running rich on one side? Two part question

[evilways]

I pulled the truck out of the garage tonight and she had to sit outside for several hours, the temperature outside is 28 degrees. When I started her so she could warm up, I went to the rear to watching the steam puff out the side pipes, or should I say pipe. I have true dual exhaust setup with mufflers; they exit out just before the rear tires on each side.

The problem I noticed is that the driver side is pouring out steam constant, but the passenger side is only puffing steam intermittently. Probably 4seconds of steam and 2 seconds no steam. Shouldn’t it be constant on both sides?

Also I am running rich out of my driver side pretty bad and not so much on the passenger side, how is this corrected and does that have to do with the steam in the cold weather that I am seeing.

[Tmiller]

Are you running a dual plane intake?
If so I would guess that your idle circuit on the driverside is out of adjusment or dirty.
The steam is only from the amount of moisture collected in the exhaust as it sets, being that the driverside is rich probably goes with the fact that its running more steam on that side, maybe more carbon buildup in the exhaust for the moisture to build up on.

[cdowns]

what make you think its running rich on one side?are the plugs black?

[68gmsee]

Re: first problem.

Check the color of the steam as it's coming out. If it's white more than likely it's accumulated moisture or condensation. It should stop after the engine warms up. Moisture is also produced by combustion and the heated exhaust will cause condensation "smoke" sort of like those high flying jets in the sky.
Now, if it doesn't stop and if you're losing radiator water, then you probably have a leaking head gasket.

On the other issue, unless you have some sort of separate fuel delivery to the banks as Tmiller said, the gas is pretty much premixed in the intake manifold and it should be delivered equally to all pistons. So, check the spark plugs as Cdowns mentioned for signs of problems.

[Bus Ted Knuckle]

is it cold where you are? It is probably just condensation burning off inside the exhaust.

[Senator350]

any chance of one half of your primaries (one) mixing a bit differently? (I'm not carb guy, just a stab)

carb specs? intake specs? color of plugs after a clean plug run?

[El Jay]

Are you running headers or cast iron manifolds?

Back in the olden days some cars/trucks had a heat riser between the manifold outlet & the beginning of the exhaust pipe.
They had a bimetallic spring to open them when the engine got warm, but they always seemed to crudded up & would stick, usually in the closed position.

[evilways]

This is my set up.
Edelbrock Performer intake
Edelbrock 1405 carb
Fresh 283ci engine
HEI dist.
Long tube headers
Cheap turbo mufflers, no H pipe or crossover.
Brand New AC Delco plugs, gap at .040 for the HEI.
Brand New wires cheapies.

No I have not checked the plugs since install, my reason to believe rich is that on the driver side, it spits moister and smells strong of gas, the passenger side is not as bad, and does not create as much moister.

As far as steam color it is white and does not taste sweet like I would figure for coolant leak, just gas.

[68gmsee]

Originally Posted by evilways

..............As far as steam color it is white and does not taste sweet like I would figure for coolant leak, just gas.

If you're not having to add water to the radiator frequently then it's probably condensation mixed with the unburned gas.

The gas smell could be from a cylinder or cylinders misfiring or an intake valve not seating properly. That's the only way I can think of having unburned gas come out of one bank only.

Your next step is to do a compression test on that bank and maybe even a leak test just to make sure there's no sippage.

[evilways]

Would a radiator pressure test show signs of a leak in the head gasket or intake?

[68gmsee]

Originally Posted by evilways

Would a radiator pressure test show signs of a leak in the head gasket or intake?

It would test your head gaskets. For most of us, a compression test is sufficient, but if a person wanted to pinpoint it to rings, valves or gaskets the cylinder leakdown is a good test.

I copied the following out of a site by this guy and it gives a good detailed descritption of a leak down test.

Excellent info to know:

Doing a leak down test, particularly in conjunction with a compression test, will give you a great deal of additional information and allows problems to be pinpointed. The condition of the engine is determined by measuring the degree to which a cylinder with valves closed leaks air. In simplified terms, if air is pumped into the cylinder at 100 PSI and the gauge reads 97 PSI, then the leak down percentage is 3%. Doing a leak down test is a fairly simple matter. The tester is connected to an air source and is attached to the engine through the spark plug hole. There are two types of instruments, those with single and double gauges. The cost of the tester is usually between $50 and $100 depending on whether it is the single or double gauge and where it is purchased. The double gauge constantly measures the input pressure and the cylinder pressure. The single gauge instrument relies on checking the input pressure and then switching to measure the cylinder pressure. Each requires some adjustment to be accurate. The engine should be rotated so that the valves in the cylinder to be tested are closed and the piston is at top dead center. Tests should be conducted when the engine is warm.

Problems are pinpointed simply by determining where the air is leaking out of the cylinder. Air leaking out of the exhaust system (you can hear it in the exhaust pipe) indicates a problem with the exhaust valve. Air coming out of the carb indicates a bad intake valve or seat. Air going into the crankcase is leaking past the rings and does not indicate a problem if the percentage is low enough. A leak where the air is going into an adjacent cylinder or into the coolant indicates a blown head gasket or cracked head.

A brand new street engine might measure from 5% to 8% depending on the engine, manufacturer, and degree of break in. A B20 engine with unknown history I tested recently measured 10% to 11% per cylinder. Although indicating some wear, the consistency between cylinders and the fact that all of the air was leaking past the rings into the crankcase indicated a reasonable street engine for daily driving that did not need any immediate work. A new race engine should measure under 2%. My current race engine measured 0% after one race and a dyno session. Three years later, it measured between 2% and 3%. After six years, two cylinders are still around 2% while two others are at 5% and 6%. For race engines a leak down test is usually done after each race. The most common problem is valve seats that have been beat up by high RPMs and valve float. Find out which ones are leaking, touch them up and they are good for several more races. For street engines the most common problem is non-hardened exhaust seats that have eroded due to the lack of lead in the fuel.

[Senator350]

any chance that a pin-hole in your exhaust welds would be letting one whole side of your exhaust be collecting moisture?

[evilways]

Very possible, the welds on the collector are hideous (not my work).

[Tmiller]

I ran that edlebrock carb and manifold back in the day and was always cleaning and adjusting the idle air screws.
I'd suggest pulling the idle screws out and spray a bit of carb cleaner in their holes, clean off the adjustment needles and reinstal them. Screw them in until they just touch the seat then back them out 2 turns, this will get them close. Put a vacume guage on to read manifold vacume, start engine, one side at a time screw in then out the adjuster until you get the most vacume possible then do the other side, go back and forth a couple of time to make sure it just right.
I use to do this about 2 times a year just to keep it running right. This should help the uneven fuel mixture from left to right banks with the dual plane manifold.

[Green Machine]

Keep in mind that each side of the carb feeds 2 cylinders on each side, not just the cylinders on its own side.

[Senator350]

so, a driver/passenger difference in fuel mixture would have an equal effect on both sides.

so, the driver or passenger primary isn't the culprit at all.

that was really just a stab... wasn't picturing an intake in my head, but makes sense now.

[Tmiller]

Sorry never relized, been a long time since i ran that intake. Sounds like a weak cylinder more now.
I still suggest cleaning and resetting the idle circuit though. I was doing it often, I knew it was time to do so when it would load up at idle, clean it and would be good for a few months.
Looking at the manifold It may be possible that the fuel may be pooling and running into 3 & 5 where the standing fuel would have to run all the way across the manifold to get to 2 & 8,at idle i don't see enough port velocity to do that, just thinking out loud.
It only take 10 minutes to clean and readjusts these, less indepth as a leak down test.

[evilways]

I am going to pull the plugs and make sure they are all clean and the gap is still good.

As far as the carb, it was just completely cleaned and rebuilt by me and a friend a couple weeks ago, so I don't think that the needles would be dirty yet.
I don't have a spacer as Edelbrock recommends so with the performer carb and the performer intake I figured this would work very well?

I have yet to pressure test the coolant to see if a head gasket is leaking, my only real fear is that this engine was supposedly bored over 30, and if for some reason it is greater than that the possibility of pin hole in the cylinder walls have me nervous.

[68gmsee]

Originally Posted by evilways

...... my only real fear is that this engine was supposedly bored over 30, and if for some reason it is greater than that the possibility of pin hole in the cylinder walls have me nervous.

Not likely at .030 over unless someone screwed it up. Some of these old engines can be bored up to .060 over. You would see a loss of coolant if you had a cracked engine block or pin hole.