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Joined: Mar 2012
Posts: 240
B
'Bolter
'Bolter
B Offline
Joined: Mar 2012
Posts: 240
Hi all,

I am attempting to lean out my Carter W-1 on my 1947 3100 w/ 216 CID.

The '47 shop manual lists the standard metering rod as 67-46. That rod has "75-485" stamped on the opposite side. My interpretation is that 67/46 are sizes of the rod and 75-485 is the actual part number.

The manual lists the lean rod as 68-49. Does anyone know the Carter part number for that rod? Any idea where to get one? (Moderator: I know ISO belong in the parts wanted, but need the part number before I can post an ISO).

Thank you,

Bill

Last edited by BDammers47; 04/12/2021 11:28 PM.

1947 3100 Advanced Design

Never, never, never, never give up. - Churchill
Joined: Mar 2010
Posts: 1,660
B
Curmudgeon
Curmudgeon
B Offline
Joined: Mar 2010
Posts: 1,660
I hope Carbking steps in if I mess up on the info.

Bill it helps to identify the Carter W1 model you have. Also the altitude (higher--> leaner) where you live and whether are not you plan to run E10 gasoline or non-ethanol. If you are running E10, a lean rod may make your problems worse. Usually run one size richer because E10 has less energy per volume of gasoline. Also your truck may be a 3100 and not a 2100.

Carter W1 684S (from my book 1941-51 Chevrolet)

75-485 standard .067"-.067" to .062"-.062" to .060"-.046"

75-517 1-lean .068"-.068" to .065"-.065" to .064"-.049"

75-562 1- rich (no other info)

Any more questions, I would contact Carbking. He is a busy guy so be polite.


"Adding CFM to a truck will only help at engine speeds you don't want to use."
"I found there was nothing to gain beyond 400 CFM."
Joined: Nov 2002
Posts: 2,772
C
Carburetion specialist
Carburetion specialist
C Offline
Joined: Nov 2002
Posts: 2,772
Bill called, and we had a good conversation.

While I can furnish the rod in question, I don't think that is Bill's problem, and suggested he make additional tests, to which he agreed.

Seems the rich running engine came about after the installation of a PCV.

After rethinking our conversation, and the tests, I also think possibly the PCV may have too much of a vacuum source, and is sucking in too much oil smoke, and that is what is fouling the plugs.

In the FWIW category, normally if a rod needs to be changed (unless the vehicle is driven at 6000 feet or above), it will need to be RICHER due to modern fuel, not leaner.

Jon.


Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
If you truly believe "one size fits all," try walking a mile in your spouse's shoes!
The Carburetor Shop
Joined: Mar 2012
Posts: 240
B
'Bolter
'Bolter
B Offline
Joined: Mar 2012
Posts: 240
Buoymaker and Jon,

Thank you, Jon especially for the advice.

Dwell was off - point gap was over .018". I didn't check timing before adjusting gap, so I can't confirm how far off it was before adjustment. Timing was a couple of degrees retarded after the dwell re-set and warm-up.

Gap has been re-set and the timing re-adjusted, slightly advanced as suggested. The test drive went well - the part-load response is improved. I'll keep an eye on the plugs after I get a few more miles on and see if that improves the situation.

Thank you again,

Bill


1947 3100 Advanced Design

Never, never, never, never give up. - Churchill
Joined: Nov 2002
Posts: 2,772
C
Carburetion specialist
Carburetion specialist
C Offline
Joined: Nov 2002
Posts: 2,772
Great! Hopefully, the issue will disappear.

Jon.


Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
If you truly believe "one size fits all," try walking a mile in your spouse's shoes!
The Carburetor Shop

Moderated by  Phak1, Woogeroo 

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