Timing belt and damage

[cencyc]

I just got a 2002 4Runner w/125k on it. I've started working on fixing known an avoidable problems, including getting estimates on timing belt replacement (does not appear to have been done). I've gone to a Toyota specialist and a 4WD specialist and they both claim that there will likely be damage if the timing belt breaks while the engine is running at normal speed. The first place said that if the rpms were high enough, damage could be done. As far as I know, non-interference means non-interference. Pistons, piston rods, cam lobes, valves don't stretch and shrink according to rpms (well...not at the macro level). The second shop first said that it was an interference engine, when I disagreed, they said that they had to research it. When they called me back, the new person said that no it was not an interference engine, but that the timing belt breaking could cause "other damage". And he got very "umm well" when I pressed on details. To say the least, neither place left me with a warm and fuzzy feeling.

Has anyone experienced engine or "other" damage with 3.4l V6 when the timing belt broke while driving?

 

[rjaudi]

The engine should be fine if it breaks, but just think about the fact you have a belt whipping around the engine I'm sure things might get hit. It is not the belt that I would be worried about. I would do the timing job to replace the water pump. They usually go out before the belt from what I have heard. I recommend replacing the idler bearings while you are in there.

 

[01t4rnr]

mine has 116K on it and after reading your post decided to call my Toyota dealer about 50 miles away. He said for $620 they replace the timing belt, water pump, serpentine belts, seals etc . Seems like a pretty good deal compared to the other prices ive been reading in the forums. I asked about any possible damage and he said something about the valves but said not very likely anything major would happen if it were to break. Good peace of mind and when taxes come in ill prob. go ahead and get that taken care of.

 

[Jamacee]

I am in the same boat. Except I blew my wad to get the truck in the 1st place. I am waiting for funds for the parts. Personally I have never changed one myself but I want to. I think it would be good to know how to do anyways.

Does anyone have a link to a good pic heavy write up about 5vz TB changing?

 

[athlon450]

Here is a good resource for all you DIY's about TB and much more!
http://www.toyota-4runner.org/3rd-gen-t4rs/69744-tutorial-documentation-reference.html

 

[Elton H]

i got a really nice kit off ebay oem parts without the name and cost for around 300 bucks i followed the 4x4 wire writeup... did the work my self its really not a hard job just takes a good days work and the right tools

 

[durrell]

I just don't want to do it myself. My normal mechanic quoted me 245 dollars labor if I provide all parts. I'm gonna buy the 288 dollar kit.

I have 175k and assume the belt is original. I see no sticker to indicate otherwise. It really sucks, too, because I'm going to have to put my 285's off for a long time so I can get the t-belt installed with my tax return.

 

[jsmarine]

i got a really nice kit off ebay oem parts without the name and cost for around 300 bucks i followed the 4x4 wire writeup... did the work my self its really not a hard job just takes a good days work and the right tools

I got that exact same kit, just installed it this past weekend. It was a very nice kit, good quality parts.

 

[YotaZach85]

i got a really nice kit off ebay oem parts without the name and cost for around 300 bucks i followed the 4x4 wire writeup... did the work my self its really not a hard job just takes a good days work and the right tools

I agree with everything you said here! I got the same kit and this was my first T-belt job and it only took anout 5 hours from start to finish with using only basic hand tools. The hardest part for me was compressing the tensioner, (b/c I didnt replace it) I dont have a vise at home so I ended up using the stock bottle jack and front tow hook to compress it to get the allen wrench through it, may not be Toyota approved way of doing it but it worked

 

[Blitzkrieg]

1) The 3.4 is a non-interference motor. The valves will NOT hit the pistons if the timing belt breaks. If you talk to somebody who tells you that is wrong OR they don't know, find another mechanic.
2) The damage you could experience if the belt breaks would be when it wads up around the crankshaft pulley or timing pulleys. Most likely to things like the covers.

That being said, the answers to everything you probably want to know are here:

http://www.toyota-4runner.org/3rd-gen-t4rs/71802-timing-belt-advice-needed-badly.html

 

[Elton H]

ya my problem was at 188k the water pump said im done and seized and started to melt the belt good thing i was only about 2 miles from home

 

[4wdGunner]

Last owner said the belt was done about 60-80k miles ago. No proof or documents though. I need to tackle this job myself too...done a couple timing belt jobs b4. Not my favorite but kind of curious on how this motor works.

 

[rjaudi]

I will again recommend that anyone getting the timing belt done with over 100k miles replace the tensioner and idlers. The 300 dollar kit on ebay cover this. There is also a Toyota dealer on ebay that I bought my parts for 400 in 2 kits with all OEM parts. My idler bearing that connects to the tensioner was going out so I had to redo the timing belt job at 50k miles into the last belt job. This is a good DIY if you are somewhat mechanically inclined.

 

[fenrisx]

I'll second what everyone else has said. The kit on eBay that is $288 from AirCabinMan (Item #190488321298 for 2 more days) is ALL OEM. There is another kit for $240 that is mostly OEM, but there are one or two parts that are not.

Also, just for reference sake... I e-mailed the local Toyota dealership to see how much they would charge in labor+parts to swap EVERYTHING in the kit above, and they said parts would be $470, and labor would be $895 + tax and shop supplies. So if you're mechanic is going to charge you less than $300 & you trust his work then that's definitely a good price.

I'll be having mine done next week, hopefully, by a local guy who runs a shop specializing in Land Cruisers. I honestly don't have the time to try and do it myself, but I'd like to. Maybe next time.

 

[BTO]

The hardest part for me was compressing the tensioner, (b/c I didnt replace it) I dont have a vise at home so I ended up using the stock bottle jack and front tow hook to compress it to get the allen wrench through it, may not be Toyota approved way of doing it but it worked

I'm not fully understanding this method. Can you go into more detail? How was the tow hook used?

 

[Whackmaster]

I just got a 2002 4Runner w/125k on it. I've started working on fixing known an avoidable problems, including getting estimates on timing belt replacement (does not appear to have been done). I've gone to a Toyota specialist and a 4WD specialist and they both claim that there will likely be damage if the timing belt breaks while the engine is running at normal speed. The first place said that if the rpms were high enough, damage could be done. As far as I know, non-interference means non-interference. Pistons, piston rods, cam lobes, valves don't stretch and shrink according to rpms (well...not at the macro level). The second shop first said that it was an interference engine, when I disagreed, they said that they had to research it. When they called me back, the new person said that no it was not an interference engine, but that the timing belt breaking could cause "other damage". And he got very "umm well" when I pressed on details. To say the least, neither place left me with a warm and fuzzy feeling.

Has anyone experienced engine or "other" damage with 3.4l V6 when the timing belt broke while driving?

Find a different mechanic or do it yourself, it isn't that hard....Those mechanics sound like they don't know what they are talking about..........

 

[cencyc]

Find a different mechanic or do it yourself, it isn't that hard....Those mechanics sound like they don't know what they are talking about..........

That is my feeling exactly. I also wanted to make sure I was not being wrong myself (been years since I turned wrenches and it was not on a 4Runner).

 

[ironhippy]

Is it possible you weren't talking to the actual mechanics? I know if I call the local 4wd place in my town, a sales guy will answer. While he may know a bit about engines but he is not the guy who would be doing the work. That guy is in the back turning wrenches.

that's all I got.