20V cam gear differences?

[Sam_Q]

I heard that its possible to use all of the mechanical tensioners of a silvertop if they are swapped is that also right? anyone got a pic of one of these tensioners?

[clubagreenie]

I'll edit my last post. They are belt driven aren't they?

If the gears are different sizes, they will interchange as they are not meshing gears they are belt driven. But why would you want to? You will need to change the drive gear (crank gear) or the ratios will be out (interesting results) and need to fit all the right tensioning gear.

I think it's opening up a whole can of mech worms that yo don't want.

Te

[Sam_Q]

yeah thats what i was talking about, I said i woudl have to do that or else the engine wouldnt run.

On Saturday I found out something interesting though, unlike what people have said the exhaust cam gear is identical between the two models and the gears are the same diameter. This also means that the bottom gear is the same. The belt must be longer only to acomodate the hyraulic tensioner. This means that if the tensioner is converted to the silvertop then a silvertop belt can be used. The VVT pulley may be the same diameter but it has a different part number, it may well actuate differently as revhead sujested.

[Mr Revhead]

yeah i checked the belt profile at work yesterday
definitly not different.
forgot to check the pulley sizes though, was pretty sure they wernt different.
just about all the 4age types have different pulley p/n

[JP]

if you want to change to the spring type tensioner instead of the AE111's hydraulic ram, you need to use the AE101 oil pump housing

[Sam_Q]

why is that JP? any chance of a pic?

[JP]

it's because the AE111 housing doesn't have the bosses to mount the spring and bolt style tensioner from memory, I should have some AE111 photo's I can post tomorrow, I've done the hydraulic ram and tensioner on the AE111 a heap of times now, they dont seem to be the most reliable part (eg brand new one failed after 3000km)

[Mr Revhead]

yeah the hydrolic tensioner is the weak link
i make sure that i always insist on a new one when ever selling a cambelt for one.
it WILL fail

[Sam_Q]

ok that would be good thanks, if you are able to and can could you also take a pic of the top of a ae111 piston?

It sounds like it's a prety good move to keep my old spring tensioner.

[-GT-]

I've been having a bit of a dig around and noticed aftermarket suppliers generally have two different part numbers listed for the silvertop timing belt, referenced to early and late model engines. Searching has brought up nothing regarding the differences, or even mention of it, have any of you guys come across this and know what the difference(s) is/are?

If your silvertop is some frankenstein of parts from several engines... I'm not really considering going AM on a timing belt, but haven't spoken to Toyota yet either, i'm assuming from this they're going to ask too.

Has anybody come across any fitment issues with silvertop timing belts?

[Sam_Q]

no, I have ordered 3 lada samara belts now and they fit great (cheap too!)

[3sgte]

yeah the hydrolic tensioner is the weak link
i make sure that i always insist on a new one when ever selling a cambelt for one.
it WILL fail

In what manner do they fail?

[Sam_Q]

you know if I had a silvertop I think I would nor bother with the tensioner and instead fit a silvertop/16v oil pump and tensioner off that

[Mr Revhead]

silvertop doesnt have a hydrolic tensioner so no need to stuff around with that.
aftermarket parts suppliers do not differentiate between the black top and silvertop cambelts, which is why they list two. yet anther reason to use genuine parts.....

silvertop has ONE belt
black top has another
the black top tensioner fails by losing tension, causing the belt to flap around, rubs on the covers etc and falls apart resulting in bendy valves

[3sgte]

Interesting.

In my years as a tech, I have changed literally hundreds of timing belts.
Not one of those saw a problem with the hydraulic tensioner.

Generally, Toyota hydraulic tensioners do not cause issues. I don't think that there was a single split belt at my dealer in 10 years as a result of a bad tensioner. On the other hand, a failed belt as a result of a bad idler bearing or water pump(where applicable) was reasonably common.
The main note I need to make here is that I have only ever done one blacktop, and we don't have 20Vs in Canada, so I can't speak for reliability of the tensioner in that case.