Timjng belt broke on my 99 4 Runner and mechanic claims that I have most likely damaged the valves too. He did say it had the non-interfearance thing in it, so how is it likely that the valves are damaged when everything I have seen in various posts on the internet say the noninterference thing prevents damage from occurring?

 

The 5VZ-FE engine is a non-interference engine so the valves could not be damaged by a broken timing belt since the pistons do not go into the valve travel areas. has the timing belt been replaced?

 

No, not yet. Wasn't sure whether to replace it I was looking at a $3000 bill to repair the valves too.

 

+1



Andreas

 

Time for a new mechanic!!! maybe ??

Either they are clueless with the 3.4 or they are looking for some fast money for doing nothing.

If they are clueless they are just figuring on worst case and the valves are toast.

This is one of those things have you been using these people for years ??

It is impossible to keep up with all the different engines out there.

 

Could be a fugazi mechanic. Lord knows there are a million out there. Please take your truck to someone who knows Toyota's.
There is quite a laundry list of parts you need to replace while you're doing the belt so do your homework before letting billy bob tear into it.
There is a sticky at the top of the page specifically about timing belts

 

Apparently the timing belt didn't break at all. I was informed that the shaft or wheel that turned the timing belt sheared of compleatly, which has caused untold damage, costing thousands of $ to repair.
Thank you for all of your guidance. It is greatly appreciated.

 

Ok this is a little different .

Sounds like the crank pulley came loose .

Depending just what happened if it wiped the key way or wore the threads beyond repairing on the crank .

I could see where the labor to pull and install the engine replace the crank plus other needed repairs could get expensive.

Then with this kind of thing you really don`t know till everything is torn down and inspected.

 

How does a crank pulley come loose? Bolts not torqued from previous repair?

 

Correct....likely not torqued properly. It's happened before.....

 

According to the mechanic it didn't come loose - it was sheared off.
And now for the rest of the story -
Probably should have mention this earlier, but didn't think the particulars mattered if it was just a broken timing belt. My car sat for 9 months because, mid winter I realized we weren't going to see the snow we usually have. I just drove my Kia and didn't know that one is supposed to drive your cars around regularly. Since it sat so long it barely idled. I attempted to DIY it to get it back on the road. I researched and found what was probably really good instructions on doing so using a product called Sea Foam. Most unfortunately, I failed to fully follow all of the instructions and pretty much skipped right to the "give it a couple 0 to 60 mph.". I was on my second 0 to 60 when I heard a couple of loud groans and then she just shut down and died. Pretty damn expensive lesson.

 

I'm still stumped......did the gear that runs the timing belt break away from the keyway or did the actual crank shaft snap?
How does the sea foam work into this?
Definitely a strange chain of events but please report back especially if its a lesson learned scenario.

 

Most times the for one reason or the other the key way or the key itself is worn

Could be it was never torqued to specs

Wrong size key was used because it was close enough

Over time it moves a little till it gets real sloppy and just shears right off allowing things to spin free.

At this time the crank and the pulley are to the point it is cheaper to replace

Once the crank is out what other work needs to be done

At this point you figure out the most cost effective route to go

It was not so much the Sea Foam but the romping on the engine that caused the problem

 

Most likely a cam seized and sheared the pulley off. I have seen this several times. Cause is oil starvation to the cams due to sludge, poor oil quality, and lack of timely oil changes. Just swapped 5vz last week that had this. Poor little guy never had a chance.

 

I'm quite sure it was definatley me and the romping. Had I followed the guys Sea Foam instructions I fully I probably could have avoided this mess. Now I need to decide whether to buy a new engine or a rebuilt engine. The mechanic says I should do neither since I have 199,000+ on old Betsy, but I love my 4Runner and don't particularly want anothercar payment.

 

I gotta say if your paying someone to do all this work you might want to think about another vehicle and sell this one just like it sits

If you take what the sale brings plus what the cost would have been it should be pretty easy to figure out.

It sounds like your mechanic either does not want the job or is really trying to give you good advice.

After all it is your call

 

where are you located? may be worth finding some buddies and getting a motor from a junk yard.

 

[QUOTE=wyoming9;52286588] I gotta say if your paying someone to do all this work you might want to think about another vehicle and sell this one just like it sits

If you take what the sale brings plus what the cost would have been it should be pretty easy to figure out.

It sounds like your mechanic either does not want the job or is really trying to give you good advice.

I don't even know how to value a vehicle with a blow engine. Say I take the $6500 that a remanufactured engine and a $1000 or $2000 from selling my broken 4Runner, I will have $8500 at most, which will buy me someone else's problems, yes?

 

I had a very similar experience the year before last. My timing belt and water pump had been done right before I bought my 4Runner. The mechanic didn't use a new crank pulley bolt when he reinstalled it though. That bolt has to be torqued down to like 180 ft. lbs. or something. The bolt backed out after a couple hundred miles, and the pulley slipped forward on the crank causing the woodruff key and crank end to completely wear down. It was either tear the entire engine apart to replace the crank, or buy a new engine. I ended up buying a JDM engine off of eBay with 40k miles on it. I had a friends shop install the engine for me. Paid $1595 for the engine shipped, and $1300 for the shop to pull the old engine, swap the supercharger onto the new engine, then install the new engine in the 4Runner. Ended up costing me less to go that route and I now know that I have an engine that will last for years to come.

 

By the way, I was at 212,000 miles when this incident occured. I am now at 244,000, and it is still running like a champ!! That's the only thing that irritates me. I really wanted to see what I could get out of the original engine! The supercharger was installed on it at the dealer when it was brand new. Other than seeping valve covers, it had no other issues, and still ran like a scalded dog!! The only things wrong with it is the electric antenna motor is worn out, and the clock on the dash flickers. It is a 2000 T4R Limited 4X4, and I wouldn't hesitate to drive it across the country and back. It didn't, nor does it now have a check engine light. It is a beast!!