Loss of idle and lack of power

[4babycar]

My usually faithful, 80 spider has recently decided to throw a little hissy fit since the Free-iat came home. Anyway, my 80 has the same 2L engine but has been converted to duel 13/15 IDFs. I have fuel to the carbs, new plugs, new cap and rotor but the symptoms persist.

The symptoms started with a slight miss and the smell of a rich mixture. I originally thought it was a fouled plug but the symptoms got worse before I could install the new plugs. I was driving normally and slowing to a stop when the car died. It started back up but had less power. Now it takes a lot to get the car started but will idle with the choke just about all the way out. If I back off the choke or the rpm's, it stutters and dies. If I hold the rpms high, I can drive for short distances (around the block).

What I have done: Changed the plugs, new cap and rotor. Check grounds to ensure good and consistent spark. Checked the fuel and I know I have fuel to the front carb and the accelerator pumps on all for cylinders are functioning. I tried a bit of carb cleaner down the throats but not effect. I have also checked the oil (normal level) and the radiator and do not see any signs of mixing.

So, what do you all think? I am thinking I need to perform a compression test to determine if I have a carb problem or a head gasket issue. Opinions? Suggestions? All are appreciated.

[So Cal Mark]

sounds like you either have a restriced jet in a carb or a very large vacuum leak, like a split brake booster hose. When you hold the rpm high, does the engine run smoothly?

[4babycar]

The 13/15 IDF don't have vacuum ports. No vacuum advance or brake booster connections. I was suspecting something with the jets or possibly a head gasket between two cylinders. Hense why I wanted to perform the compression test.

Does anyone have some material that they could send on rebuilding these carbs? (Webber 40 IDF 13/15 - Old style) Is this something I should try on my own or best to shop out? I have little (read: no) carb experience prior to this car and haven't touched the carbs, outside of tuning per Mr. Artiques manuals. I have read the many references to poor rebuilds so I am cautious.

[So Cal Mark]

a vacuum port isn't a large enough leak to cause your trouble, unless it's the brake booster hose. It would have to be a manifold leak or carb base

[4babycar]

Today I took out all the jets and cleaned them. None were clogged. I sprayed AFM (air flow meter cleaner - I was out of carb cleaner) at the base of the carbs and the car bogged down and would slowly rise back up. I guess I have a manifold gasket leak but I would have expected the engine to rev with cleaner not bog. Does this sound right? - Thanks

[So Cal Mark]

what you're really looking for is change; it's hard to tell how much chemical you got into one cylinder to affect it

[4babycar]

Ok, I check my inventory of parts and accessories and found that I have 4 new carb to manifold gaskets. Now my new batch of questions are these:

The gaskets I have are the hard paper/cardboard type - is this the recommended type? I have a roll of Fel-pro cut your own gasket and could replicate the gaskets that I have in the Fel-pro material, if that is necessary or would be of benefit.

Second, the carbs look relatively easy to get off of the manifold, other than some tight spaces but do they need come off together, since they are center linked? I was not the one who installed these carbs so I have no history on putting them together or installation so I have no idea how the center linkage is assembled and it wasn't apparent when I looked this evening. Can someone provide some insight?

Finally, with the gaskets, should I apply any sealent to them prior to installation? If so what type and both sides or only one?

As always thanks for you help!

[4babycar]

Bump

[4babycar]

Well after fighting with the carb bolts between the carb and cam tower and changing the first carb gasket twice, I put everything back together and started her up! Feeling proud of myself, I was enjoying the moment until I heard the miss. Still not right. After several hours of diagnosis - before calling a friend with a compression gauge and a lot more knowledge than me - BLOWN HEAD GASKET! ARGRRRRR! Blown between cylinders 3 and 4. Now I sit, with a cold bottle of installation fluid in my hand and two dead Fiats in the driveway. This SUCKS!

I guess on a positive note, by the end of June (with any luck) I should be quite proficient in changing head gaskets on Fiat 2L engines, both carb'd and FI! - Provided one looks at things in a positive light.....