FIAT 850 - Aftermarket valve cover2 - Venting modification.

[lezesig1]

-
Paramount was my PREFERENCE to retain the original air cleaner assembly.
I believe in it. It is well designed. Besides...I want to use the horn to hide some
wiring.


Anyone attempting fitting this cover to the FIAT 850...be forewarned/prepared for
some fun to make it work on a stock air cleaner assembly.


What I found was INTERFERENCE. The INTERFERENCE must be eliminated
to make all the players work together in harmony. <enter>Peace sign.


The angulation of ports as well as the diameter of those ports are incorrect for the 850.
Maybe for a model 600 this valve cover would work perfectly fine "as-is" ?


No doubt there are other solutions. Swapping to an EASIER air cleaner assembly would be one.
What I did to make this thing work on a stock 850:


First off- Retain the supplied I.D. but drop the O.D. one size on the tube connectors.
Second- Remove the existing ports on the air cleaner assembly.
Third- Start rebuilding from there.









Notice the VERY TIGHT quarters to make this thing work.
Also notice the seal created for the the access window.
This allows the filter to once again have a positive seal.

Good luck should you find yourself working with this new cover


lezesig
'72 850Sp

 

[Jeff Stich]

Ok...

What I found was INTERFERENCE. The INTERFERENCE must be eliminated to make all the players work together in harmony.

Can you elaborate on the "interference" part? ie: what was interfering with what & where? Your photos don't show the "before", only the "after". I'm guessing it was the horizontal throttle linkage rod & the air cleaner-to-valve cover hose? :confuse2:

The angulation of ports as well as the diameter of those ports are incorrect for the 850... No doubt there are other solutions.

Rather than modifying the air cleaner, maybe just modify (change) the breather port (screw-in brass tube/fitting) from a straight tube to an angled one? (like 45° upward or whatever?) You can also change the size (diameter) of the brass tube at the same time, if desired. Flipping the linkage rod over, so the rod connects to the pivot plate from below rather than from above, can also gain a smidge more room for the hose to clear the rod (if running the hose over the rod rather than under it as in your photos).

Notice the VERY TIGHT quarters to make this thing work.

Looks tight, but tidy. Nicely done!

Does your choke cable hook up & the choke linkage function correctly without interference from your modified port on the bottom of the air cleaner? :hmm2:

 

[lezesig1]

Good points

Hi Jeff,

Staying cool in CA?

"Rather than modifying the air cleaner, maybe just modify (change) the breather port (screw-in brass tube/fitting) from a straight tube to an angled one? (like 45° upward or whatever?) "

Moment. The port is 90 degrees to the oil fill with limited room. The swing from a normal 45 is too great. Not enough room to screw it in. (However) a male/female conversion fitting would work with a straight connector threaded into THAT for an angle change.

"Flipping the linkage rod over, so the rod connects to the pivot plate from below rather than from above, can also gain a smidge more room for the hose to clear the rod"

True. A tad more room could be obtained by inverting the push-pull rod. (However) that would still not provide adequate clearances.

"Does your choke cable hook up & the choke linkage function correctly without interference from your modified port on the bottom of the air cleaner?"

Yes. The entire relationship is without interference, Also, the throttle-choke communication is identical to stock. It was a challenge.

Like said earlier....there are more solutions than this but this was my approach. I wanted to keep the stock air cleaner assembly, carb, and manifold.

"Looks tight, but tidy. Nicely done!"

Thanks. How about you ? Do you have a pic or two of your latest forays into the 850 that you would care to share ? I think the last I viewed was your marathon, in record time, spider teardown and re-erect.

out for now,
lezesig
'72 850Sp

 

[Jeff Stich]

850's?

Staying cool in CA?

Hardly! Did a 75-mile canyon/hills cruise earlier today with a few other 850 friends that started out in cool, balmy weather turning quickly into 95°-104°+ heat with high "tropical" humidity (ie: sticky). We pretty much had to peel ourselves out of our car seats afterwards... :dead:

The cars ran a bit hot (especially in the steep uphill twisties), but thankfully none of them overheated.

I think the last I viewed was your marathon, in record time, spider teardown and re-erect.

Yeah, that was..."fun". Pulled the Racer suspension & swapped it onto the Spider, then the Spider got shipped off to a friend. I haven't done a whole lot with the Racer itself since then, mainly due to...

Do you have a pic or two of your latest forays into the 850 that you would care to share?

The "latest" 850 for me is a very early Euro-spec Fiat 850 Coupe, a non-running project car which I recently worked out a deal for from a long-time 850 friend. It'll get a full mechanical rebuild first, then I'll worry about the cosmetics as time allows. :grin: