Some carb advice for a new guy.

[MisterMinty]

I recently bought a 1968 GMC with the 283 Small block.
It has a 650 cfm Holley 4165 double pumper. The first issue is the manual choke on it was broken at some point and the PO wired it closed. Once I got it home I had to take care of some things on it before I could drive it so it ended up sitting for about 3 months.

I finally finished stuff up this weekend and got it running and driving again, but it was very hard to keep it running at first, it would only run for a couple of seconds at a time, then fire back up if you pumped the pedal then started it.

After a couple of different tries I noticed it was running longer each time and after about 5 attempts spaced 45 minutes or so apart it would run and idle fine.

After a short drive I turned it off and it would not start again, when I looked there was fuel puddled on top of the manifold. I tapped the bowls with a wrench, thinking a float might be stuck. Let it sit for an hour or so and then it fired right up and drove fine (no fuel on top of manifold).

So now my questions:
1.) I assume that the carb got a bit gunky or sticky from sitting for a couple of months. Does that seem reasonable given the description?

2.) does anyone know of a replacement manual choke kit for the 4165, or know if the one from Holley that lists the 4300, 4150, and 4160 will work with this carb? (the guy n Holley tech support did not seem to think it would work)

3.) a lot of my research indicates that the stock 283 would be happier with something in the 400-500 CFM range instead of the 650. I would like to hear thoughts on this as well.

I think it will cost around $140 for the choke replacement and a rebuild kit.
If a smaller carb would be better in general, then maybe replacement is a better route?

My plan for the truck is to try to get it to a good reliable driving state and have fun cruising it, not looking for fast, or lots of power. Low and slow is my style.

[Rich69shortfleet]

The problem keeping it running when cold is because you don't have a working choke system. It exists for a reason. If that 283 is stock, that is a fairly large carb for the engine but with a working choke should be able to be made to work. A vacuum secondary carb would be more forgiving in the driveability arena. Given how you want to drive and use it and if you want to keep this carb, make sure the secondaries aren't opening until fairly late in the primaries range of motion. Wouldn't hurt to have a good fuel filter involved in the fuel system. Do you know what jets and power valve are in the carb?

[geezer#99]

Pic of your carb and choke really would help.

[MisterMinty]

This is the side of the carb where the choke would be attached. the cable is still there going in to the cab, but the carb side has just a tiny bit of wire left at the end of the cable and is not hooked up.

The second picture is a closeup and you can see where the choke is zip tied open.

[geezer#99]

You’re missing enough parts to warrant getting a new carb.

[Steeveedee]

^ Yup!

[jayoldschool]

Too much carb for that little 283.

[MisterMinty]

Besides the choke, what else are you seeing missing?
A lot of people seem to like the Edelbrock 1404 for the smaller engines, that is the direction I am leaning.

[Sicklajoie]

A 500 cfm carb would be a good fit for a 283. A 650 is too much carb for that engine.

[geezer#99]

Originally Posted by MisterMinty

Besides the choke, what else are you seeing missing?
A lot of people seem to like the Edelbrock 1404 for the smaller engines, that is the direction I am leaning.

Secondary accelerator pump linkage is missin.
I’d steer clear of an edelbrock unless you really want to learn a bunch more about carb heat, fuel pressures, secondary bogging etc.
I’d go with a Holley 600. It’s a vac secondary so not to big.
Like this.


https://www.ebay.ca/itm/358098653001

[MikeB]

FYI, the carb is a Q-jet replacement. There seem to be lots of different list numbers. What's really confusing in the exploded view below shows a secondary pump diaphragm, but also vacuum secondary housing, diaphragm, lever, etc. Below is some Holley documentation. Figure 1 shows you where the "list number" is stamped. That will give you further info on that specific carb.

https://documents.holley.com/199r8340-1rev.pdf

On another note: Yes, a stock 283 needs nowhere near 650cfm. However, I'm not sure your secondaries are even working! Holley does make a rebuild kit for your carb, but it doesn't include any external parts that may be missing. If that's a Q-jet manifold, you will need an adapter plate for a square bore carb. And I would be leery about buying a Chinesium Holley rip-off.

[MikeB]

Just found this, which should help you to determine what is missing: It's several photos of a 4165 series, list 0-6210 carb. It's clearly a double pumper, not vac secondaries. The vacuum diaphragm you see is a choke pull-off.

https://www.oreillyauto.com/detail/c...tor/hly0/06210

[MisterMinty]

Thank you all for the replies. Looks like a new carb is up next. Now I just need to get to the bottom of the Edelbrock vs Holley debate!

[MikeB]

Originally Posted by MisterMinty

Looks like a new carb is up next. Now I just need to get to the bottom of the Edelbrock vs Holley debate!

Yes, lots of people feel strongly each way! I used several of each over the years, from a 450cfm Holley Q-Jet replacement to a dual quad Edelbrock setup, which has worked exceedingly well for more than 5 years now. In fact, I did another one last year for a 302 Ford, and it's also been working great.

My favorites have been a Holley VS 650cfm 4150 series, and my truck's current carb--an Edelbrock 650cfm AVS2. Many times the smaller carbs, like a 390cfm Holley cost more than a 600cfm Holley like the 80457. Same is true of an Edelbrock 500 vs 600. If the truth be known, a stock 283 may not draw in enough air to open the secondaries of 600cfm carb, or maybe even a 500.

Edit: Have to add that that Edelbrock is often and bolt-on-and-go carb, where all you have to do is set idle speed and idle mixture. Holleys typically need a little more tuning, sometimes squirter, jetting, and power valve changes. There a lots of good resources for learning what components effect various carbs' operations. But the Edelbrock owners manual takes first place. https://www.edelbrock.com/media/wysi...ers-manual.pdf

[Carl Spangler]

Originally Posted by MisterMinty

Thank you all for the replies. Looks like a new carb is up next. Now I just need to get to the bottom of the Edelbrock vs Holley debate!

Well, it was nice to meet you. Leave a trail of crumbs on your way down that rabbit hole.

[Rust_never_sleeps]

Originally Posted by MisterMinty

Thank you all for the replies. Looks like a new carb is up next. Now I just need to get to the bottom of the Edelbrock vs Holley debate!

<cough cough> quadrajet <cough>

[GSP7]

Looks mint, full race to me

[MikeB]

Originally Posted by Rust_never_sleeps

<cough cough> quadrajet <cough>

Well, since he's already got the manifold...

['68OrangeSunshine]

Originally Posted by MisterMinty

Besides the choke, what else are you seeing missing?
A lot of people seem to like the Edelbrock 1404 for the smaller engines, that is the direction I am leaning.

I have a souped up 292 L6 [Bored .030-over, Crane Cam, bigger valves, Offy intake, Clifford headers, etc.] and I run the Edel-1404 w/manual choke on my '68 C/10 Stepside.
Great carburetor.
I ran a Holley 4160, R8007, 390 CFM for 25 years, but it was always a pain -- blowing out power valves at every backfire, and needing constant tuning.
The Carter AFB design is much better for me.

[Rust_never_sleeps]

Originally Posted by MikeB

Well, since he's already got the manifold...

Yah, I'm just being a troll

[D.PASSMORE]

Advice: Carbs are not plug and play. You will need to dial them in. Combination of jets, needles, timing and I use a Air/Fuel sensor with gauge.
Or periodically, you get lucky and they work for your set-up right out of the box.

[MARKDTN]

I don't have much to add. 650 double pumper is way too much for a 283 as said. I'm a Holley guy so I would lean that way BUT a properly built Quadrabog-I mean Quadrajet-is a very fine carb when done right. If you can find a reputable shop to build/sell you one that may be the way to go. Auto Zone used to sell Holley USA rebuilt Q-jets but the quality has gone downhill as I think they are not done in KY any more. I'm going to throw out a new one. Do you really need a 4bbl? What about a Holley 500 cfm 2 bbl? Would depend on how that intake is configured but might work.

[tim_mc]

Just to add what Mike B. said, I use the Edelbrock AVS2 with its annular flow primaries. They are relatively easy to tune. No cold start issues at all. I see there's a 500CFM version (Model 1901 or manual choke 1902), so that would probably do the trick. Reviews look good. But, as always, it's easy to spend other people's money! Looks like they're still made in the USA too.

https://www.summitracing.com/parts/edl-1901
https://www.summitracing.com/parts/edl-1902

['68OrangeSunshine]

The difference between the old Carter AVS and Edelbrock's new AVS2 is in the Metering Rods and Jets. Carter's AVS used three-stage Rods and Jets -- allowing mid-range tuning.
The Edelbrock AVS2 uses the same two-stage style Rods and Jets that are used on their Performer [AFB Clone.]
AFIK 3-stage Rods and Jets have entirely disappeared.

[Steeveedee]

Not sure what you mean by 3-stage metering rods. I bought an AVS2 and a calibration kit (slight surging at part throttle). The rods in the kit are small at the tip, taper, and further up have a step. I suspect that that largest diameter doesn't actually enter the jet, given the carburetor configuration? I haven't changed anything yet, as it's a real mother female dog to get up there when I'm using a cane. At least I got the carb on and the truck running.