Timing chain question

Ferrari Message Board Archive 10/00-8/02
Locked
wwwboard
Posts: 0
Joined: Sun Oct 26, 2008 2:56 pm

Timing chain question

Post by wwwboard »

Posted by Erik Nielsen

Well, the 365 is almost road worthy again, but I need help.  The owners manual says to adjust the timing chain, loosen the setscrew until it makes noise, then tighten it back until the noise goes away (if it doesn't, replace the chain).  

Question:  Do this with the engine hot or cold?

Thanks,
Erik

wwwboard
Posts: 0
Joined: Sun Oct 26, 2008 2:56 pm

Re: Timing chain question

Post by wwwboard »

Posted by Aaron

Erik,

Adjust the timing chain with the engine HOT.  The aluminum/engine will expand significantly as it warms up, increasing the distance between all those gears.  If the chain is adjusted with a cold engine, it will be way to tight hot and big/expensive problems will be imminent.

My experience – with the engine HOT and idling at 950 RPM, as you back out the tension adjustment screw, the chain will start to “clack” (the chain hits the timing cover and makes a “clacking” sound) on the driver side cam chain housing. As you tighten the screw and force the chain adjustment follower into the chain, the clacking will go away, but if you “blip” the engine up to – say 2500, it will again “clack” and a little further tightening (1/2 to 1 turn on the screw) will be necessary to stop this.  If you tighten a little further you will start to hear a “friction kind of noise” which is too tight.  My manual recommends that you tighten until you hear the “friction kind of noise” and than back out 1/4 turn.

I have set my chain half way between the loose side, when you blip the engine and the clack goes away, and the point when you hear the “friction kind of noise”.  The engine has been flawless for 8000 miles, which includes a couple of runs in excess of 140 mph.
(I have been messing with the idle jets, but that is another story for another time)

I have also noted that on cold (sub 40 F) mornings, with the chain hot engine adjusted ½ turn back from the “friction kind of noise”, I get a little “chain clacking” against the housing which quickly goes away as the engine warms.  I have accepted this as normal and OK.

Good luck

Aaron

Locked