1977 Dodge American Clipper

[kwilly]

Hi all

At idle the PPM on my Clipper tested at 340 and max is 300 where I live.

Any ideas on why it's so high? Should I look into having the carb rebuilt?

Thanks all in advance

[n2zon]

Welcome to irv2.

Please be more specific. From the year, I infer ppm of CO, but it could be NOx emissions. And, where to you live? CA?

Finally, if it's CO, check the choke to make sure it opens all the way. I cannot recall at this point whether Dodge used heat risers, electrically-heated bimetallic strips, or hot water heated bimetallic strips for their chokes in '77. All, however, can eventually fall out of adjustment or fail. Also, you probably have an idle mixture adjustment. Lean it out, engine warm, until it starts to stumble, and then turn it toward rich *just* enough to make the engine run smoothly.

[Skip426]

Welcome to iRV2.

What engine in your RV 360/400/440 ?

How old was the fuel in the tank when tested ?

Was the test ok above idle ?

[kwilly]

1977 and yep CA. Thanks for all of the info, I keep hearing about an automatic choke.
Thanks alot

[kwilly]

440. That I dont know. And yes I believe so. The only fail was the idle test.
Thank you!

[Skip426]

The early Dodge 360 CuIn engines had a problem with the exhaust passage through the intake ( meant to provide the heat to release the choke ) plugging up , so the choke would stay on, even with the electric heat coil operating .
Removing the intake manifold and chiseling the carbon out of the manifold and heads was required , the passage also was the supply for the EGR valve .

EDIT : I see you posted 440 while I was typing , OK I'll do some head scratching about the T'Quad carbs and idle circuitry .

[kwilly]

Thanks!

[kwilly]

Just came across this part wrapped in foil

[n2zon]

Originally Posted by kwilly

1977 and yep CA. Thanks for all of the info, I keep hearing about an automatic choke.
Thanks alot

Right, so warm up the engine, remove the top of the air cleaner, and look at the choke plate (the topmost one). It should be vertical. If it is, the next question is whether the engine was fully warmed up when you got the emissions test.

[Skip426]

Originally Posted by kwilly

Just came across this part wrapped in foil

Exhaust modified from single to dual , with blue bottles for mufflers , I'll bet that the 440 has quite a bark at highway speed.

Follow the tube up to see where it's heading to , there was never anything like it from the factory .

[Skip426]

Here's photo of the factory carb for your 440-1 .

The choke plate ( yellow arrow ) is in the wide open position .

Idle adjustment screws ( red arrows ) .
If the idle mixture screws aren't visible , some CA emission carbs had sealed mixture screws . If your carb has sealed mixture screws , take a close up picture of the front of the carb and post it here and I'll tell you what you have to do to access them for adjustments .
I started working at a Chrysler/Dodge dealership in 1975 and my new 79 PU had one of these carbs and I kept the truck for 14 years .

EDIT: Just had a thought ; Have you had the RV long enough to know if the engine is using any oil ? More than a quart in 2,000 miles ?
Engine oil going through the combustion chamber , either from rings or valve seals shows up as high emissions at a tail pipe analyzer.
Have you changed spark plugs ?

[Ron Dittmer]

Is it practical to install a manual choke like a lawn tractor has? I did that many years ago on an old tired 1981 Toyota Corolla. I have to admit it was not nearly as nice working as the original choke before it fell ill, but it did start the car and once warmed up, the car always ran fine.

Search for "manual choke kit". There are many universal kits available.

I don't know if an emissions inspection would pass such a modification.

[bigb56]

Originally Posted by kwilly

Hi all

At idle the PPM on my Clipper tested at 340 and max is 300 where I live.

Any ideas on why it's so high? Should I look into having the carb rebuilt?

Thanks all in advance

Back in my old big block days I sometimes had a hard time passing, what I would do is lean the idle up till it started to stumble just a tiny bit, run it through then richen it back up. Don't you have a shop that can adjust it while sniffing it? Sometimes it take a combination of idle speed and idle mixture to get it to pass. Mine would never pass when set to the book, always had to adjust for emissions then put it back afterwards so it would run right.

[kwilly]

Originally Posted by n2zon

Right, so warm up the engine, remove the top of the air cleaner, and look at the choke plate (the topmost one). It should be vertical. If it is, the next question is whether the engine was fully warmed up when you got the emissions test.

I’ll do this tmmrw, or try lol. I drove it straight to the smog shop from my home only a 7 minute drive so no.