joe_padavano

No, I didn't put a Chebby motor in my car. I did, however, finally throw in the towel on the 4GC carb on my 215 and get an Edelbrock 1403 (500 CFM). I have always been a proponent of keeping the original carb. Up until now I have never had a problem rebuilding a carb and getting it to run correctly (including the CCC Qjet) but this carb has kicked my butt.

Uncle! I quit!

I rebuilt the 4GC and set it up per the CSM. Car idled great, but there has been a continual accelerator pump problem. Sometimes I'd get a pump shot, sometimes not (with the associated stalling out). Opened the carb back up the first time, saw crud in the newly-cleaned float bowl, and dropped the tank to flush it out. Cleaned out the carb again. Same problem. Yes, the filter is new.

Took the carb apart again. This time I played with the accelerator pump. Interestingly, the pump well would sometimes not refill promptly after a pump shot, with the resulting suction from the throttle linkage closing causing the pump cup to roll out of position on the end of the pump body. Never saw that before.

I figured there was crud in the passageway between the bowl and the pump well, causing the well to refill slowly. I carefully probed the passageway with a piece of soft copper wire - no obstruction. I looked at the check ball on the inlet side of the pump (it was new with the rebuild kit and yes, I got the inlet and outlet ***** in the correct places). I replaced this check ball with another one from another rebuild kit. I replaced the formerly new pump cup with one from that other rebuild kit as well.

Still had the problem.

At that point I gave up. It's less than two weeks to Nationals and I do NOT have time for this. Advance matched Summit's price on the carb and it was delivered the next day. I bolted it on, and without the throttle linkage even being connected, the car started within seconds, once the float bowl had filled. Out of the box, with no adjustments to the carb yet, the car runs better than it ever did with the 4GC. Tomorrow's task is fabricating the throttle linkage rod and throttle valve rod. I'm pretty sure I have a way to make the Rotohydramatic TV linkage work without major drama. Now I just need to score some ball ends for the new linkage rods. Dorman lists them, but what are the odds anyone carries them in stock. Stay tuned.

Olds64

At least the Edelbrock is running correctly.

I ran an Edelbrock 750 on my 64 98 for a short time. I had to fabricate the TV rod with some all thread and turnbuckles I got at the hardware store. I also got a package of "ball ends" at the auto parts store. Keep us posted on the TV rod and throttle linkage.

That is interesting. Most of the auto parts stores I've been to don't price match to Summit, Jegs, or JC Whitney.

Oldsguy

I am sort of like you, preferring the original equipment over aftermarket if possible, but I am not a purist either. I can see the extra effort would be worth it on an extremely rare or valuable car (not dis-respecting your car) but sometimes a person just has to bite the bullet. Thinking about the 4GC, is there any possibility that there is a plugged vent in the upper housing preventing the pump well from filling? You mentioned cleaning out the passageway to the bowl but there might be another which allows pressure release on the top of the pump piston. Just thinking.....

What car is the engine in, your little wagon?

joe_padavano

Yup, the 62 wagon that I'm taking to Sturbridge. In debugging the carb, I've actuated the pump manually with the air horn off to see what's going on and the suction problem is still there, so it's not any kind of vent issue. In fact, if I just fill the float bowl with no accelerator pump in place, it sometimes (but NOT always ) takes a while for the pump well to fill up. I suspect there is something going on with the check ball sticking in the hole, but I just don't have any more time to deal with it.

Of course, NOW the problem is finding the little rod ends necessary to fab the linkage. NO ONE stocks this stuff anymore. I've spent the morning driving all over the county, going to three auto parts stores, a hardware store, and two tractor parts dealers. Amazingly, Advance Auto was most helpful. It turns out that McMaster Carr has what I need, and it will be in my mailbox tomorrow.

66ninetyeightls

When I made my throttle linkage I called every performance shop under the sun looking for the ball joint ends and nobody carried them. I ended up going to a local place called Princess Auto that also has a hydraulic section. The hydraulic section was FULL of different sized joint ends for the hydraulic cylinders. They were even the correct thread pitch. Ended up paying $3 each for really nice brass end joints.

Olds64

I think you can also get a package of them from Summit or Jegs. It is just a question of waiting on shipping.

aliensatemybuick

Hmmm, I am experiencing problems with the 4GC on my Jetstar I...though my issue is a surge condition at partial throttle. I have rebuilt it, adjusted the floats more times than I care to mention, investigated differences in base gaskets, etc etc. At one point, I thought i had the problem licked, but it has returned (or maybe I was deluding myself).

Being that my car is manual shift, the linkage won't be as much of an issue. I am seriously considering an Edelbrock unit. OR finding some old-timer who can get my 4GC to work properly (properly being a relative term, I think, when it comes to these things...I've NEVER liked the part-throttle feel of any car I've had with one of these carbs).

I guess I COULD change to a Q-jet also, and change the intake. But that'd probbaly be farther away from stock than I'd be prepared to move..

joe_padavano

I looked at those. The available kits are limited and are geared towards Ford and Chrysler applications. As I noted, McMaster Carr has the linkage ends and the connecting rods in stock, the price is less than from the traditional auto parts sources ($3 for the 1/4-28 size), and delivery is overnight.

The Stickman

Sorry to say it is the only way I licked my carb problems. Threw the Edelbrock on and the car has never run better.

Olds64

Those new Summit carburetors are supposed to be great. I almost bought one of those before I had Danny Sarvis rebuild my Q-jet. The Summit carburetors are square bore and designed to include benefits of both Edelbrocks and Holleys. You can adjust the float level without removing the air horn and they have no gaskets below the fuel bowl. You can add Holley jets and metering rods.

http://www.summitracing.com/parts/SUM-M08750VS/

80_cutlass

I have one and like it. Right now, the car isn't moving....killed my 350, but will soon have the same carb on top of a 403.

sb

74 Omega

I bought one as well, it is installed but I have yet to fire it up.....

Olds64

C'mon guys. Inquiring minds need to know if they work well.

66ninetyeightls

So go buy one install it and let us know!!!

Olds64

BTW, sorry to hi-jack your thread Joe.

joe_padavano

Yes, you did...

The Summit carb is actually a knockoff of the old Holley 4010, which itself is a knockoff of the older Autolite 4100. Actually, it appears that Holley no longer sells the 4010, which makes me think Summit has purchased the rights to that design from Holley. In fact, the castings for the Summit and Holley carbs are identical (the photo of the 4010 I posted is a marine version, without the vacuum diaphragm for the secondaries). I'll bet Holley even makes them for Summit.

Autolite 4100:



Holley 4010:



Summit:

80_cutlass

I actually used mine for several hundred miles before I killed my 350. I did (do) like it and will continue to run it. According to research I did online, Joe is right about the carb's anscestory, but apparently some of the shortcomings of the original(s) have been addressed:

http://www.fordmuscle.com/forums/ind...road-test.html

I had none of the issues the guy doing the review did with his....mine acted just like his 2nd one.

To continue the hijack.....since Joe has gotten into the discussion himself.

sb

Olds64

Thanks for that link. That review is very thorough.

BTW, that is cool info Joe.

joe_padavano

In an attempt to get this thread back on topic, here are some photos of the throttle and TV linkage with the E-brock carb. I had to use this E-brock air cleaner that I had lying around since the air horn on the 4GC is smaller than on newer 4bbls. I'll eventually modify the original air cleaner base so I can use that instead, but for now this is functional.

Here's an overview of the completed installation. Yes, I'm not thrilled with the rubber fuel hose either, but time is short. A metal line is on the list...



Here's a side view of the two linkage rods. Top is the throttle, lower is the throttle valve link to the trans.



Those familiar with the early sixties cars may recall that the 4GC has a fairly complex bellcrank arrangement built into the side of the carb. My original plan was to build a bracket that would hold that bellcrank next to the E-brock, in the original position. Unfortunately, the E-brock is considerably wider than the 4GC, so that wasn't possible. After doing a little more research, I found out that the whole purpose of the bellcrank is to act as an overrrider. These cars had a "feature" where you could fully open the carb throttle plates without forcing the trans into kickdown. If you then pressed harder on the accelerator, against a spring on the overrider bellcrank, the TV linkage would move further, sending the trans into kickdown. I've lost that function with the current linkage, but no GM automatic since this one has had that function anyway. We'll see how it drives shortly.

Here's an overhead shot for completeness. The linkage parts came from McMaster Carr (one of the all-time great models for customer service). I had to bend the upper rod so the two rod ends wouldn't bind against each other at closed throttle.



By the way, that air cleaner was a rusty mess that had been on a truck I had dragged home. I hit it with a Scotchbrite wheel in my air grinder, followed by etching primer and silver paint.

66ninetyeightls

Looks awesome Joe. Great stuff.

I might be seeing stuff but I can see through your passanger side fender!!!

joe_padavano

Unless you're real name is Clark Kent, I don't think so. There must be some illusion in that photo.

71 Cutlass

66ninetyeightls

Yeah I know its a funny name.

Just in case you think I'm joking.
http://www.princessauto.com/

Olds64

Joe, the modified TV rod I put on my 64 98 with the Edelbrock carb was essentially the same setup. It seemed to work well for me. I hope it works for you.

joe_padavano

Yeah, I just haven't had time to deal with it yet. In my exhaust thread I describe the other teething problems I've had to deal with this weekend. Two steps forward, one step back...

slodat

How did the carb work out? I'm considering buying the Edelbrock 500 from D&D Fabrications.

joe_padavano

It's working great. I still haven't got the throttle valve linkage completely dialed in, but that's due to a lack of time on my part. It shifts OK, it just doesn't downshift, so I have to do that manually. What does D&D get for the carb? It's $309 direct from Summit for the electric choke version.

rocketraider

Let me know how that TVR adjustment works out. There's times I feel like tossing my 4GC's in the trash too. I have a Federal-Mogul Carter AFB ready to try someday.

Dave Holt in CO made up a bunch of big car Slim Jim TV adjustment gages off an original BT-33 tool but I don't think those work on the F85. He's dlh61olds over on AACA if you want to check with him.

slodat

From his website:

joe_padavano

Again, I paid $309 for a 1403. Your call.

slodat

My thought was support the small guy that is supporting my 215. Plus, if he has it jetted correctly for my stock engine, I'm ahead of the game. It will be a month before I do this - leaving town for work in a few days.

66ninetyeightls

Maybe I missed is Joe but I haven't seen an update on this car in a while.

Please please please