3.0 Timing Gears

[HanginInUtah]

Here's a question for all of you that have done a timing belt on the 3.0: Both of the 3.0's I've worked on have had the left side (driver's) cam gear on backwards (in my opinion.) It kind of makes sense to me, in that there is a lip on the gear, and that would help the belt stay on track, I guess? The first engine I did one on, I put both gears on the same way, with the lip on the back side. I figured whoever had done it last, was wrong, because I couldn't see anything in the Toyota service manual that showed it going on that way. But now that I've got a second engine, it seems more than just a coincidence.

Before I install my new belt and goodies, I figured I'd ask. Did I miss something in the manual, or is it a good idea that some tech came up with, or is it the second time some knucklehead installed it incorrectly?

 

[_Frank]

Here's a question for all of you that have done a timing belt on the 3.0: Both of the 3.0's I've worked on have had the left side (driver's) cam gear on backwards (in my opinion.) It kind of makes sense to me, in that there is a lip on the gear, and that would help the belt stay on track, I guess? The first engine I did one on, I put both gears on the same way, with the lip on the back side. I figured whoever had done it last, was wrong, because I couldn't see anything in the Toyota service manual that showed it going on that way. But now that I've got a second engine, it seems more than just a coincidence.

Before I install my new belt and goodies, I figured I'd ask. Did I miss something in the manual, or is it a good idea that some tech came up with, or is it the second time some knucklehead installed it incorrectly?

Based on a quick search on the interwebs, it seems that the drivers side has the lip on the outside. I haven't done a timing belt change so hopefully with more experience can back this up, or not.

 

[nevada]

Here's a question for all of you that have done a timing belt on the 3.0: Both of the 3.0's I've worked on have had the left side (driver's) cam gear on backwards (in my opinion.) It kind of makes sense to me, in that there is a lip on the gear, and that would help the belt stay on track, I guess? The first engine I did one on, I put both gears on the same way, with the lip on the back side. I figured whoever had done it last, was wrong, because I couldn't see anything in the Toyota service manual that showed it going on that way. But now that I've got a second engine, it seems more than just a coincidence.

Before I install my new belt and goodies, I figured I'd ask. Did I miss something in the manual, or is it a good idea that some tech came up with, or is it the second time some knucklehead installed it incorrectly?

yes, one cam gear is supposed to be backwards. though, im not sure of the technical reason.
maybe its to help keep the belt inline properly?

 

[jbo667]

It is to prevent belt tracking and shredding like this:

 

[HanginInUtah]

Wow!! That does make sense! I did put it back together with one of the gears reversed. Glad now that I did!