Distributor question

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ScottB
Posts: 35
Joined: Sun Mar 14, 2021 12:33 pm
Your car is a: 1980 Fiat 124 FI

Distributor question

Post by ScottB »

My car is running good but does seam to burn and puff white smoke. A few pops on deceleration. Smells to much of exhaust also. I am going through the fuel injection as per Brad Artigue paper. I currently am checking timing. In doing so i have lined up my timing marks which look good. It is hard to see how on the marks the cam marks are from the back side of the timing cover through the holes as it is hard to get a great look, but they seam lined up.

My distributer looks to be firing on cylinder 1. Cap pointed more to cylinder 1. Rotor striker pointed to the notch on distributer body. Rotor arrow pointed to #4. I take it i need to remove the distributor and reinstall in as per the manual to fire on 4, or is this critical. Would this contribute to the smell of exhaust and burning white?

Thanks in advance for any help.
ScottB
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aj81spider
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Posts: 1526
Joined: Fri Mar 11, 2011 9:04 am
Your car is a: 1974 Fiat 124 Spider
Location: Chelmsford, MA

Re: Distributor question

Post by aj81spider »

I'd check your wires to make sure they are going to the right cylinders. If you're really firing on #1 the car shouldn't run at all as you'll be trying to fire on the exhaust stroke.
A.J.

1974 Fiat 124 Spider
2006 Corvette
1981 Spider 2000 (sold 2013 - never should have sold that car)
ScottB
Posts: 35
Joined: Sun Mar 14, 2021 12:33 pm
Your car is a: 1980 Fiat 124 FI

Re: Distributor question

Post by ScottB »

Thanks and i will check more closely how my wire run. The car does run good i must be missing something.
18Fiatsandcounting
Posts: 3798
Joined: Fri Mar 15, 2019 11:23 pm
Your car is a: 1969 and 1971 124 spiders
Location: San Francisco Bay Area

Re: Distributor question

Post by 18Fiatsandcounting »

ScottB wrote:My distributer looks to be firing on cylinder 1. Cap pointed more to cylinder 1. Rotor striker pointed to the notch on distributer body. Rotor arrow pointed to #4. I take it i need to remove the distributor and reinstall in as per the manual to fire on 4, or is this critical. Would this contribute to the smell of exhaust and burning white?
Scott, since it seems to run well, it doesn't sound like anything is seriously amiss. The smell of exhaust could be something fairly simple like a leaking exhaust or muffler, or it could be running rich. However, if running rich, the exhaust is sometimes black rather than white. A white exhaust could simply be normal if the engine is running on a cold day, or it could indicate a coolant leak into the combustion chambers. Does your coolant level drop over time?

Regarding the distributor, here's how I look at it. If the camshaft pulley timing marks are both lined up with the pointer, then the engine should be set to fire on cylinder #4. May not be logical, but that's how Fiat designed it. So, with the cam timing marks lined up, if you remove the distributor cap (without turning the distributor), the rotor metal tip should be pointed pretty close to the metal contact on the inside of the cap that goes to cylinder #4. If the cap were installed of course, which it isn't since you took it off to look at the rotor, but just eyeball it.

Like A.J. suggested, make sure the plug wires are connected in the right order. The firing order is 1-3-4-2-1-3-4-2-etc., so if you get it lined up to number 4 on the distributor, the next wire in the clockwise direction of the rotor should go to #2, the next to #1, and the next to #3. Then back to #4. The distributor rotor turns clockwise when the engine is running.

Hope that makes sense.
-Bryan
ScottB
Posts: 35
Joined: Sun Mar 14, 2021 12:33 pm
Your car is a: 1980 Fiat 124 FI

Re: Distributor question

Post by ScottB »

Thanks Brian.

It has been a little cool here so thinking that is what the white smoke may be. I am thinking it may be an exhaust leak for the smell of exhaust and checking that. The plugs are not black but a whitish brow. Hoping it not the coolant leak into the combustion chamber. My coolant is not dropping, but i have not put may miles on it. More time on the road and go from there.

Thanks for the distributor feedback with the firing order. I will take another look.

Scott
18Fiatsandcounting
Posts: 3798
Joined: Fri Mar 15, 2019 11:23 pm
Your car is a: 1969 and 1971 124 spiders
Location: San Francisco Bay Area

Re: Distributor question

Post by 18Fiatsandcounting »

Scott, whitish-brown on the plugs sounds normal, and it doesn't sound like you have a coolant leak. You know, I'd just drive it for a while to get a feel for how it runs over time.

If it runs pretty good, the timing is probably close enough. The smell of exhaust could be an exhaust leak, or perhaps there's an open hole into the cabin that should be plugged up.

The popping sound on deceleration is usually caused by the mixture going lean (burns more slowly) and so it's still burning as it works its way through the exhaust pipe. Lean mixtures can be caused by a small vacuum leak in the intake. There are other causes, but I'll leave it at that for now.

-Bryan
ScottB
Posts: 35
Joined: Sun Mar 14, 2021 12:33 pm
Your car is a: 1980 Fiat 124 FI

Re: Distributor question

Post by ScottB »

Thanks again Brian. I read the Brad Artigue paper and have been going through the tune up stuff and am on the air leaks actually now. Thanks again for the feedback.

I have owned the car since new. Drove it for about 15 years then parked it in a garage. Just pulled it out and it sure has held up great. So fun back driving it. Just learning the do it yourself maintenance and so grateful for this site, and access to all the parts spots.
ScottB
Posts: 35
Joined: Sun Mar 14, 2021 12:33 pm
Your car is a: 1980 Fiat 124 FI

Re: Distributor question

Post by ScottB »

18Fiatsandcounting wrote:Scott, whitish-brown on the plugs sounds normal, and it doesn't sound like you have a coolant leak. You know, I'd just drive it for a while to get a feel for how it runs over time.

If it runs pretty good, the timing is probably close enough. The smell of exhaust could be an exhaust leak, or perhaps there's an open hole into the cabin that should be plugged up.

The popping sound on deceleration is usually caused by the mixture going lean (burns more slowly) and so it's still burning as it works its way through the exhaust pipe. Lean mixtures can be caused by a small vacuum leak in the intake. There are other causes, but I'll leave it at that for now.

-Bryan
Brian as a follow up to the cooling leak into the combustion chamber you mentioned. I have noticed that i get a fair amount of moisture blowing out of the exhaust pipe especially in the morning when i first fire it up. I don't recall this in the past. Could this be a sign of coolant leak into the combustion chamber? It is very humid here in Vancouver and cool in the morning. The exhaust does not necessarily smell sweet which i read indicated antifreeze burning.

The ball joints go in as soon as they arrive and i will get it out on the road again, and watch the overflow tank to see if i goes though fluid.

Just thought i would revisit this with you.
Thanks
Scott.
18Fiatsandcounting
Posts: 3798
Joined: Fri Mar 15, 2019 11:23 pm
Your car is a: 1969 and 1971 124 spiders
Location: San Francisco Bay Area

Re: Distributor question

Post by 18Fiatsandcounting »

Hi Scott,
Channeling my HS chemistry here, the ideal burning of hydrocarbons (gasoline) should produce just water and carbon dioxide. Given the temperature of combustion, the water is steam rather than liquid water, and this steam is more visible on cold mornings and when it's humid outside.

My guess is your engine is just fine. The ball joints, well, that could be a different story... :D

-Bryan
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