princeRed72

I have a friend who has a 63 split with 327/340 hp 4spd. He totally rebuilt the car and it is all original from what I am told. It does not want to stay running at idle. He keeps having to play with the gas as it seems to flood out. Once he gets moving of course it runs fine.
He told me this has been this way since the rebuild which has been some years. He is tired of fooling with it as his wife is having some health issues. I want to get it running good for him.

Again the car is all stock. He told me when he first got it running and tried to tune it they ran out of adjustment with the distributor.
First thing I want to do is make sure the engine is time correctly so I will rest distributor and engine to TDC.
Then I want to look at the carb. Original style AFB carb. The shop he has it at know told him the carb is shot. probably cracked inside or bushings shot on the shafts. This guy wants to tear the engine down to see what cam is in it. He claims he put a Holley on the car and it is running better but still not right.
Anyone have any recommendations on where to get the carb rebuilt or a rebuild kit? Any other suggestions? I already have Lars paper on timing.
I need to convince my friend to get the car out of the shop he has it.

bluestreak63

From what I hear Daytona parts is a good rebuilder and they sell rebuild kits if you want to do it yourself.

But it sounds like you need to convince your friend to get the car out of the shop before it's too late.

You can also get a rebuild kit from Napa too...echlin I think is the parts maker.

Boyan

What dist vac adv can is he running?

SWCDuke

I don't think I'd make an even odds bet that the engine is "all stock".

With the proper 12-16 degrees initial advance the VAC should be about halfway between interference points and the window near perpendicular to engine centerline. Verify plug wire indexing IAW with the '63 shop manual, and proper installation and assembly of the dist. including orientation of the gear.

Tearing down the engine to verify the cam is ridiculous. A lobe lift check at the pushrod can be used to verify that it is any OE mechanical lifter cam, Duntov, 30-30, or LT-1.

Like Boyan said the ID of the VAC is important. Also get a manifold vacuum reading at 900 idle speed.

This shop sounds like Bubba owns it.

Duke

Bluestripe67

Get the guy to get the car out of that shop before it's too late. Dennis

63 340HP

The inability to set timing should have been the first clue that the expert advice was suspect.

I would start with correct timing. The distributor may need the cam gear reinstalled 180 degrees (a 1/2 tooth change) before you find the timing can be set correctly with the limited room. Take your time, and get the 3000 rpm advance around 36 degrees. That position will help before Lars tuning.

The AFB probably only needs cleaning, gaskets, and an accelerator pump. If it is leaking gas, the needle and seat are stuck open with crud. I would not use a Holley, the AFB looks complicated by is less prone to cause trouble than the Holley and will perform well.

Let us know of any updates?

If a rebuild is needed there are cam options that provide the low rpm power of the original Duntov 097 cam, with the high rpm performance of the LT1 cam, compatible with stock diameter valve springs and a 91 octane friendly flat top piston configuration. I am currently finishing up rebuilding and improving my cars original RE code 340hp 327, so the process is fresh in my mind (if suggestions are welcome).

Frankie the Fink

All of the above. Sounds like these are basic home hobbyist style maintenance and tune-up tasks we've all done in the garage. I haven't seen many Carter carbs that were on a running engine that couldn't be brought back to original trim and function. The distributor adjustment range "running out of room" sounds typical of a one (or more) tooth off scenario and the reason the car is running like crap.

This is a case of the blind leading the deformed and your pal should retrieve the car and get some competent help. If these guys tear into that engine I'm seeing an unnecessary repair tab in the high 4-digit range in the future.

When I see these shops that can't make a "meat and potatoes" small block chevy engine run with original components its a huge red flag.

Cripe's I'm having a "Donny Brass saves the day" flashback

<DEEP BREATH> Daytona Parts does indeed make excellent carb rebuild kits and a '63 Shop Manual can guide you through distributor/timing issues...

If you're in a hurry a NAPA Echlin kit or Walker kit will also work.

phil2302

FIrst thing needed is to get that car home before the engine is taken apart for no good reason.
Secondly recommending that someone get a kit and rebuild their own carb when their history suggests they depend on bringing cars to a shop for tuning, carb, timing issues is a recipe for disaster.
The problem sounds fuel / carb related so maybe take the carb off and put a new Holley, Edelbrock performer or QJ on it and see how it runs. If that solves the problem leave it on and keep the Carter on the shelf or take the Carter to a qualified rebuilder and if originality is important put it back on. This approach will cost hundreds vs the thousands that shop is about to soak the car owner for.
GM didnt like the Carter either.

Frankie the Fink

I think the OP (friend of car owner) was sorta offering to do the rebuild...and swapping on non-stock carbs to create yet another variable to deal with is not the way I'd go...but to each his own.

phil2302

Dont see how using a carb change as a diagnostic method is creating a variable. Here is my real world experience with it.
We had a 65 coupe my son and I did a body off resto on about 20 years ago. It always ran like crap with a carter on it. As part of the resto I rebuilt it but no change it still flooded stalled rough idle ran rich then lean fouled plugs etc. I brought it to Allstate Carb here in Islip NY. He went through it made some minor adjs to it but told me my rebuild looked fine. Still no change. As a diagnostic method, he offered to loan me a QJ to try on the car. It ran beautifully.
From that I knew where the problem was and could choose where to go from there.

tbarb

Get the car home and start with basics first, make sure the tune is all stock. I could go on and on like everybody else could but you have to back up and start over.

Now that these carburetors are near 50 years old part of a good overhaul is to verify all jets, air bleeds etc are the stock size, that information is out there with the internet.

SWCDuke

An unmodified 340 HP distributor provides 24 degrees max centrifugal at 4600. So if you use a dial back light to set total WOT advance to 36 at 3000, what will it be at 4600 and above?

This "set the timing at 3000 myth" just won't die. I've pointed it out many times and regular readers of the CF should know better.

Total WOT advance has to be set A FEW HUNDRED RPM ABOVE THE POINT OF MAX CENTRIFUGAL, and this will vary depending on the engine and whether or not the centrifugal curve has been modified, so one should ALWAYS determine the RPM where centrifugal achieves maximum value.

For unmodified distributors max centrifugal is achieved from as low as 2350 (365/375 HP) to as high as 5100 (L-79, late 300 HP and some big blocks).

So check OE specs and then use a dial back light to verify the point of max centrifugal because it may have been modified in the past 50 years. Then set total WOT advance in the range of 36-40 a few hundred RPM above where you determined max centrifugal is all in, VAC signal line disconnected and plugged, of course.

Duke

63 340HP

My apologies SWCDuke.

I should have said set the timing at 36 degrees above the maximum rpm where you see the timing stops changing (the RE spec is 4600 rpm but with old springs and wear, and modifications, it must be verified).

I personally hate dial back lights, and prefer timing index marks and a standard timing light (timing tape works too, but I have seen too many 6" tapes on 8" balancers, or worse, etc.).

IMO, if you cannot read the timing at the tab and an index mark on the balancer... you need to teach a young person with good eyes how to properly set timing while they help you tune your engine. Some helpful modern tools (like a dial back light) obscure the mechanical fact and intuitive feel of learning how timing advance works by witnessing the plug fire 30 degrees before top dead center. It does not matter if that young person is fifteen or fifty years old, learning by witnessing the spark timing advance process in real time at the mechanical location point of ignition triggering, helps the next generation (to learn the basics needed before slapping on that modern EFI & Ignition system with Bluetooth smart phone interface that totally obscures an intuitive feel).

MOXIE62

For what it's worth, the AFB is an easy carburetor to put a kit in. You just have to on reassembly take your time installing the metering rods. They have to be in perfect align to fit in the jets. I got my kit at NAPA and there were gaskets left over but again take your time and pick the correct gasket.

Frankie the Fink

OK - I'm having a senior moment or a reading comprehension issue.
Somebody wanna tell me how you set WOT advance on a running engine ?

If I have 36 degrees (initial + centrifugal) "all in" and work with the springs to make that happen at 2700 RPM or so; how do you perform the bold-faced part ?

I'm missing something with the terminology apparently..

SW Vette

In that case, check your timing at around 3000 rpm, where you're sure it's fully advanced. Just add a few hundred rpm to the "all in" number to be sure, is how I read Duke's instructions.

tbarb

Frank,

Duke is saying to be certain that the total WOT advance (36-40*) is set at a RPM where the centrifugal is finished advancing. I am not a believer of sticking my face in a engine compartment with a engine spun up so high. One time I did that and had a water pump break up because someone had installed a fan clutch with a 3/4" pilot hole on a pump with a 5/8" pilot.

What I do is mark the damper at 12* increments to get to the 36* point and remove the springs in the distributor and all it takes is maybe 1500+-RPM's and set the timing with a regular timing light.

Works perfect every time, when I am finished I re-install the springs and I'm done.

Frankie the Fink

Thanks (and SW_Vette too) ... I got it. I thought I was missing out on some secret Buck Roger's timing technique after all these years

I wasn't

SWCDuke

Let's look at a couple of examples.

The OE centrifugal curve on my 340 HP SWC is 24 @ 4600, so to set total WOT advance with a dial back light I would have to verify this by revving the engine to this level and then a few hundred more to be sure that the advance is all in. If it is all in at 4600, then I'll set it at about 5000.

BUT, circa 1965 I installed the 365/375 HP vacuum advance (The OE 201 15 does not pass the Two-Inch Rule, which resulted in idle instability and stalling) and centrifugal weights and springs that bring in the full 24 degrees centrifugal at only 2350. Of course, that was way before the advent of dial back lights, but now with this centrifugal curve I only have to rev it to about 25-2600

Some OE centrifugal curves aren't all in until 5100, so when recurving such a distributor I'll inspect the weights and springs, and if they appear OE I will rev the engine up to at least 4500, and if it's still advancing at that point it's time for lighter springs.

Some distributors have up to 30 degrees centrifugal such as many big blocks and the '66-'67 300 HP engine, 30 @ 5100. Installing the silver or gold springs from the Mr. Gasket 928G spring kit brings it all in by about 3500. The curve is non-linear, so most is in by 3000, but there's another 2-3 degrees added by 3500, so I set the total WOT advance, usually in the 38-39 range, at about 4000.

Once I've set the timing at an appropriate speed above the point of full centrifugal I'll blip the throttle up to at least 5000 (6000 on SHP engines) to verify that there is no further advance such as might occur if there is a deteriorated rubber bushing on the advance limit pin.

If a test drive including loading up the engine at low revs in top gear climbing a grade exhibits no detonation, it's good to go.

Duke

mjdart

Make sure the valve lash is set correctly when engine cold with tight settings it will be OK, but as the engine warms the clearances will tighten and drop the rpm dramaticaly > 400 rpm. Not sure if the 63 L76 has the same cam as my 64 L76.