• When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

Rebuilding carburetors at home

Kern Dog

Life is full of turns. Build your car to handle.
FBBO Gold Member
Local time
6:15 PM
Joined
Apr 13, 2012
Messages
35,612
Reaction score
125,485
Location
Granite Bay CA
It has been awhile since I did a full rebuild on a carburetor. I’ve changed jets, power valves, metering blocks, accelerometer pump cams and such but it has been years since I did a full tear down.
I have these cars out back:

0188.JPG



IMG_1212.JPG


They both have mild 360s with the most basic of all Holley carburetors, the 600 4 barrel manual choke, list 1850.
Sort of like this one:

Holley 1B.jpg


I bought these rebuild kits:

1704505954722.png


Since it has been awhile, are there any tips or short cuts anyone has to offer?
I'm going to get a can of that Chemtool carb solvent to dunk the parts into and I have a few cans of carb cleaner.
I thought maybe I've missed out on some tips since the last time I did this.
 
Make absolutely sure everything is clean. Match up new and old gaskets to make sure the holes are identical.
Doug
 
Make notes as to where everything goes. Pictures help. Keep the primary parts separate of the secondary parts.Watch the gaskets closely as some kits have several different ones. Clean all the passages well. Its not rocket science.
 
One carburetor I had on the Duster developed a blocked internal passage for the accelerator pump. The ethanol here is okay if you run the engine on a regular basis but fuel sitting inside awhile seems to lead to crud buildup.
How do you adequately clean a small passage? Nobody makes "pipe cleaners" that small.
 
Don't dunk the float bowls in the cleaner. There are o rings behind these metal plugs that are crimped into place and not easily replaced.

100EF082-B25E-422D-A112-58E3D198F287.jpeg
 
I've always used what I call "tag wire" to poke out and clear real small passages. Have you ever seen tags made of manilla folder material with a wire thru the hole for marking your water shut off valves and other things in your basement ?
 
Soaking the metering blocks and main body should dissolve passage crud with a long enough submersion. The EPA made these carb cleaning solutions very weak compared the "good old stuff" so, longer soak time is something I do. You may want to rinse with hot water and use compressed air to blow out every passage. Excessive corrosion sometimes cannot be removed so, that piece will be scrap. Use the supplied instructions, adjust in the order of the instructions-important! Years ago, I averaged 1 carb or more per week. Now if I do 3 a year, I'm surprised.
Mike
 
Dosens Carburetor Carb Cleaner...
amazon.com/dp/B076LJSY3P?ref=ppx_pop_mob_ap_share
 
I use brake cleaner (the good stuff, not the enviro-friendly crap), being careful of splashback into eyes
of course!
It does a better job of "instant" crud dissolving than carb cleaner does, at least in my experience - and
using it with the straw opens passages nicely, to be followed up with something small and flexible enough
to get through there after.
Another nice benefit of Brakleen is it dries almost instantly, too. No residue.
 
One carburetor I had on the Duster developed a blocked internal passage for the accelerator pump. The ethanol here is okay if you run the engine on a regular basis but fuel sitting inside awhile seems to lead to crud buildup.
How do you adequately clean a small passage? Nobody makes "pipe cleaners" that small.
If you go to your local weld supply, they sell something called a “cutting tip cleaner”. It’s about 5-6 bucks and good for cleaning small orifices. For harder to reach areas, electric guitar strings should work. A pack should be about 5-6 bucks too, and they’re usually about 2 1/2 feet long. Also, there’s a guy on YouTube, whose name is escaping me right now(Uncle Tom? Cousin Larry? Grandpa Joe?) that says he uses a single strand of bristle removed from a stainless steel brush with a needle nose. Brush can also be found at weld supply shops.
 
If you go to your local weld supply, they sell something called a “cutting tip cleaner”. It’s about 5-6 bucks and good for cleaning small orifices. For harder to reach areas, electric guitar strings should work. A pack should be about 5-6 bucks too, and they’re usually about 2 1/2 feet long. Also, there’s a guy on YouTube, whose name is escaping me right now(Uncle Tom? Cousin Larry? Grandpa Joe?) that says he uses a single strand of bristle removed from a stainless steel brush with a needle nose. Brush can also be found at weld supply shops.
I use them too, but be gentle with tip cleaners, they are files
 
Air brush tip cleaners, HF has them cheap enough to toss if you ruin them.
 
I sure don't want something that will flake off and leave strands in the passages.
 
I recently bought an ultrasonic cleaner and ran an old AVS through it. I took it off my 67 about 20 years ago and it ran fine. It came out looking clean but I wasn't amazed until
I drained my machine. There was probably a solid 1/8” of seediment on the bottom from cleaning it. I wish I had taken a picture before most of it flushed out the drain as what’s in the picture below is just a fraction of the sediment. It doesn’t do anything for rust on linkage - I used some Naval Jelly for that and the stains in the bottom of the fuel bowls did not lighten up.

IMG_1079.jpeg
IMG_1083.jpeg
IMG_1827.jpeg
IMG_1831.jpeg
IMG_1121.jpeg
IMG_1127.jpeg
 
It has been awhile since I did a full rebuild on a carburetor. I’ve changed jets, power valves, metering blocks, accelerometer pump cams and such but it has been years since I did a full tear down.
I have these cars out back:

View attachment 1585747


View attachment 1585749

They both have mild 360s with the most basic of all Holley carburetors, the 600 4 barrel manual choke, list 1850.
Sort of like this one:

View attachment 1585755

I bought these rebuild kits:

View attachment 1585746

Since it has been awhile, are there any tips or short cuts anyone has to offer?
I'm going to get a can of that Chemtool carb solvent to dunk the parts into and I have a few cans of carb cleaner.
I thought maybe I've missed out on some tips since the last time I did this.
As others have said, obviously clean, clean, clean.

One of the problems with Holleys are that that they warp. Then you can rebuild them all you want and they don't work worth s**t.

Once you get the main body separated check it for straightness. I'll almost bet that the body, behind the metering blocks, is warped (this is because people tighten the heck out of the fuel bowl screws). If it is warped, file or sand it until it's flat. Check also where the body connects to the throttle plate, although this area is much less problematic.

Here are a couple of pictures to explain what I mean.

This is near the beginning of filing. Note the dark areas that have not been touched, and conversely, the edges that are high and therefore have been filed.
Screenshot_20240106_084110_Gallery.jpg


Here is another carb near completion. You can still see low spots.
Screenshot_20240106_084022_Gallery.jpg


Bottom line is be sure the body is flat! If it is not, then you may end up with internal leaks that will make the carb impossible to tune!
 
I wasted my money on one of those “trick kits” when rebuilding my 6bbl setup. It had enough parts to do about 1 1/3 carbs, the rest was generic junk I didn’t need. So I called Holley directly, and the guy put me together just the stuff I needed. My advise would be to do the same.

I also separated each carb to its own tray, and did one carb at a time. Cleanliness as mentioned above is paramount.
 
Auto Transport Service
Back
Top