Exploring tappet clearances

[burlybryan]

While my radiator is pulled for repair, I'm tackling various maintenance projects - coolant hoses, timing, compression test, t-shooting my cold start probs, v-belt, timing belt/pulley and maybe the crank seal and other oil leaks.

Tonight I got a hold of a 38mm socket and checked all the tappet clearances. On the intake side 2 were .016 and 2 were .017. Well within spec. On exhaust, 3 were .019 and one was .020. Also right in the middle. (spec - intake .015 - .019, exhaust .018 - .021) Now, this is my first Fiat so I have no reference for how the engine should sound, but this engine sounds like a massive sewing machine. Taps at idle and is really loud on acceleration. How normal is this? Should I re-shim to get clearances down the the bottom of the spec? The exhaust manifold leaks (the car has an aftermarket header and I can feel puffs of air esp at the separated middle section) so I think that can have some affect, but I could use some advice on what a baseline tolerance for cam noise should be.

Thanks. (car year, type in sig)

[124JOE]

my after market headder was keaking was well
so i pulled the gasket and seen were it was burnning thru
then i filed the gasket to move it for a better fit
i used the same gasket and reinstalled it holding it in position
it sealed up right and tight

[vandor]

>Tonight I got a hold of a 38mm socket and checked all the tappet clearances.

FWIW, you can turn the engine by putting it in 4th gear and rocking the car.

> Taps at idle and is really loud on acceleration. How normal is this?

Tapping at idle is normal with the hood open, but you should not hear the tappets on acceleration. My guess is that it might be the exhaust leak you are hearing. Correct that and re-listen

>Should I re-shim to get clearances down the the bottom of the spec?

It's fine the way it is.

[burlybryan]

Thanks guys. I'll change the gasket and report back.

I did put the car in gear and jack/turn the rear wheel - it didn't turn the drive shaft. With the radiator out and a borrowed 1 1/2" socket, it was a piece of cake.

[vandor]

I did put the car in gear and jack/turn the rear wheel - it didn't turn the drive shaft.

Yes, I don't think you could do that, you need the weight of the car
But with the rad out I'm sure it was easier using the socket. BTW, a 1.5" socket is the same as 38mm.