Rotor not turning.....

[flyinpiper]

Okay, just found a better pic. The manual I bought the pics are blurred. So the belt does go around the larger pulley to the crank. Just could not see it behind the crank pulley. I will finish pulling that stuff off in the morning. The only problem I see left is that the left valve cam pointer is missing. Right one is there. Gonna have to take an edumacated guess whare it points to.
Thanks again for your patience fellas...

[BEEK]

camshaft timing marks are cast into the housings, look from the back side

[vandor]

may want to confirm with others, but i think a 77 is a non-interference motor, meaning if the timing is off from broken belt, the valves wont hit the top of the pistons.

Wrong-o, it is an interference engine, both the valves and the auxiliary shaft.

[fiat50state]

happened to me way back in 1984, with my 1979 spyder 2000.........its 90% the one belt you cant see....timing ! not really a major job if your mechanically inclined.... however there are camshaft timing marks to align ( hope you have a haynes repair manual ) along with the crankshaft ...and the real problem is getting the crankshaft pully off . The one huge metric bolt is put on with about 200lbs of torque and its gonna take a air impact wrench to make things easier. After its off you can remove the metal sheild that protects the sprockets and the water pump. I was lucky to find out that when my belt broke while exiting the freeway, that the engine isnt a interferrance type, meening the pistons didnt smash into the valves and cause more damage...........hope this helps.......the other 10% probable cause would be the distributor gear/shaft breaking .....

[ScotcH]

Ok ... sorry to hijack, but are the fiat engines interference or not? I see 2 posts, right after another that contradict each other. It should SEEMS like it would be an interference engine based on the proximity of the pistons to the valves, and the fact that you need valve reliefs in the pistons.

[azruss]

I'm not sure which year was the break, but the early models have valve to piston interference. The later models have recesses in the pistons to eliminate this interference. More important is all the models have interference between the crank and the aux shaft cam. If you are using an electric fuel pump, the aux shaft cam lobe can be ground down to remove the interference.

[DocGraphics]

What I understand is the 2000 motors (79 & up) are non interference (pistons) & the last of the 1800's like mine are too, engine # 132.A1.040.6, the only thing I have found out about the ".6" (vs .05) revision of the 1800 are suppose to have bigger fly cuts on the pistons (like the 2000's) for valve clearance (yet lower compression)

Not an expert on the engine #'s though, please correct me if I'm wrong

[chrisfiat]

remove the timing belt you will find it stripped of teeth in the crank shaft area, then you will be removing the head, this is an interference engine, do not turn this engine over with the starter motor, only move cams aux shaft, crank by hand ( with a wrench) and slowly, any interference, requires you to back up and turn the interfering sprocket out of the way.

[FiatMac]

the only thing I have found out about the ".6" (vs .05) revision of the 1800 are suppose to have bigger fly cuts on the pistons (like the 2000's) for valve clearance (yet lower compression)

The change to Non-interference pistons in the 1800 engine did not result in a lower compression ratio. With the change to larger valve relief pockets the piston compression height was increased to compensate. Below is a summary of compression ratio calculations that demonstrate this.

[DocGraphics]

Good info Stan, I stand corrected

[flyinpiper]

Thanks again for all the help. One last question, I have the new belt in ( you all were right, lost the teeth where I could not see it), timing marks all set correctly, used #4 tdc. Started right up and am ready to use a timing light, but this crappy manual I have says to connect to the number 1 plug wire. Should it not be the number 4 plug wire I connect to since timing points to number 4 tdc?

Next big project : wiring! It's an ugly spider web looking mess.....

[bobplyler]

Thanks again for all the help. One last question, I have the new belt in ( you all were right, lost the teeth where I could not see it), timing marks all set correctly, used #4 tdc. Started right up and am ready to use a timing light, but this crappy manual I have says to connect to the number 1 plug wire. Should it not be the number 4 plug wire I connect to since timing points to number 4 tdc?

You can use either one.(1 or 4)

[aj81spider]

1 and 4 are at TDC at the same time. They just fire on alternate revolutions of the crank. Your light will be flashing every other revolution with either - but at the same time in the revolution so the mark will be seen the same way.

[vandor]

Time it to 10 degrees BTDC instead of the stock setting of zero. It will run a lot better.