Author Topic: Edelbrock Carb Rebuilt!  (Read 2684 times)

Offline devildogmech

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Edelbrock Carb Rebuilt!
« on: April 29, 2018, 06:59:27 PM »
Hey all,

My new to me 79’ C-10 had a bum edelbrock Carb. I tore it down and rebuilt it.

It’s AMAZING what you can do with a YouTube video!

So, it’s running....... just not right.  When I put it into gear, it Boggs way down and almost dies. It’s really touchy to get going down the road.

I THINK I might need to step up the springs inside the pump... I’m pulling 10in/hg at idle, so that puts me up a spring rate.... I think.

Anywho, let me know if you have an idea!?!?

FYI, timing is set at 12’ BTDC without the vacuum advance.

https://youtu.be/UgDP82j0S_0



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Be good, but not too good.

Offline 1967KaiserM715

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Re: Edelbrock Carb Rebuilt!
« Reply #1 on: April 29, 2018, 07:28:31 PM »
I don't go by hg, but typically if you have some off idle issues and you think the idle mixture is good, then step up a size in springs (I try to go as large as I can, then work my way back down until I get acceptable performance) leave the accelerator pump rod in the middle position (or factory stock, typically is middle) and adjust that last if needed.

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Offline Rattler12

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Re: Edelbrock Carb Rebuilt!
« Reply #2 on: April 30, 2018, 08:27:27 AM »
IMHO ?.........edelbrock carbs are junk right out of the box. Better off with a Holley or even a rebuilt quadrajet. Once again just my opinion
83 C-10 shorty 454, 5spd, 3:73 posi

Offline VileZambonie

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Re: Edelbrock Carb Rebuilt!
« Reply #3 on: April 30, 2018, 07:55:41 PM »
Edelbrock carburetors are good carburetors, the problem is most people run them right out of the box without tuning them to their rig and think turning the idle mixture screws qualifies. Holley carburetors are more prone to failures with potentially serious end results, engine fires and flooding being a common issue. Any carburetor can have issues especially with today's cheap gas. If you take the time to setup and tune the whole package you can get good drivability and performance from most popular carburetors.

Check your fuel lines and see if there are any collapsed or kinked hoses. Did you remove the jets and clean all of the passages, replace needle and seat? Set the float level and drop? Did you ditch the little sock filters?
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Offline AZ4X4SQBDY

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Re: Edelbrock Carb Rebuilt!
« Reply #4 on: May 13, 2018, 02:16:55 PM »
I recently was asked to look at a neighbors '72 Corvette that his grandson had installed a Edelbrock 1405 carb on about 10 years ago. It ran ok when he was done but for the past couple of years it ran similar to what you are describing.

Vacuum gauge was all over the place, loading up the plugs, would not idle under 1100 rpm. Per Edelbrock and the internet, blew the idle passages out, no change. Tried to kit it, wrong kit, threads on needle and seat assembly wrong, obtain correct Edelbrock kit with new floats and accelerator pump. Installed and lowered float level, no change. Installed friends Edelbrock carb on his car, it runs and idles correctly.

The fourth time taking it apart, I am double checking everything because it will not idle or move off idle smoothly, with the carb still on the engine, I removed the carb top. The float bowls still had fuel in them, I sprayed cab cleaner down one of the jets........

Bubbles came out of the floor of the float bowl, at first I was thinking it was nothing but then decided to coat the floors of the float bowls with JB weld because if it was bubbling one way, it would draw fuel out of the bowl under vacuum the other way. Let it sit overnight and reassembled the carb.

It started and ran well, set the timing and adjusted the mixture screws. My neighbor jumped in and drove away. After about 20 minutes I started looking for my car keys to go looking for him, then I see him drive down a near by street. After about 45 minutes he comes back and says it never ran this well and he was grinning from ear to ear.

Bad casting? Internal corrosion from alcohol in gasoline? I don't know. This is the first time I ever worked on a Edelbrock carb, I had done a ton of Quadrajets and Holleys back in the day so I understood how it was supposed to work but never suspected this. I also didn't see this solution on the internet either.

I am not saying this is your issue but just my personal experience and a solution I found, good luck.
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Offline Rattler12

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Re: Edelbrock Carb Rebuilt!
« Reply #5 on: May 14, 2018, 08:30:11 AM »
My main gripe with edelbrocks is that you drive the vehicle one day let it set for 3 or 4 and the fuel bowl is bone dry. I don't know if its leak down or evaporation. I have a holley on my 83 and after letting it set 3 or 4 weeks you press the pedal to the floor once and it starts right up. I just replaced my LAST edelbrock with a rebuilt quadrajet………….Anybody want 3 edelbrocks :)
83 C-10 shorty 454, 5spd, 3:73 posi

Offline devildogmech

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Re: Edelbrock Carb Rebuilt!
« Reply #6 on: May 29, 2018, 06:19:38 PM »
So, I'm an idiot.... Nothing I didn't already know.

One of the Vacuum caps popped off.... Simple fix.

Then it ran OK, just not great. Changed the step up springs and it ran AWESOME! Yay, done, right? HAHAHAHAHA.

NO

Tootiling around town it starts running like ass.... Died at the busiest intersection in town...UGH.

Turns out #8 spark plug was completely fouled. I cleaned it and it ran fine.... So, now I have to do valve seals....

All this for a motor I have no intention of keeping.  :o

You guys are AWESOME, just have to say.
Be good, but not too good.

Offline 75gmck25

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Re: Edelbrock Carb Rebuilt!
« Reply #7 on: June 30, 2018, 06:14:01 AM »
When you replace seals I assume you will leave the heads on and use compressed air or rope in the cylinder to keep the valves from dropping down. 

I recently used this valve spring compressor and was very pleasantly surprised how simple it is compared to the cheap ones you borrow at Autozone.  I had to use this type because I had new heads with dual springs and the cheaper spring compressors would not work to compress both springs.  However, now that I've used it I would never go back.
https://www.amazon.com/Proform-66784-Valve-Spring-Compressor/dp/B000630J84/ref=sr_1_3?ie=UTF8&qid=1530357048&sr=8-3&keywords=proform+valve+spring+compressor

Bruce

Offline Rattler12

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Re: Edelbrock Carb Rebuilt!
« Reply #8 on: June 30, 2018, 08:01:19 AM »
Those are indeed good...….. one resides in a place of honor in my shop
83 C-10 shorty 454, 5spd, 3:73 posi

Offline devildogmech

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Re: Edelbrock Carb Rebuilt!
« Reply #9 on: June 30, 2018, 11:01:54 PM »
Oh man! You coulda said something a couple of weeks ago! I just bought one of the simple lever models. $10. Did the trick.

Did the valve seals... There were NONE!

Also replaced the Coil. It was messed up. Now she runs like a dream..... Cant wait to do that 5.3 swap!
« Last Edit: July 01, 2018, 12:25:37 AM by bd »
Be good, but not too good.