Hi

Im having problems getting my Corvette to run right! The car hard to start...The Engine blowing black smoke through exhaust running like crap and back firing...The car has virually no pick up...

Any suggestion to tackle this problem?

Pete

 

General tune up, points. condenser, plugs, set timing and adjust carb.

 

Hi Jack

Yeah I thought so.....Im glad i paided $$$ just to have that DONE!!!!

 

Your choke may not be opening. Is it the stock carb or aftermarket?

 

I know the feeling well!
I got tired of paying mechanics big buck to work on my car, even basic tune-up and without fail getting the car back running worst than it did before I dropped it off to them!

If you gave the car to a mechanic to do a "tune-up" one of the first things I'd check is to see if they plugd up your vacuun hose from the carb to the vacuum can. Without fail, EVERY time I took my car to a mechanic they plugged the hose with a little ball bearing because "your timing was too high and this lowers it".

Well, gee jacka**, i KNOW the timing was too high, that's why I gave you the car and asked you to recurve my distributor.........

I finally gave up and that's when I started to learn how to do it myself! Guess what, I can screw up my own car for a lot less money that I was paying them to screw it up and it's actually less screwed up than when they would do it.

Nowe, to your cars problems. The backfiring and black smoke through the exhaust sounds like your carb is running too rich.
lack of power sounds like probably timing.

Do you have a vacuum gauge and dialback timing light? if not, it's time to go get one. Believe me, if *I* can learn how to adjust my carb and set my timing than ANYONE can.
I'll bet that if you have these tools or once you get them we can get your car running good again in a short time.

 

Carb tuning is a lost art. Unless you find some guy that had gray hair and is actually working in the shop, forget it.

I decieded I was not going to be held a victim anymore and bought some books.

What year car, motor, options, etc????

It sounds like a rich condition, which can happen for many reasons. What carb do you have?

Mark

 

Hello All

Hi Barry K...I have a recently rebuild "stock" 3461S Carter Carborator..This carborator was bought buy me for 500 bucks and supposeable rebuilt..I had to get it rebuilt again because the gasket was dry rotted..(another $$340.00 bucks) Its a 327 300hp engine

I have headers on the car...So the choke is not being used...Idle is set high so it wont foul the plugs...Usually idles around 1800 2000 rpms when cold...Pulled the plugs they were black((cleaned (regapped) put back in)...So, I know its running rich...Also popping and backfiring sometimes a loud pop..or bang (blakc smoke)...Im having problems starting it..It hard to start have to cranking it alot..I did flood it once already..I brought it in 3 occassions still not fixed right now im being told its a "drive train" problem...The mechanic i use says he not sure whats wrong...Maybe valvetrain or cam problem...$$$$

When I drive it it feels like it driving on 4 clyinders no "get up and go" (bogging down bad feels like losing compression)) Will barely run..then sometimes i get burst of running right... I dont like to drive it many places because its unreliable..Im getting tired of getting nickel and dimed to death...I put alot of money in this Corvette and yet it still doesnt run right...

Very frustrating. I have a timing light...Im not sure where to begin never tuned up a car before...Im just p*ssed...I put all this money in it and it still isnt RIGHT!!!!

 

Call Corvettes West and talk to Tommy Moller.
6175 Clark Center Rd. / Sarasota

922-2300

Known him since 1975. Knows what he's doing and he's trustworthy.
Tell him Russ sent you.

 

So when you took it to Goodyear, and they hooked it up to the computer and didn't see any error codes

You need to try to fix it yourself, get a vacuum gauge and dialback timing light, like BarryK said.

You will feel more confident going for a ride if you know you can fix things yourself. You can do it. Save money too.

 

So what is feeding your choke hot air? Are the carter's suppose to have a choke tube to the exhaust manifold?

Mark

 

Install a manual choke, if that's your problem.

You said you usually idles around 1800 2000 rpms when cold, that's a bit high, 800 + or - 50 would be better. Is that how you got it back from the mechanic you took it too.

Formula Outlaw Has your answer:


Call Corvettes West and talk to Tommy Moller.
6175 Clark Center Rd. / Sarasota

922-2300

Known him since 1975. Knows what he's doing and he's trustworthy.
Tell him Russ sent you.

 

That's when you start buying book after book and dvds etc etc so that you can learn as much as possible. Then you buy tools and tool and tools and start practicing.

 

before you go rebuilding the carb check your dwell on your points.if it is off it will cause alot of the symptons you have. make sure you set the dwell before you set the timing. changing the dwell will change the timing. also you need to plug the vaccum advance line. if the dwell does not stay in specs it may be a worn dist shaft or bearings. hope this helps. go for the simple stuff first before tearing it apart.

 

So, it sometimes runs good. For a few seconds, for a few minutes?

You just drive along, nothing changes like you step on the gas,a nd it starts running OK?, or it starts running OK when you change something like throttle position?

If it runs OK sometimes, it is nothing major like a slipped timing chain.

Just because a carb was rebuilt, doesn't necessarily make it any good, as you may still have a blocked circuit, or internal gas leak. I am about as fond of carbs as I am points.

Doug

 

Believe me, I've been there...........felt the frustration. Decided it was time to learn it myself or sell the car. I wanted to keep the car so I started to learn.

Is your timing light a dialback model? if not, splurge and go to sears and get one, they are about $69 which is usually less than a single hour of labor mechanics typically charge to work on your car and NOT fix it so it will pay for itself the very first time you use it. Take my word on this! The vacuum gauge will run you about another $20-$30. $100 invested will probably last you a lifetime. OH! almost forgot, while you are at Sears getting those two tools, pick up an inexpensive dwell meter. Many (all??) have a built in tach meter too so you can see your rpm's while setting dwell and to set idle on the carb.

next, go to my website and download and read two EXCELLENT tech articles by John Hinckley (JohnZ here on the forum). Honestly, reading those two papers is what got me started doing my own timing. The one paper will explain about timing, what it is, what it does and why it's important to get right.
The second paper will basically take you step by step through setting the timing on your car.

If a complete idiot like me can read John's papers and do it than anyone with brain activity enough to still be breathing can do it. Trust me on this - I had never used a timing light before and previous to doing it myself the only work I had ever done on a car was a month or two prior I had to change out my fan clutch and I needed help with that and that was only four bolts!
that's how new I was at working on cars and how well written John's papers are and easy to understand and follow.

My website tech articles page is here:
http://69.253.166.197/page1/page65/page65.html

the two articles you want are:
Timing101Article.pdf
MAPPING ADVANCE.pdf

if you right click on the name of the files you can download them to your own computer to read when you need or to print out.

Basically what you are going to do is set your dwell on the distributor and get your timing set. Than you will check and adjust the fuel/air mixture and idle on your carb, than I usually go back after I adjust the carb mixture and idle and recheck the timing just to be sure nothing changed.

Even your very first time doing it shouldn't take you more than an hour or so and after you have done it a few times you will be able to check & adjust dwell, check and adjust timing, and check and adjust carb mixture in about 10-15 minutes. Best of all you will knowit's correct and it didn't cast you a bundle to pay a mechanic to do it (and still have it be wrong)


** Russ's idea of taking it to Corvettes West is very good and I'm sure they can get you running correctly but why pay them? Do it yourself and you will save money and best of all feel good knowing you did it yourself. Save them for when it's something very major you don't have the tools for such as changing out bearings.

 

oh yes Doug, we know how much you LOVE points..........

 

Yup.


Glad to hear the non-resistor plugs fixed your problem. I think I may have had to run those to make the car run OK when I was still in the stone age, but that was over 30 years ago.

As the non-resistor plugs became harder to find (especially for the small plug heads I now have), I switched to resistors and never had any problems with high RPM breakup.

Doug

 

BLK63Vette, I'm going to blame the carb, BUT it is very fixable. From what you describe, the car is running rich due to either improperly set floats or a missing "brass pintle" located in a circular hole under the primary squirters towards the front of the carb. The Carter AFB carb is fairly simple and a VERY reliable carb if rebuilt properly. Sounds like someone didn't know what they were doing.

Whenever I get a carb from someone, I always dissassemble the body to see if the floats were damaged in shipment. 99% of the time things are OK, but that 1% will come back to bite you.

There is a great book on Carter carbs by Dave Emanuel that you can buy on ebay if you type in Carter AFB Carb and do a global search. BUY ONE!!!! The ISBN No. is 0-931472-11-3, Part No. 11. It will be the best money you spend. Again, the Carter AFB is not complicated and you can work on it with nothing more than a screwdriver, a pair of needle nose pliers, a crescent wrench and some aerosol carb cleaner. The key is remembering where everything fits. Buy a digital camera, buy the book, and buy a six-pack of your favorite spirits. Good luck!!

 

Pete,

You haven't seen your ex-girlfriend messing around with your car have you?
I'm sure some of the Forum gurus will point you in the right direction. In the meantime, it is frustrating when something goes wrong with our toys. Keep in mind that they are pretty basic cars and fairly easy to fix. Hang in there.

 

One nice thing about Corvettes West, is that at least on Midyears, Tommy will allow you to watch the mechanic to learn how to do this stuff. Not many shops will do that anymore....

I've spent entire days at the shop watching them and learning. I still feel stupid at times although I did fix my headlight not revolving issue last night WITHOUT staying at a Holiday Inn Express....