Quick History:

Wife has had this car forever and refuses to get rid of it even though she will put no effort into starting it up once a week. I got pissed and just let her sit for several years.

Recently I decided If I can't get rid of it I might as well get it going. I'm not much of a mechanic but I drained the old fuel, replaced the plugs, PVC, and Air Filter.
It started right up, and I drove it 10 miles round trip and had the oil changed, seemed to run fairly well.

Decided to take it out on the Highway and really warm it up after about 5 miles it started to Backfire and Hesitate and got off the highway just in time before it died.

It starts right up, but will not sit at idle so I can shift into drive. As soon as I let up on the gas it dies. Also if I gas it to much and at a steady rate it starts to Backfire thru the carb. Tried replacing the Fuel Filter and sprayed some gumout around the Carb. Stays running without dying if I continually let up and then give it gas, revving it up and down.

I'd like to try and get it running good enough so I can at least drive it to a good Mechanic if possible.

I assume it's probably a Carb issue but what do I know, BTW it's a Four Barrel Rochester Q-Jet (1973 350)

Any ideals out there that this Noob can try? Starting to read information in my service manuals on these carbs and whats available on the web, but if anyone can start to stear me in the right direction it would be greatly appreciated.

Thanks
Jeff

Also can anyone recommend a good mechanic in the San Jose, Ca area

 

Here's the contact info for a very good, local mechanic:

Dave Herlinger
1230 Pear Ave. Bld.3
Mountain View... its off shorline
650-969-5351

More of a restorer but suposed to be very knowledgable.

There is also a person on the forum with the user name Lars. He's the guru on carbs. He used to rebuild them and is considered the best. He was on carb sabatical, but you may want to check with him as well.

 

Thanks CLV!

 

Their is a filter if you remove the gas line at the carb then the big 1" nut you will find a filter I think will be pluged up. This can cause the problems you are having. The tank may be full of rust from storage.

 

Thats the first thing I tried, thought for sure that was it, but no help

 

Replace the cap and rotor as well as the points in the distributor. You will need to set the dwell.

 

I got in on the Tach Drive HEI Group Buy, maybe that will help, Thanks.

 

Sounds like a fuel supply prob.

What did the fuel look like that was drained from the tank? If it was a yakky-gunch color, you may have a clogged tank sock,..the pre-filter that attaches to the end of the sending unit. Fairly easy job to replace on the Vette since the SU is on the bottom of the tank. But the tank may also need replacing if rust has taken over.

Also, this apparently happened on one of my 73's. The fuel line clogged up and Bubba by-passed the steel fuel line with 15 foot of 3/8" rubber fuel hose, tank to pump. Not smart.

Replacing the fuel lines require lifting the body to replace.

Let us know what transpires and good luck!

 

Might be gunk that broke lose in the carb itself clogging it, if you have some starter fluid shoot it into the carb when it tries to die and see of it picks back up

 

Thanks for the suggestions

Nether of my repair manuals mention a Fuel Sock is it the same thing as a "Gas Tank Sending Unit Strainer" ?

Would this be the part I'm looking for ?
http://willcoxcorvette.com/advanced_...rainer&x=0&y=0

Can you visually inspect it to see if it's any good?, I imagine in a 35 year old car I should just go ahead and replace it anyway. Edit to add: I did take a pek in the gas tank and it does not appear to be rusty and the sock is intack

I hope the Fuel line is ok, is it possible to blow compressed air thru it to try and clear it out?


Fevre, I would think the starting fluid thing would work, since if just before it dies after taking my foot off the gas, if I gas it again, it comes back to life what do you think?

 

Bump for a small video, Start, Rev up and down, then let off gas and it dies
http://video.google.com/videoplay?do...41227146&hl=en

 

By the way how did you drain the tank? I don't guess you kinked a hose or something

 

You are getting fuel because it will run at higher rpms. if fuel lines, sock or filters were clogged you would not run. the accelerator pump has dried up, very common when carbs sit for long times, which is why as you throttle up it coughs. the idle circuit is gummed up from sitting and most likely you have dried up and cracked gaskets. rebuilding the carb is actually pretty easy. I did my first one when I was 16, 35 years ago..... I mean 15 years ago.

 

croaker, I just siphoned it out.

hdpete98, had that feeling, I'm going to study up a bit to see if its something I want to tackle myself. I guess worst case if I muck it up it will only cost me double to have what I did undone .

 

If your not comfortable rebuilding your own carb, just take it off and take it to someone. There are pleanty of rebuilding services out there and any competent mechanic that knows thier older stuff could do it for you if you already have a mechanic. I would also check the distributor and freshen stuff up in there too. Plugs, wires, cap and rotor that old can't hurt to replace. As to your compressed air question you should be able to disconnect your fuel line and blow it clear if anything is on it. Just be sure to disconnect both sides.

 

Finally got around to removing the Carb the other day to be rebuilt.

Gee you think this missing piece of gasket had anything to do with it's problems

 

and why don't we think the fuel pump has crapped out???? it works just enough to get minimal pressure and fuel to the carb......... disconnect the line going to the carb and crank the engine with the coil grounded and see how much fuel is being pumped out...measure it in terms of qts per minute

 

Yes! Fix this first and run it before even thinking about rebuilding the carb!!!

 

oops i missed the update and YES

 

I decided that since the base gasket was in that bad of shape and due to the amount of time the car had been sitting to go ahead and have the carb rebuilt. After reading a couple books on Q-Jets I decided that this might be a little to big of a project for my skill level at this point and found a place in San Jose that rebuilds a lot of these. At least I got to the point were I have a basic understanding on how they work and could talk a little more intelligently with the Mechanic.

They seemed to do a bang up job on it, looks great, and after I bolted it back on and hooked everything back up she started right up and seems to be running fine with the small test drive I did. BTW, at least at this point I can Highly recommend Ace Fuel Systems in San Jose for carb work.

Thanks for all the advice , I think I'm becoming addicted to this site. Next up Brakes, installing my new HEI Distributor, and fixing an exhaust manifold leak, then on to a never ending list I'm sure.