carb question 72 vega 2bbl

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Re: carb question 72 vega 2bbl

Postby gotmud7 » Wed Apr 21, 2010 11:20 pm

Where can I find heavier weights or lighter springs? Gm parts counter? I'm thinking probably not.
The only Vega's that only had a little rust were the ones still on the assembly line.
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Re: carb question 72 vega 2bbl

Postby 73Vegaguy » Thu Apr 22, 2010 8:02 am

You can buy kits with different weights and springs from hot rod parts suppliers (Jeg's, etc.) for Delco V-8 (and maybe 6-cylinder) distributors. The springs will work for sure, and I'm pretty sure the weights interchange as well.
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Re: carb question 72 vega 2bbl

Postby cosvega76 » Thu Apr 22, 2010 9:11 am

Mark,

Take off the distributor cap and make sure you can move the rotor by hand. It should move one direction a few degrees (you should feel spring tension as you turn it), and when you release it, it should snap back. If it turns stiffly, or doesn't snap back, you need to remove the distributor, take it apart, and clean the varnish or corrosion from the shaft and breaker/reluctor assembly. If you're reluctant about taking the distributor apart, bring it up and I can help you with it.

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Re: carb question 72 vega 2bbl

Postby gotmud7 » Sat Apr 24, 2010 10:26 pm

I took out and completely cleaned out the distributor and weights and all today. Still no advance.

I saw my next door neighbor Larry was in his garage, so I walked over and asked him about the mechanical advance. He said he "probably has some lighter springs at the shop, but its not going to help since it sounds like I have a burnt valve." (He was in his garage, in his car- but the vega was idleing in my driveway) And then he says, "I probably have a complete small block at the shop I'm never going to use. Can I drop it off tomorrow?" Um,,,,"OK".

Now what? I've already got the Don Hardy mount kit. If I take it easy, can I still use the air cooled TH350? I'll have to go back and read some of the old posts. I'll need some headers once I know what kind of heads.

A little back story. Larry drag races (Larry Wolyniec- Competition Motorsports). Ever hear of the Chi-town Hustler? He was part of that. How about the Crusher Camaro? He did the suspension. NMCA? He used to build those cars. Bill Miller Engineering top fuel funny car? He worked on that for about 5 years every weekend. The Track-Meter? He invented it.
He keeps most of his cars out at the Billet Specialties warehouse in LaGrange, IL. When those guys get a car, they pull the small blocks and put in a big block.

I can't wait to see what happens tomorrow. Mark
The only Vega's that only had a little rust were the ones still on the assembly line.
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Re: Burnt Valve Test

Postby res0o7eb » Sat Apr 24, 2010 11:24 pm

I hate Queen, but "another one bites the dust".
Bummer that you are having so many issues with the 140 cu. in. SOHC I-4 that your only solution is to swap it for a V-8. :( That's drastic.

Before you begin the process of swapping the I-4 for a V-8, could you do the very simple burnt valve test as mentioned here? http://www.clubhotrod.com/forums/showthread.php?t=23527
Don't use money, though!
It would be good to definitively know that the symptoms you are experiencing with the Vega are indeed a burnt valve.

Thanks for posting your issues here, I learned a lot from you and everyone else who posted.

Also, the air-cooled automatic transmission in your Vega will not bolt up to a V-8 - the Vega SOHC I-4 engine used a unique transmission/bellhousing pattern.
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Re: carb question 72 vega 2bbl

Postby gotmud7 » Sun Apr 25, 2010 2:33 pm

Thanks for the test info. And for the Vega TH350 info. I am hoping that since I already have the TH350, swapping in a better one should be an easy fit.
The only Vega's that only had a little rust were the ones still on the assembly line.
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Re: carb question 72 vega 2bbl

Postby gotmud7 » Sun Apr 25, 2010 6:13 pm

My intention was never to keep the 140ci in this car. I basically was going to try and drive it the way it was until I could get it painted, and looking nicer. Then toss in a V8. I've been messing with this engine for the past 3 years now. I probably have less than 200 miles in 3 years.

In fact I even just put on the Heddman header and Edelbrock aluminium intake, hoping to get some more power until the V8 swap. I hope I can sell those and use the money for V8 stuff. I'll keep everyone posted. I think I'm going to go try and take my hood off. I hear that's a real PIA. Mark
The only Vega's that only had a little rust were the ones still on the assembly line.
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Re: carb question 72 vega 2bbl

Postby cosvega76 » Mon Apr 26, 2010 10:13 am

Mark,

Before you get into a large project, did you perform a leakdown test, or at least a compression test?

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Re: carb question 72 vega 2bbl

Postby gotmud7 » Mon Apr 26, 2010 10:44 am

Oh come on Chuck, you are such a buzz kill! No, I haven't done any of that. I can say that I am able to take something apart, see how it works, and resassemble it. But the diagnostic stuff I am not that good at. Don't even get me started on electrical.

I should probably do some testing on the engine to see if there is something really wrong with it that can be fixed (inexpensively). I do admit I hate working on an engine that might put out 100HP on a good day.

I made a list of everything I should do to put in a V8. I haven't priced everything out yet. But minimum I need a new transmission, radiator, headers, and so on...

Darn you Chuck. Just kidding. Mark
The only Vega's that only had a little rust were the ones still on the assembly line.
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Re: carb question 72 vega 2bbl

Postby cosvega76 » Mon Apr 26, 2010 5:49 pm

Sorry for spoiling your fun, Mark! One of the main problems with the V8 swap in an early car is making tunnel clearance for the larger bellhousing. It can be done with a BFH, but take a look at how Jeff Schwartz did his and see how much nicer (and more clearance) it is.

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Re: carb question 72 vega 2bbl

Postby gotmud7 » Fri May 14, 2010 8:35 pm

I bought a rebuilt distributor (Cardone) on ebay, $35 shipped. Removed the points and put on Pertronix Ignitor II today. Removed the radiator to take off the timing cover. Then put the radiator back in and filled it up. Set the timing again, verified we now have vacuum AND mechanical advance! What's that smell? Somethings burning! My ceraminc coated full length hedder (Hedman) is cherry red the last 12 inches of it. The high heat painted muffler about 12 more inches downstream is completely cooking the paint off of it. The radiator cap with thermometer says 80F.
I understand how the Vega engines overheat now and warp everything.
The only Vega's that only had a little rust were the ones still on the assembly line.
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Re: carb question 72 vega 2bbl

Postby gotmud7 » Sun May 16, 2010 7:04 pm

I took the Vega around the block yesterday. Had some pickup, but hesitated off idle. About half way I started hearing a "thump... thump.....thump" Not a tick. I thought part off the tire tread must have come off the front drivers tireand was hitting the bottom of the car each time around. Spead up, it went faster. Slowed down, it slowed down. I turned off the car and coasted thinking it was a valve hitting the piston. Still heard it. but it stopped when I put on the brakes. I looked under the car, but nothing. Started it back up and drove home with it Thumping again.
The only Vega's that only had a little rust were the ones still on the assembly line.
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Re: carb question 72 vega 2bbl

Postby cjbiagi » Sun May 16, 2010 7:37 pm

I'll admit I just started reading this thread. I must say you have the patience of a saint with this car.
Clyde.........75 Monza 2+2
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Re: carb question 72 vega 2bbl

Postby cosvega76 » Mon May 17, 2010 10:13 am

Mark,

Sounds like we need to get that car towed up to Marengo and schedule a Tech Day. :th:

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Re: carb question 72 vega 2bbl

Postby gotmud7 » Mon May 17, 2010 3:01 pm

I did a compression check. 3 cylinders came in between 125-135 PSI. I am not sure what is "normal" for a Vega. I was expecting in the 300 range The other, 2nd from front, measured in at 105 PSI. At the end I went back and rechecked it - 115. Then I went and shot 3 squirts of oil into each plug hole. All 4 cylinder readings went up by about 15-20 PSI each.
I ended up taking off the hood last week. I used a dremel and a small cut off wheel to cut the retainers off. I recommend removing the hood for everyone. There is just so much more room to work on it. Plus I have more light from the workbench to see what's going on.
I did the "burnt valve test" mentioned in the post above. Holding a piece of paper by the exhaust, it never got sucked back in.

I hate to spend much money on the 4 cylinder to take it apart, get whatever is wrong fixed, then end up with 80HP again. I haven't seen my neighbor around who offered that SBC. I am keeping an eye out for him.
Mark
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