Dual Cambelt

[bs]

Okay so at work today I had to put a new belt on the drop saw (other one burnt out and broke ), and it got me thinking... Why don't car's have two smaller sized cambelt's? Like a fail safe. So if one breaks the other is there to keep going untill the other goes "pop" to. Or is this just to clever? It will have its flaw's like the broken belt getting caught in everthing, and the owner not knowing that one has broken and then the other goes. I'm sure there would be ways around this tho.

[rollaholic]

cam chain

[Timmo]

Yeah I would imagine

a) When the first cam belt broke it would likely take out the second given that both have around the same designed life.

b) Tensioners etc need to be replaced at the same time...and you cant really have two tensioners (i.e. if one failed then the cambelt would find it hard to turn so you'd have to remove the cambelt/s to replace the tensioners anyway

c) camchains can be used where it is imperitive that the timing gear be fail safe or in situations where access is difficult

d) interference vs non-interference heads.

[sergei]

Okay so at work today I had to put a new belt on the drop saw (other one burnt out and broke ), and it got me thinking... Why don't car's have two smaller sized cambelt's? Like a fail safe. So if one breaks the other is there to keep going untill the other goes "pop" to. Or is this just to clever? It will have its flaw's like the broken belt getting caught in everthing, and the owner not knowing that one has broken and then the other goes. I'm sure there would be ways around this tho.

most likely both will fail at same time

[Lloyd]

If you maintain your vehicle as the manufacturer recommends then there should be no need for a backup. And where does it stop, cast 2 cooling systems and run separate water pumps in case you get a radiator leak?

[bs]

Okay so at work today I had to put a new belt on the drop saw (other one burnt out and broke ), and it got me thinking... Why don't car's have two smaller sized cambelt's? Like a fail safe. So if one breaks the other is there to keep going untill the other goes "pop" to. Or is this just to clever? It will have its flaw's like the broken belt getting caught in everthing, and the owner not knowing that one has broken and then the other goes. I'm sure there would be ways around this tho.

most likely both will fail at same time

Yeah I tought that would most likely happen. Have another saw at work and from the motor to the blade there is three belts on the pullys connecting the two!

[Lloyd]

For grip reasons rather than reliability one would imagine?

[rolla_fxgt]

If you maintain your vehicle as the manufacturer recommends then there should be no need for a backup. And where does it stop, cast 2 cooling systems and run separate water pumps in case you get a radiator leak?

How about just having 2 complete engines, in case one fails, one in the front, one in the back, of course you could just run them both at the same time too if you really wanted I guess that would be about where you stopped, 3 engines would be a bit of overkill

[bs]

For grip reasons rather than reliability one would imagine?

Yeah but they are toothed belts, not grooved.

[RomanV]

You could just cut your cambelt in half down the middle, see how it goes.

[bs]

You could just cut your cambelt in half down the middle, see how it goes.

To bad I'm between car's so can't do it

[cogent]

You could just cut your cambelt in half down the middle, see how it goes.

Thats actually a really awesome trick for changing cambelt without upsetting timing

You cut the old one in half lengthways, then slip the front half off, slip the new belt half on, and cut the second half of the old belt off and finally slip the new belt on all the way

[rollaholic]

ever actually tried it? haha

[Adamal]

c) camchains can be used where it is imperitive that the timing gear be fail safe or in situations where access is difficult

God damn FRIGGEN TOYOTA! Maybe if they designed the 3S for the MR2 rather than designing the 3S and THEN deciding to chuck it in the MR2.... *Grumble grumble. Silvia owners have it easy...*

[Lloyd]

Pfff, MR2 belts are no harder than anything else 3S engined

[cogent]

ever actually tried it? haha

Nope, but I seen it done on a 4AGZE by a dude on another forum.

See, its not quite 'friend of a friend' but its close!

[GTCRSHR]

you saw it on the internets ?

[sleeektoy]

2T-G and 18R-G FTW with cam chains

pity about the FAIL on the tensioner/slipper wear

[Timmo]

c) camchains can be used where it is imperitive that the timing gear be fail safe or in situations where access is difficult

God damn FRIGGEN TOYOTA! Maybe if they designed the 3S for the MR2 rather than designing the 3S and THEN deciding to chuck it in the MR2.... *Grumble grumble. Silvia owners have it easy...*

hehe I know your pain!

[rollaholic]

plenty of transverse cars are a bit of a pain when its cambelt time. not as bad as passats and the like though

cogent - thats rofls, i might have to try it one of these days. seems to me though for the fiddle of cutting the old belt etc etc, it would be easier to just take it off... its not as if 4A's are difficult to set up. maybe if it were a quad cam sub i could understand it a little more!