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Hi, really need help with my '91 33, its a 1.7L SOHC, engine type 30736.
Recently one of the cam belts snapped, rendering the car obviously immobile.
My dilemma is that i cant work out where the timing marks are, or what they should be relative to.
I have found TDC by orientating the "t" on the top of the flywheel in the centre of the viewing hole, however the only mark on the cam pulley on the left side of the vehicle (which didn't break) doesnt appear to align with anything significant at TDC so I have no idea where to set the cam pulley on the right side of the vehicle.
Any help in this matter would be greatly appreciated.
 

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what you need to do is use the hole in the rear cam cover (the metal half) visible from the top. On each pulley there should be a tooth that is marked with an indentation either side. Align this tooth in the centre of the hole while the engine is in TDC, and slip the belt on. This is the correct timing.
Are you sure you don't have bent valves from the belt snap?

Best of luck

Josh.
 

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Discussion Starter #3
I know the hole you mean but only one belt snapped and the one that didnt does not line up with that hole at TDC, thats where my problem lies. i am fairly sure the valves are not bent, i also have a DOHC (worst engine ever designed) 1.7 33 and my father (who is a well respected mechanic) says 1 belt breaking shouldnt effect the valves in a SOHC engine.
Also i aligned the 2 casting marks on the cam pulley at the top while the engine was at TDC, connected the cam belt on the left-hand side of the vehicle and proceeded to crank the engine but it seized (i assume caused by valves hitting the piston/s).
 

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I know the hole you mean but only one belt snapped and the one that didnt does not line up with that hole at TDC, thats where my problem lies. i am fairly sure the valves are not bent, i also have a DOHC (worst engine ever designed) 1.7 33 and my father (who is a well respected mechanic) says 1 belt breaking shouldnt effect the valves in a SOHC engine.
Also i aligned the 2 casting marks on the cam pulley at the top while the engine was at TDC, connected the cam belt on the left-hand side of the vehicle and proceeded to crank the engine but it seized (i assume caused by valves hitting the piston/s).
The 16V Alfa engine the worst ever designed??Shh dont say things like that here!! People will hunt you down!! Its a pure work of art I'd say, one of Alfas best engines. You just need to understand them thats all. Try working on a Japanese car, then you'll see bad design...:rolleyes::p

The holes in the cam covers NEED to align with the tooth on each of the pulleys, if not then the engine will run badly or not at all. However, when the belt is on and tensioned there may be some movement of the pulley and the teeth may not completely align with the hole, but will be close. Make sure you have TDC on the engine by inserting a screwdriver through the plug hole in bore No 1 and watching it.
As for not bending valves in a SOHC engine when only one belt snaps, thats untrue, if you look at the design of the combustion chaber, there isnt much room for error...your valves could be bent or you could be lucky...a compression test will reveal all.

Hope this helps...
 

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Unfortunately most likely the engine is damaged, in 16v engines this is 90% bent valves or even worst... Unlikely with the 8v that are bulletproof in broken belts. I would advise you to have a mechanic check at it first .otherwise you will damage it more....
 

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Valves been bent only has to do with cam timing.

In the boxer engines they run a very tight interference design and really only require to be out of timing by a few teeth on the timing belt to hit pistons.

My brothers 16v was one tooth out on one of the cams and the mechanic mistook it for a lazy lifter, turned out to be a valve hitting the piston...

I'd say if you snapped a cam belt on the SOHC or the DOHC unless the engine stopped instantaneously, valves will most likely be bent.

Also, 77sudti is right with the cam timing marks, you have to remove the cam covers and line everything up when the engine is at TDC.
 
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