comp

whats the best repair ?????

GDaina

take it to a carb repair place, may cost you around 50 bucks, they will insert new threads..if you attempt to do it yourself, you need the kit... prolly costs around 150-175....

comp

ouch,,, no Heli-coil kit's

lars

I have all the tooling to repair the early model 7/8-20 inlet threads if you need it done (not the 1"-20 later model). For info, drop me an e-mail request to
V8FastCars@msn.com

The only way to repair it is to machine it, tap it, and install the stainless steel thread insert, and it's a non-standard size not made by HeliCoil. Don't use the self-tapping plugs or the O-Ring inserts - they are only temporary fixes that will soon leak.

If you've stripped out a late-model 1"-20, I can put you in touch with a guy who has the tooling to do that work.

GDaina

Either that or a new one, the self threading nuts don't work.

You can try the nut, and you may luck out, but they leak and if the threads are gone, there is not enough metal for the nut to grab and be effective

comp

it's the 1 inch J-B Weld ,tap and use Loctite stud & bearing mount.. then and filter inline

lars

2 problems with that:
1. JB Weld won't hold
2. 1"-20 is a non-standard thread size, so you won't find a tap

If you want it done right with the 1"-20 threads, you can disassemble the carb and send just the float bowl out to "Mr. Carburetor" in Cleveland. Call and talk to John (owner) and tell him you talked to Lars in Denver - he's a good guy. His number is 440-779-7917.

Lars

comp

man , my luck carb is for a 77 P/U

kens 80

Pick up a used carb and get it rebuilt. Most Q jets (used)are cheap.

comp

i have 8 but i was allmost done "deburing" it when i noticed

GDaina

yup, John is the guy, been to his place numerous times. Last time I was there, he charged 50, don't know if his price is the same or higher now.

Acually he's in North Olmsted, western suburb.

Tom454

I used to work at an autoparts store and we sold Delco Rochester parts... we had 4 different sizes for the Q-Jet-
Standard
Single Oversize
Double Oversize
Triple Oversize

I agree with Lars that the JB Weld is a bad idea.

And... the oversize repair fittings are pretty much a "Bubba", although I have had good results on occasion with them. Cost/expediency becomes a factor with family sedan owners and milk trucks.

I did sell a lot of them, and installed my share.

NAPA also has the OS repair kit, FYI.

I found on some Q-Jet applications the oversize repair caused the fuel line to go out of alignment because of the added thickness of the repair fitting. This caused its own set of problems with steel lines not threading & sealing properly.

These guys have the thread insert kit.... yowser... $$$$
STK1-20 1-20 Carburetor Kit STK1-20 $323.75
http://www.newmantools.com/price/stkpr04.htm

Another one: (no price)
http://www.aboveboardelectronics.com...chapter_10.pdf

The correct repair is the thread insert.. This ends up being stronger than the original cast threads.

I have an enormous set of helicoils & taps/dies having owned a machine shop.... but I never had that set. Not enough money in it to bother.

comp

^THANKS i don't mind some riggin' just no leakin'

lars

My experience with the over-sized self-tapping inserts is the same as Tom's. What I have found is that the rotted-out, corroded, stripped old threads are not conducive to holding the self-tapping inserts for very long, and the first time any force is placed on the mating fuel line (to attach it or disconnect it), the insert strips back out again.

The stainless steel thread repairs using a HeliCoil-style insert (these Q-Jet inserts are not made by HeliCoil) are very good, and produce a permanent repair. By using the correct tap for the insert, which cuts a deep, good quality set of threads for the insert, the insert can be permenantly installed. But this tooling is expensive. I have bought all the tooling to do the early Q-Jets (up through about 1973) using the smaller 7/8-20 inlet thread (black gasket on the inlet nut with the gasket up against the hex portion of the nut), since the early carbs are the ones usually seeing this type of inlet failure. It's actually uncommon for the 1"-20 inlets to strip out, so, like Tom, I have not forked over the $$ for the tooling for those.

lars

Yup, John and I both charge $50 for the inlet repair if we are just given the float bowl for repair. We both use the same style fixturing, and we both get our tooling and inserts from the same place. Difference is that John has spent the money for both insert sizes, and I only have the small one...

...and if anybody comments on that, I'll have your Vette towed away.

Philvet

M S C Has a 1''-20 tap, $73.71, Phone 800-645-7270

Tom454

Yeh... McMaster has one too ($54). I had a brain fart and thought it was a good idea too... but you don't need a 1-20 tap to fix those threads. They are shot. The tap will only clean up the shot threads.... which will get you no where. You need to bore it oversize, tap it with a special tap for the thread insert, and wind in the insert. Plus.... since it is a limited depth thread, it is essentially a "blind hole" and the tap has to be a "bottoming" style tap, not a barrel tap, which is the common design. McMaster has the 1-20 bottoming tap in both a 4 flute design and a 6 flute design. But.... we don't need no tap.

The kit I referenced above will have the correct drill, tap and insert.

Plus... the point Lars made about the fitting coming lose the first time it's wrenched by the "ape tool", it usually lets loose. That's been my experience as well.

UKPaul

Hi Lars Do you know the turnaround time for John to sort a 1"-20 thread?
There are Helicoil type kits available for both the 7/8" & 1" inlets that are made by an Australian company Fairchild Fasteners (sales@recoilusa.com). They're called Recoil & there's repair kits listed under "Special Thread Size: Carburettor". I've got several Recoil kits (which are good value for maney) so thought that getting one to repair my carb wouldn't be a problem. It wasn't, but the price was. I was quoted approximately £180 ($330) plus VAT (tax). I didn't bother! I think the price was ramped up by the local shop as they can't be bothered to order one offs (had the same happen when I tried to order a reamer pilot), so the kits could be a lot cheaper than I was quoted.

GDaina

John is in my hometown, I can make a call for you and find out if you're interested.

Tom454

[QUOTE=UKPaul

There are Helicoil type kits available for both the 7/8" & 1" inlets that are made by an Australian company Fairchild Fasteners (sales@recoilusa.com). They're called Recoil & there's repair kits listed under "Special Thread Size: Carburettor". I've got several Recoil kits (which are good value for maney) so thought that getting one to repair my carb wouldn't be a problem. It wasn't, but the price was. I was quoted approximately £180 ($330) plus VAT (tax).

[/QUOTE]

That's the kit sold by the company in the link I posted above.... you can see pics at that site, but it is a pdf link so dial up beware.

http://www.aboveboardelectronics.co.../chapter_10.pdf