Technical 1980 124 2000 interference engine?

[Ster1]

Hi folks,

Quick question for you: is the 1980 2000 fi engine interference or free? In other words, if you break the timing belt, will the valves interfere (engine damage) or will the engine just spin? Looking at the piston crowns, it looks like it might not be an interference engine. I'm hopeful.

 

[F123C]

All the Fiat 124 twin cam engines are interference type.

Also, it's necessary to set the timing mark (small hole) on the auxiliary drive shaft to the correct position when fitting a timing belt/setting the valve timing - on most if not all Fiat twin cam engines, there's an eccentric on this shaft that can collide with one of the crank big ends if incorrectly set. Iirc this timing mark/hole is set at 34 degrees clockwise from the vertical position.

Hth,

Al.

 

[Ster1]

Thanks Al! It turns out my timing belt was actually there, intact. It was narrower than I thought, and didn't see it. Rookie mistake. Anyway, I'm going to spin the engine today and maybe even get a compression check. I have to go get a crankshaft socket to turn it slowly.

 

[F123C]

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------- I have to go get a crankshaft socket to turn it slowly.

The crank pulley nut is usually 38mm which is virtually the same as 1-1/2 inch AF/ American/Standard.

Another alternative (and maybe easier for access) for turning the engine slowly is to put a wrench or socket on the alternator pulley nut, iirc it's either 19mm (= 3/4 inch) or 22mm (=7/8 inch). If the pulley slips inside the drive belt, just push on the slack side of the belt with your fingers while turning the wrench/socket.

Iirc, the crank pulley doesn't have to be removed when changing the timing belt, so you might not need the 38mm socket

If you really want to thank me, just click on the smiley face in the bottom r/h corner of this post (I'm on a mission ).

Al.

 

[Ster1]

I used a 1-1/2 socket, no problem. I pulled the radiator, it was trashed anyway. I put a little oil in each cylinder (the motor had been sitting for around 20 years), and it turns freely! Static cold (wet) compression shows between 140 and 150 all 4 cylinders. I'm impressed so far.