help with my all original P23 motor with 77,000 miles

[rolliejoe]

I was having a plug fouling problem with white smoke and unburned fuel smell from the exhaust. I removed the spring from under the step up piston to try to eliminate a source of potential flooding, it helped but still the white smoke. Tuned up the ignition (new points, condenser, cap, rotor) and the it's running better but still white smoke. The smoke does go away when running the engine at ~2500 rpm (no tach), but when revving from an ~2500 idle it smokes. Plugs look better but all of them were wet. Here's some compression readings:

COLD / HOT

1- 80psi / 90

2- 85 / 95

3- 90 / 100

4- 80 / 90

5- 80 / 90

6- 70 / 70

thanks in advance

[rolliejoe]

picture of #1 plug:

[Don Coatney]

What air cleaner are you using?

[Plymouthy Adams]

would suspect head gasket by #6...have you noticed any water consumption..(white smoke/antifreeze) too much fuel would have black smoke and the amount you are fouling the plug is probably indicative of the short trips you are making with the car and never really burning them clean

[claybill]

the plug, tho rich is not extreme as you say. i would look at some other trouble...leaking head gasket would be #1..near low compression cyl..

smoke all the time is not rich carb...a rich carb will blow smoke on accelleration, not idle.

[Normspeed]

The outer edge of that plug looks wet, like oil is getting on it, unless that's just an optical illusion. If it's really that wet, give that liquid a good sniff. Oil or fuel?

[Frank Elder]

If it smells of both you are running rich enough to wash down your cylinders sending raw gas into your oilpan and preventing your oil ring from doing its job, don't forget to check the dipstick for fuel contamination.

[rolliejoe]

What air cleaner are you using?

Not using an air cleaner as i have to manually have to choke the carb, choke rod is missing.

The car hasn't left the driveway yet.

Car was running very rich until I removed the spring from under the step-up valve

basically eliminating the high speed circuit. Before plugs would turn dark black

with each run. I have a spark plug cleaner and have been blasting them. Before

stepup spring removal the smell of unburned hydrocarbons was very strong and

that smell would stick to you and your cloths.

All the plugs were wet like that, no smell though. Could that be oil that I was squirting in to the cylinders while checking compression. Though that oil would

burn off?

What am I looking for on the dipstick? Oil smells more like a dirty motor that fuel right now?

Water level seems to have stayed the same. I'll add a little water to bring it up

to a definite level.

The first startup the car didn't smoke. After that it has been smoking. The smoke

is like wiffs of smoke, not constant unless you bring the revs up. Like I mentioned

the smoke goes away when the idle is held at about 2500 rpm.

Are those compression readings okay besides #6?

[Californian]

Your readings on each cylinder should be at most 10& different, idealy they would all be even at anywhere from 100-120 Lbs across the board...

You may want to try a few drops of oil in no.6 & 5 cyl if it comes up its rings if it stays the same its a valve or the head-gasket with 75000 miles on it , original and never apart it may be time for a ring & valve job and check the bearings out with plastigauge...

There was a article in an old Popular Science mag,that showed an ilistration of a spark plug where the purcelein was removed and the spark plug was threaded 1/4 pipe to take a male air couppling and with each cylinder at TDC on compression stroke and with the air adapter in the sparkplug hole and compressed air was put to that cylinder and you listen through the oil filler ,the carburator and the tail pipe to locate your leak weather it be valves or rings or cracked piston...

But all said and done white smoke is usually steam and as said earlier it could be no 6 cyl head gasket ,now also if it is found to be that, you may want to look at the water distributor tube if you have a rusty cooling system and no 6 being the furthurest out on the line of the tube...

Tom (09)

[dirty dan]

The only thing that would cause white smoke from a car is steam from coolant or automatic transmission fluid burning. I agree that you most likely have a head gasket leak @ # 6 cylinder. One way to tell if the "smoke" is actually steam is that when steam dissipates, it all disappears near a certain point as it evaporates into the air. Smoke will linger gradually disperse.

[rolliejoe]

The white smoke has gone away, go figure. Still have some unburned fuel issues and wet plugs. Going to change out the plug wires, apply some air pressure to #6 to see were it's losing compression, change the muffler that's leaking and falling apart from the inside out, and try and get the car road ready to "clear the motor out".

Two observations:

No blow-by at the oil filler tube.

Fluid level in the radiator hasn't dropped.

thanks for all the suggestions.

[Frank Elder]

I would still check the gasket, mechanicals don't fix themselves. My 2 cents.

[Reg Evans]

Maybe re torque the head bolts. Maybe they are a bit loose.

[rolliejoe]

no loose head bolts, good thing to check though.

Got the motor to a point were the plugs don't foul right away.

What is happening now is that there is a miss proceeded by a puff of smoke. Total ignition tune up btw. Car doesn't like to idle so timing is reading 20 at what will keep the car running, 30 degrees total.

Another problem is all the freshly cleaned plugs are wet at the base, even the threads are wet. Doesn't smell like gas, could it be oil?

[Cpt.Fred]

it would be smoking blue like hell if there was this much oil in there, wouldn't it?

a flatty's head gasket isn't so hard to change, i guess... i would try that anyway. then you can take good look into every cylinder, check for damage and everything. imagine you get in half-fixed now, get on the road for a "clean-out" and end up sitting on the side lane with a blown engine:eek:

[rolliejoe]

did a leakdown test:

#1 blow by out the oil filler tube

#2 serious exhaust valve leak

#3 serious exhaust valve leak

#4 serious exhaust valve leak

#5 blow by out the oil filler tube

#6 serious exhaust valve leak and ring leak out the oil filler tube.

I guess I got a very tired motor.

[Normspeed]

I wouldn't be too discouraged by it. These old motors have seen a lot of use under rough conditions and many times got low quality oil with long periods between changes. The good part is, they can be rebuilt to better than new standards for a reasonable price, and if you shop around you just might find a decent running replacement motor ready to bolt in while you go through yours.