Stripped Carb

[chevyaddict]

Well folks... I couldn't be more upset with myself. During a routine filter change I very badly stripped out the carb body where the filter housing threads into the carb on the 81. I don't think its rethreadable although I will try that with a machine shop.

Of course a replacement carb is outrageously expensive and for someone out of work, like myself, its a PITA. So my question is, if I do a holley replacement, how much is that going to affect my emissions and vacuum systems? How integral is it to make sure all that stuff is hooked up? In AZ they open the hood to check things but they don't take the air filter off so they wouldn't see lines not hooked up but I'm assuming that all those vacuum lines are needed to be fed to keep the rudimentary computer happy. Any advice would be surely appreciated........

 

[BigJimZ16]

Other options...

Have you considered the possibility of locating a previously used carb in any condition as a donor for the top section that has the filter housing in it? The parts swap would be simple, also a good opportuity to check the float, needle and seat!!
Just a thought...

Almost forgot... repair at a machine shop is not a good idea because of the pot metal casting. It doesn't take new threads very well. Also, some material (Belzona) would need to be added to replace the lost threads.

 

[chevyaddict]

Have you considered the possibility of locating a previously used carb in any condition as a donor for the top section that has the filter housing in it? The parts swap would be simple, also a good opportuity to check the float, needle and seat!!
Just a thought...

Almost forgot... repair at a machine shop is not a good idea because of the pot metal casting. It doesn't take new threads very well. Also, some material (Belzona) would need to be added to replace the lost threads.

That is a great thought actually - I will certainly try that option.

I can also see now that I have it off that (and silly me I should have realized this) I can't just put an aftermarket holley on it unless I swap the manifold or put an adapter on it which I wouldn't do. Thanks for that info on the machine shop. I'm going to try to get it to thread off the car but the threads are pretty toast. GRRRRR........

 

[BigJimZ16]

As a former "Guardian Maintenance Mechanic" at a Chevy Shop back in NJ, I can tell you that MANY a fuel filter fitting was either cross-threaded or outright stripped by persons who knew better in the late 70s. NAPA used to sell an inlet repair kit that was nothing more than a self-tapping fitting that was a half size larger. Sometimes they even worked!

 

[chevyaddict]

As a former "Guardian Maintenance Mechanic" at a Chevy Shop back in NJ, I can tell you that MANY a fuel filter fitting was either cross-threaded or outright stripped by persons who knew better in the late 70s. NAPA used to sell an inlet repair kit that was nothing more than a self-tapping fitting that was a half size larger. Sometimes they even worked!

Well, unfortunately how you described does not fit my carb. Its the main body of the carb that this is a part of - not the top section. I tried to rethread it back in as best I could and reput it on the car - leaking like a siv. The threads are so badly messedup now there isn't anything I can do with it.... looks like I'm buying a new carb.

 

[petes74ttop]

Don't Panic!

Stripped filter inlets are common, you can fix it by inserting a "Heli-Coil". It's a cheep and effective repair. PG.

 

[chevyaddict]

Stripped filter inlets are common, you can fix it by inserting a "Heli-Coil". It's a cheep and effective repair. PG.

Where do they sell them that large? I think my problem is its not allowing the piece to ceat (sp?) against the back of the inlet and its profusely leaking even though I got it most of the way in. If they sell something I'd rather go that route... this carb is working perfectly!

Back to how large... that is a monster hole and its also under pressure with the fuel. How would I ensure there wouldn't be leaks? Either way I didn't think they sold drill bits that large so how would I drill out the area to even install the helicoil? Anyone done this before on a carb... have you Pete????

 

[petes74ttop]

Hi again, no I have not needed this repair yet. You can try a self-tapping fuel filter inlet or try a machine shop, I think the size is 7/8 20.
Here's a shop that will do it for you but you have to take the carb apart first Carburetor Bushings PG.

 

[G Winter]

Is that carb computer controlled ? If not there has to be a lot of QJ carbs in the salvage yrds that you could get a matching body from.The main diff on them is the cfm rating. I think the 454s were larger other than that I think most were the same.
You just have to campare vacuum fittings , you may even be able to drill some of the missing holes for the fittings.
good luck.

Glenn

 

[TimAT]

There used to be a couple of repair schemes- one, as BigJim pointed out, is a self tapping fitting. THe other is a fitting that is expanable and has 2 o-rings. as you tighten it up (2 wrenches) it expands the o-rings and seals. The problem with either one is that they get installed without a fuel filter and removing them makes it really dead. YOu do need to install an in-line filter of some type.

Unless you're concerned with keeping the numbers matching, The best bet is to get a donor q-jet from a salvage yard or fleabay, and swap the parts from yours to the donor main body.

And just to state the obvious- you are NOT the first one this has happened to.

 

[chevyaddict]

Thanks for the advice guys but I am just not comfortable going to a salvage yard to get a used carb.... soft metal tends to warp when its not kept in a fashion that keeps it true. I've experienced too many warped carbs in my time. I was thinking about the O-ring thing and don't have a problem with an in-line filter..... its just now the threads are so bad I'm not sure I can get anything to tighten down sufficiently STRAIGHT at this point. No matter how much I try it goes in crooked and that is why its leaking. Even with an o-ring I'd have that trouble because it wouldn't ceat properly. I guess it can't hurt to try it before I spend the $430 bucks. Thanks for all your help!

 

[Vette79]

This guy was able to help me and fine69. We both bought carbs from him. He will be able to help you out and answer your questions more specifically as well as provide parts and idea's. It couldn't hurt to call...

eBay Store - mtnmancarburetorandfuelinjection: ROCHESTER CARBURETOR PARTS, ROCHESTER QUADRAJET CARBURETOR, REBUILD GASKET KIT

 

[chevyaddict]

This guy was able to help me and fine69. We both bought carbs from him. He will be able to help you out and answer your questions more specifically as well as provide parts and idea's. It couldn't hurt to call...

eBay Store - mtnmancarburetorandfuelinjection: ROCHESTER CARBURETOR PARTS, ROCHESTER QUADRAJET CARBURETOR, REBUILD GASKET KIT

THANKS!!!

 

[chevyaddict]

I'M THE WOMAN

Well, I decided to go up to the hardware store and see what type of o-rings I could find that might fit in there sufficient enough to take up the extra space from the fitting going in crooked.... "what the heck" I thought.... might as well try it and low and behold... IT WORKED!!! So I added an external fuel filter and that was THAT!!! Woo Hoo!!!