2005 4.7L timing belt replacement question.

[Herc]

Owner of a 2005 4wd w/4.7L V8. In August I did pre-emptive maintenance on my 4Runner by replacing the timing belt at ~90,000 miles (along with some other minor things). When I got her back they had messed up hooking up the cooling hoses and it was leaking like a sieve. So back it went. Then it threw off a CEL and whirring noise on start-up. Back it went. They didn't even run the CEL codes and said it was a bad battery. Few weeks later the air-pump blew. Took to a different dealer and they said water had gotten into the pump and air-pump valves (note the previous dealer and trouble with cooling hoses?). Now I'm losing compression on one of the cylinders and everything points to a burnt valve.

Question: If the dealer that did the timing belt mucked up the install then could that be the culprit that led to valve damage? After misdiagnosing an air-pump CEL as a bad battery I would refuse to let them work on my lawn-mower now!

 

[Derek G]

It's very possible. The Toyota 4.7 V8 is a non interference engine, which means unlike other types of engines that just stop running when the timing belt breaks, these engines will basically grenade themselves if the timing belt breaks causing the valves and push rods to drop into the engine. I'm am by no means an engine expert, but it sounds like they misaligned the belt or possibly rotated the crank shaft with the belt off or just generally screwed up somewhere along the line. I'm sure someone with a little more experience will chime in here too.

 

[hades]

I didn't need to read this! I dropped my 2005 off this morning for a timing belt replacement. I am nervous it's gonna be a mess.

 

[black4vcobra]

It's very possible. The Toyota 4.7 V8 is a non interference engine, which means unlike other types of engines that just stop running when the timing belt breaks, these engines will basically grenade themselves if the timing belt breaks causing the valves and push rods to drop into the engine. I'm am by no means an engine expert, but it sounds like they misaligned the belt or possibly rotated the crank shaft with the belt off or just generally screwed up somewhere along the line. I'm sure someone with a little more experience will chime in here too.

you got the wording backwards, the 4.7L is an interference engine, meaning that pistons and valves will hit if the timing belt breaks

 

[Herc]

I didn't need to read this! I dropped my 2005 off this morning for a timing belt replacement. I am nervous it's gonna be a mess.

Sorry. Hopefully the tech that does yours is more experienced then the one that did mine. Reading how-to' it seems to be a simple process just very time consuming.

 

[corradovrt]

kinda sounds like the timing might just be slightly off,

has it been pulled back apart to verify timing??

 

[A/V1]

Damn that sucks! Even at a stealership where everybody is supposed to be trained well... or somewhat well. This is one of the reasons it urks me when I hear folks say "take it to the dealership instead of a local shop. You know it'll get done right!" When I had my timing belt done back at 95K miles, I had a smaller garage in Little Rock (Fosters Garage) do mine and did a great job!

Now I'm at 203K and VERY due for another belt change, and wouldn't trust any one here in the DFW area to do it. I'll just have to do my homework and find a place, or I'll bite the bullet and do it myself.

So which stealership did you take your Runner to?

 

[hades]

I took mine to Jim mcnatt in denton.

The miss quoted the job - but they aren't charging mor - but it's taking forever and I am supposed to leave town tonight.

 

[DC runner]

None of the issues discussed by op are from a botched timing belt install.

When the timing belt on an interference engine goes, so does the engine. It doesn't crop up as a coolant leak or code while the engine runs.

In an interference engine, the piston is physically prevented from going its full measure by the timing belt. This means without the belt to stop it, the piston now slams full force into the top of the chamber and hits everything. When a belt goes, it isn't a slow death....it is instant.


No. What op has is a case of sloppy work from.the techs.you have to remove the entire front of the engine to get to the belt. This means the coolant system. Clearly they were less than careful


Here is what you do. You get a full quote from the shop you intend to have fix it. You take that to the dealer that botched the job, remind them of the utterly crap job they did and inform them yet another issue related to their horrid work has cropped up.

You say,very nicel, that you would like them to pay for the repairs or you are walking to small claims and suing them.as well as contacting Toyota hq.

 

[V8Man]

The Big Bang!

None of the issues discussed by op are from a botched timing belt install.

When the timing belt on an interference engine goes, so does the engine. It doesn't crop up as a coolant leak or code while the engine runs.

In an interference engine, the piston is physically prevented from going its full measure by the timing belt. This means without the belt to stop it, the piston now slams full force into the top of the chamber and hits everything. When a belt goes, it isn't a slow death....it is instant.


No. What op has is a case of sloppy work from.the techs.you have to remove the entire front of the engine to get to the belt. This means the coolant system. Clearly they were less than careful


Here is what you do. You get a full quote from the shop you intend to have fix it. You take that to the dealer that botched the job, remind them of the utterly crap job they did and inform them yet another issue related to their horrid work has cropped up.

You say,very nicel, that you would like them to pay for the repairs or you are walking to small claims and suing them.as well as contacting Toyota hq.

While I agree on how to solve the problem with the dealer that did the work, I have to disagree with your description of a mistimed interference engine.
The piston does not hit the top of the chamber. For that to take place the connecting rod would have to increase in length. What happens in a mistimed engine or with a broken timing belt is the piston hits an open valve. With the engine mistimed a valve is opened into the cylinder when the piston is in the same space. Thus the term interference, the valves interfere with the piston. The result is disastrous, bent valves; holes knocked into the top of pistons, and sometimes bent rods. The timing belt times the cam shafts and subsequently the valves, not the crank, rods, and pistons.

 

[Herc]

Toyota of Lewisville is handling the vehicle now. They are under new management and seem eager to please. Slooow as molasses but seem thorough enough.

Despite the glaringly obvious of what the root cause is. I don't have definitive proof. I will be contacting original dealership and then Toyota regardless. Can't hurt at this point.

 

[DC runner]

While I agree on how to solve the problem with the dealer that did the work, I have to disagree with your description of a mistimed interference engine.
The piston does not hit the top of the chamber. For that to take place the connecting rod would have to increase in length. What happens in a mistimed engine or with a broken timing belt is the piston hits an open valve. With the engine mistimed a valve is opened into the cylinder when the piston is in the same space. Thus the term interference, the valves interfere with the piston. The result is disastrous, bent valves; holes knocked into the top of pistons, and sometimes bent rods. The timing belt times the cam shafts and subsequently the valves, not the crank, rods, and pistons.

I typed this on a phone and mis-spoke, but yea. It smacks a valve.

 

[V8Man]

Happens

I typed this on a phone and mis-spoke, but yea. It smacks a valve.

:thumb3:
Yes I know what you mean. I usually look at the forum in bed on my phone as well. right before passing out, with visions of T4R in my head. Some of my posts get a little goofy.

 

[MikeInNH]

I hear folks say "take it to the dealership instead of a local shop. You know it'll get done right!"

I've heard that line ever since I bought my first car back in the mid 70's. Didn't hold true then and doesn't hold true now. I've found that GOOD independents are usually far superior to any dealership mechanic. They usually have more experience and a vast knowledge that gives them a good edge over dealership mechanics.

 

[awdjunkies]

I've heard that line ever since I bought my first car back in the mid 70's. Didn't hold true then and doesn't hold true now. I've found that GOOD independents are usually far superior to any dealership mechanic. They usually have more experience and a vast knowledge that gives them a good edge over dealership mechanics.

Not only this^ , they(Indy's) have the patience to think outside the box, as well as use other means/resources to pull a job in order to finish it right. Whereas the dealership mechanics are strictly by the book and have little to zero knowledge on using different means to get the job done, not to mention aftermarket support.

 

[xxaarraa]

I don't know about your state, but in MA, most repair jobs are covered by a 12 month/12k miles (?) warranty. I would nail the original dealership and make them pay. A simple call to the service manager saying "I am considering legal options" usually does the trick, if they have half a brain.

 

[V8Man]

The one thing the dealers have over the independent guys is the new car warrantees. The independent guys will not see a "new" model car until the manufacture's warranty is up. Three years, 36K up to 100K miles on some cars. Then car companies make "special tools" and equipment requirements in order to get the job done. It's true there is a lot of good guys out there you just have to find them.

 

[WillK]

Sorry, but what's an air pump?? I'm not familiar with that term?

 

[corradovrt]

damn you guys must have some terrible dealers around you.

im a tech at lexus and we are constantly getting vehicles towed in from independent shops, and also alot of new clients from other dealers that couldnt get the problem/repair sorted out. our management can be a joke at times, but as far as repairs we pride ourselves in doing top notch work

 

[satanos6668280]

im a tech at a small independant that specializes in toyota, lexus, subaru and honda. the owner worked at a toyota dealer for 30+ yrs and got tired of ripping ppl off so he went out on his own in 2000 and ive been here for 10 yrs. but like someone said alot of the new stuff we wont see until the warranty is out or until a major problem arrises after 100000 miles. To the op i have no idea what they are talking about with coolant getting in the air pump. unless they are saying the a/c compressor is bad which is quite possible. the 2uz engine has no air pump. i agree to take the covers off and look for the timing marks they are easy to mix up as there is a line and a T mark every one sets it to the T and that is wrong. the cam gears get aligned to the line mark that is straight up. pull the 2 upper covers just a bunch of 10mm bolts and 2 10mm nuts