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Matt, Mechanical Engineer
Category: Car
Satisfied Customers: 22920
Experience:  BEng hons Mech engineering, in auto industry 22 years
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ferrari 400i 1982 , have n/s head off for gasket job, but can

Customer Question

ferrari 400i 1982 , have n/s head off for gasket job, but can not find mark on front crankshaft pully to set valve timing, any one to advise me, i would be most grateful.
Submitted: 3 years ago.
Category: Car
Expert:  Matt replied 3 years ago.

I suspect on an engine like this there will be no timing marks and its best to set it up with equal lift on overlap with the engine at TDC on no.1 cylinder

1st you'll have to determine TDC
First thing to do is confirm that you're on the compression stroke on No1 (No1 is the first on the RHS with the engine in front of you) by turning it by hand with the spark plug removed and your thumb in the hole. Once you're sure that this is compressing you can use the marks on the front pulley to confirm the TDC position and also confirm this with a small length of wire into the plughole. If you hold it firmly down against the piston as it comes up you should be able to feel when its stops rising and there'll be a dead spot of 8-10° before its starts to fall again.

If you need to be certain, then you need to make up a piston dead stop with a modified spark plug and a length of bolt screwed into the plug body so the piston has something solid to run into. you then attach a degree wheel to the front pulley and make up a pointer.

With the degree wheel held on with blutak you turn the engine over until it hits the piston stop, not the degree reading and turn it back the other way and again note the degree number, you then use the mid way point between the two readings as TDC.

With this all set and you now knowing where TDC is you just have to confirm that the rotor arm is coming up to the correct post / plug inside the dizzy as its easy to get the drive gear a tooth out so your old lead order no longer works.

I do this by setting the engine to TDC and then set a pointer where the rotor arm is aligned and then replace the cap and ensure its just in front of no 1 dizzy lead post.