Straightening Holley carb parts - Clem Zahrobsky??

[Bob S.]

Greetings -

Has anyone who has straightened Holley carb parts used heat to facilitate the process? Clem, I recall you posting a picture of a fixture you've used to straighten Holley metering blocks.....??

If heating has been successfully used, what temperature?

I'm faced with a 3810 main body whose metering block surfaces are significantly "warped". The throttle plate mounting surface looks pretty flat. The distortion is near the bowl attachment holes. I fear that simply machining those areas to make the surfaces flat would weaken them and make future warping likely....

Regards,
Bob S.

[John M.]

Re: Straightening Holley carb parts - Clem Zahrobsky??

Bob,
I did this by milling the surface flat while holding it in a fixture that I made. It's flat and seems to work ok with no apparent weakness. It's the primary side on a 3310 Holley if that helps.
John McRae 30025

[Gerard F.]

Re: Straightening Holley carb parts - Clem Zahrobsky??

Bob,

My 3810 body was warped especially at the metering surfaces. So I had all three surfaces milled flat at a local machine shop. Cost about $50.




No problem with the body weakening.

But then I had to straighten the metering plate flat in a vise between two plates (or in a fixture similar to Clem's). Luckily, my metering block was flat, or I would have tried to bend it also.

I think heat would probably do more damage to cast potmetal parts than the milling.

[Timothy B.]

Re: Straightening Holley carb parts - Clem Zahrobsky??

Bob,

I also took my holley to the machine shop to have the surface milled but I am still having problems. I had a back fire and think power valve is blown. Ever since I plugged the hot slot holes in the iron manifold the car takes a long time to warm up and carburetor seems richer than I remember when holes were open. Seems like it ran better when the slot was open.

I know this sounds strange but my 3810 seems to be jetted rich at idle as the car runs best with air emulsion screws 3/4 turn out and no transfer slot exposed. I have not had time to play with it lately, it's not sleeping at my garage.

How can a carburetor be so simple and so much trouble..

Check out this heat shield.. no doubt it needed to be replaced but I wonder if the car would run differently with the slot exposed and new gaskets.

[Michael W.]

Re: Straightening Holley carb parts - Clem Zahrobsky??

Clem is not presently a member so cannot respond to posts.

[David D.]

Re: Straightening Holley carb parts - Clem Zahrobsky??

I am by no means an expert, but, over on another forum, when this conversation came up, the replies were....

"With a proper fixture these metering bodies can be pressed straight as i have been doing that for years. NEVER machine them flat as you will remove all the protrusions that "bite" into the gasket to help it seal."

Any truth to this? Or is machining flat an acceptable procedure?

Thanks,
David

[John M.]

Re: Straightening Holley carb parts - Clem Zahrobsky??

David, The surfaces that we are talking about are flat or meant to be. The protrusions are on the mating parts, the fuel bowl and the metering blocks.
I my case milling the body was the cure. I think that Jerry would say the same.
John McRae 30025

[Gerard F.]

Re: Straightening Holley carb parts - Clem Zahrobsky??

Tim, Bob,

Check to see that all of your Idle and High speed vents are open and clear to a passage to the meeting surface. Also that there is a corresponding vent hole in the metering block.



In the picture above of my 3810, one high speed vent on each side was left undrilled. (You can see it in the picture). I also had the corresponding place in the metering block left undrilled.

I wound up drilling these vents out with a corresponding numbered drill size of the vent that was open. Also drilled out the metering block.
Check them by blowing air through the body if you have the body carb off the car.

Tim, if any of these vents are blocked, you will tend to siphon gas in the air horn and run rich.

Also, the advantages of blocking the heat slot are for the summer running to keep your carburetor from cooking. In the winter and in cold climates, they all run cold initially, and I guess they would warm up slightly faster with the heat slot unplugged, but I don't see the advantage if you do a lot of cruising at high speed.

Also Bob, use those blue resilient gaskets, thay are very forgiving (even though you might take a point or two at judging)

[Dick W.]

Re: Straightening Holley carb parts - Clem Zahrobsky??

Back up here in the red neck hill country we just use a pane of glass laid flat on a work bench. We tape a sheet of 600 grit sandpaper to the glass. Using an orbiting motion, we slowly move the offending body or base plate over the sandpaper. Continue this until all the surface is shiny. In over 40 years of doing this have never had any problems.

[Gerard F.]

Re: Straightening Holley carb parts - Clem Zahrobsky??

More info here:

https://www.forums.ncrs.org/showthre...vents&uid=5056

[Joel F.]

Re: Straightening Holley carb parts - Clem Zahrobsky??

Clem is not presently a member so cannot respond to posts.

Is it possible to have "honorary members" for posting purposes? Members who pay no dues, receive no printed publications, and are conferred none of the benefits of membership other than being allowed to use this board?

I ask because Clem has been a strong contributor to this and other internet Corvette boards for many many years, and it is a shame to lose a lifetime of high performance engine building knowledge over the matter of dues.

[Terry M.]

Re: Straightening Holley carb parts - Clem Zahrobsky??

There is only one type of membership in NCRS, and I doubt anyone wants to take on the complications of different types of membership any time soon.
A little bird just told me Clem is back in the fold. Have some patience for him to get back with us.

[Michael W.]

Re: Straightening Holley carb parts - Clem Zahrobsky??

Glad to hear that his sugar daddy came through

[Bob S.]

Re: Straightening Holley carb parts - Clem Zahrobsky??

Back up here in the red neck hill country we just use a pane of glass laid flat on a work bench. We tape a sheet of 600 grit sandpaper to the glass. Using an orbiting motion, we slowly move the offending body or base plate over the sandpaper. Continue this until all the surface is shiny. In over 40 years of doing this have never had any problems.

Yep, that's just what I'm doing. Just finishing up the first surface now....

And yes, I'm in red neck hill country too!

Bob

[Dick W.]

Re: Straightening Holley carb parts - Clem Zahrobsky??

Forgot to add one thang.....THROW AWAY THE BIG SCREW DRIVERS!!!