Car won't run and I've nailed it down to the carburetor. When I pump the accelerator there are only a few dribbles not a strong stream as I've seen in the past. If I manually squirt fuel in the carb, fires right up, otherwise nothing. The car was running and driving fine last week, but stumbled and few times then quit. Seems like it was starving for fuel. While waiting for the flatbed I pulled the fuel filter. It was packed with debris. blew it out the best I could and put it back. I then scavenger a hose a checked the fuel pump. It was working but seemed no where near the 1/2 pint every 30 seconds I read about. So this week I installed a new few pump, fuel filter and removed the gas tank for a thorough cleaning. Tank is spotless inside. I blew out the lines and changed all the rubber hoses. Now I easily get a quart plus per minute while cranking.

Is there anything I can do to get this carb functioning w/o missing the rest of the summer buy sending it away for a rebuild and attempting to rebuild myself?

Background - This 1978 L48 is a survivor that I literally pulled out of barn 2 months ago. It only had 20K original miles but sat for 25 years. I spent the past 2 months replacing everything needed. Several on this forum suggested I rebuild the carb (send it to Lars) but I didn't do that because it ran so well and I didn't want to wait.

 

You need a complete carb rebuild and proper setup. Your accelerator pump is shot, and your secondary airvalve spring is way out of adjustment, allowing your airvalves to hang wide open. From the looks of it, and the fact that your airvalves are that far out of whack, I'm guessing every other aspect of the carb also needs attention and setup. No, you cannot get that carb running right without rebuilding it and installing new internal parts. Carb looks like a very nice, unmolested original carb, so whatever you do, don't let some "mechanic" talk you into trading it in for a "rebuilt" carb. That would be a very bad mistake...

Lars

 

Be SMART send your carb to Lars, unless you are feeling lucky and have vast experience and known rebuilding carburetors. Many Forum Members have the expertise to rebuild their Quadrajet, but most people don’t, like me. I am old and life has taught me a few lessons, I am happy to fix things and love to work with my hands doing all types of projects and repairs. That being said, the time, money, and unhappiness can be avoid by sending your carb to Lars. He rebuilds your carb, then tests it on a real engine. My son has convinced me to always read Customer Reviews before making a purchase, and I can tell you that all the guys who let Lars rebuild their carburetors are more than pleased. You could do like my friend, who is a professional trained repair tech and extremely skilled, then end up with a boat load of problems. He has removed/reinstalled his Quad so many times that the inlet line from the fuel pump started leaking. He always has trouble trying to start his car after the engine gets hot, and I won’t tell you all the parts he has bought attempting to fix the problem.

 

Clint said it best, a man has to know his limitations.... and maybe Do You Feel Lucky.... Do you have carb experience or good mechanical aptitude? If so I'd give it a look and a try...Here is why...

Your problem seems to be rather sudden which for me limits things being just out of adjustment, you have no fuel to the idle circuit and very little to the accelerator pump. Could be the pump is bad and I'd replace it anyways but that does not explain no Idle or low speed, once you dump fuel in and it runs that circuit should pick up. Since you had crud in the system I assume it got into the carb and a good place to start is from the inlet on in... Idle tubes like to get clogged... I have an Ultrasonic cleaner I use for fire arms and fishing reels, it also works great on carbs and varnish build ups, does not get chunks though...

I say live a little and learn a little, get a good kit and take a look at it, the worst that can happen if you use good judgement is that you will have to throw money at it later... I have not heard one bad thing about Lars or his work so that is certainly another option...

60

 

Are you available to rebuild this for me? If yes please let me know details and I'll get it shipped out asap.

I'm an automotive engineer in Detroit but know nothing about carburetors. I'm trying to keep this car all original so prefer not screwing it up with a learning experience. Thanks for the reply...LMK

 

You need to write to Lars directly at v8fastcars@msn.com.

He will send you email explaining what he will do..

Had my 78 rebuilt by Lars a couple of years ago

 

Smart decision! You can now start working on other issues that you Corvette may have. One thing with our cars is they are extremely NEEDY Girls. Mine is almost 50 and every month or so, I am fixing something, Chevrolet never intended these cars to last so long. What a wonderful Hobby?

 

My husband can attest to Lars pretty damn fast turn around time including shipping both directions, I believe it was just at a week & 1/2 and he needed to find a couple of small parts
Hubby says carb looks nice, old parts were returned back to us to see how bad they were.
Haven't run carb yet, still working on a complete new fuel system retro fit from filler cap & tank to the inverted flare adaptor to AN fitting.
Hubby had to fix Tanks Inc. poorly engineered EFI tank pump assemble all nice and clean setup with lines running straight towards the rear
of car now, on to plumbing & electrical now

a couple of things to note if sending to Lars
1) BOX SIZE REQUIREMENTS,
2) remove baffle & air filter stud between primary & secondaries = shame on my husband
3) packaging, packaging, packaging

 

Information forwarded to you.

Lars

 

Tim -
I've offered this before to various Forum members (since some like to do it and others don't want the publicity), but if you'd like I can do a little "documentary" post about your carb and the rebuild process for all to see. Your carb appears to be a good, solid, original carb in releatively unmolested condition, so it may be a good candidate for a good example of a more "normal" carb rebuild and setup. In the past, I've covered a lot of rebuilds of carbs that are seriously screwed up with some very odd problems. Many of the readers here might like to see what a more "normal" carb should look like, and the process to do a basic setup for some good performance in a stock application.

We can do a quick polling for interest level: Would you guys like to see what Tim's carb looks like inside and what it needs for a nice setup..?


Lars

 

100% absolutely yes. Please and thank you. I'm jumping out on a limb here thinking the response will be unanimous.

 

I'm always interested in the process threads and you never know what you'll learn from them.

 

I would love to see the process of rebuilding this carb. I’ve rebuilt two QJets, both with parts from Cliff, one for my ‘71 Corvette and the other for my ‘72 Pontiac LeMans 400. It would be great to see how close I got to getting it right.

 

Yes please

 

There are only a few carb guys out there that I have found to trust what advise they give on Quadrajets.
Every response givin to a certain issue with these has provided something new to learn.
Complete write ups like you(Lars) have done in the past has always given something even more.
I'm in. Sign me up.

 

I hope op says yes!!!!
always appreciate thetime and effort to post and document and share.
i want to see that accelerator pump and other sitting parts.
i think i reread all rebuilds posted several times.
fyi my still running perfect rebuild! Similiar miles..

https://www.corvetteforum.com/forums...l82-q-jet.html

 

Looks like we don't have anyone suggesting that they would rather see photos of my large, hairy man-***** than photos of another Q-Jet rebuild, so Q-Jet rebuild photos it is. I'll verify that Tim is OK with me posting his carb info - haven't heard from him on this subject yet.

Now, of course, if you guys would like some Lars swimsuit calendar photos interspersed with the carb rebuild, I can accommodate that as well, just to make sure all interest levels are included.

Lars

 

We have a "GO" from Tim to do the technical photo essay, so look forward to some fun with the teardown, inspection, rebuild and testing!

Lars

 

Well hold on now! We didn't know your large, hairy man-***** were on the table as an alternative. (That's quite the visual pun there.)

The swimsuit calendar idea is a good one; maybe a CF C3 superstar calendar with 12 of the most popular contributors! Let's see... Lars is Mr. January (since it was your idea), then we have Jebby, AllC3forMe, Interpon, Rescue Rogers, 4-Vettes, Priya, Mooser, GTR1999...