• Second picture is the exposed metal threads of the new belt. Is this normal? Or is this something I should be concerned about?
• Third photo is the routing path of the timing belt. Does this look right?
• Forth is the belt position on the crank pulley. I believe this is the correct marking.
• Fifth photo is position on the passenger side cam pulley. Does this look correct?
• Sixth photo is position on driver side came pulley. Does this look right?

Figured I'd post here before setting up and pulling the tension pin (after I figure out how to remove the broken bolt). Any input is appreciated.

 

Truck is coming along almost have her back together... Throwing this out here for those who may need to reuse their timing belt tensioner. I replaced mine as new came with the kit however old one seemed to work fine.

My vice jaw doesn't open enough however I did have this larger c clamp I once used to break the bead of my motorcycle tire. I put it in the vice but that part is not necessary. Large enough c clamps works like a charm.


P.S. I did get the broken bolt out pretty easily Luckily.

 

She's alive... After replacing the belt the truck fired up first try! It wasnt on for long because I haven't reinstalled the fan yet and no coolant. During the short time the car was on I did not hear any weird noise from the engine. No knocking or anything odd. Obd2 didn't detect any fault codes.

Tomorrow will be coolant and fan and she should be good to go in hoping. Following that I'll replace the spark plugs and oil.

In short broken belt while ideling or crawling along in parking lot (I wasn't driving) and so far seems as though no damage to the interference engine in my 2001 tundra.

 

Indeed not.

"Pool" is a subjective quantity but there should not be an appreciable amount of oil on the combustion side of yon piston.

 

First off, congrats for getting this done, bet it feels good knowing you likely saved at least $1k doing the work yourself, and now are more intimate w/your truck.

Second, I'm serious, buy a lottery ticket. If not for the fact snapping the timing belt didn't brick anything, then buy it for the fact it happened in a parking lot. You're one of two people in recent history who've snapped their TB while idling or near-idle who have their engines intact.

And if you win, just pay off the last little bit on my mortgage for my vote of inspiration