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Was thinking about putting a re-build kit into my one bbl rochester in my 67 C-10 250...
not sure if I would get in over my head...

anybody care to throw me a few tips on it inc what a standard 're-build kit' includes/involves

the truck runs pretty good but I can see a little leaking around the gasket in the middle of the carb and I am thinking I may be losing some vacuum over it and maybe messing with the mix...not to mention what kind of years of gunk may be in it..

TIA

Florida,

If you can chew gum and walk at the same time you should have no problem with the rebuild. The leaks between the two pieces is a notorious problem on Rochesters...the fix is suppose to be a heat/cool cycle while fixtured to a rigid plate. This is a procedure performed by professionals.

Everything is included in the kit. The only item that could be a problem would be the proper "soaking" medium. Berryman makes a neat 1 gallon carb cleaning can, complete with little basket.

The cleaner is caustic and VERY smelly. Gloves would be mandatory, and it would be wise to use it in the far corner of the back yard!

Compressed air would be needed to blow out passages and dry the parts after washing with a hose.

To end this novel..yes, it's easy if you follow the directions. You need the cleaner and a small compressor, or some source of air. If the truck is running fine now, I don't think you are going to see much difference with a rebuild though.


Stuart

the thing that makes me think the leaks may be a problem is when I give the eng gas there comes a certain point in the higher revs in 1st and 2nd gear where it seems like the rpms are hanging up without the eng power going up in tandem...maybe the mix gets too lean at high revs from the leaking? I thought about timing too but my throttle response is really good from an idle if you rev it abruptly and it idles incredibly smooth...I replaced the head a little while back which seemed to make it run a lot better...

you know you can audibly hear that carb sucking to beat the band when you gun it going down the road and it's sound strikes me that the motor is not being allowed to breathe near what it would like to...sounds like it's trying to suck up a tornado thru a straw... it has a small chrome air filter about maybe six inches across or so can't see that being all that much of a constriction...some of those twin carb set ups could be something to consider maybe...but since I am still trying to sell this truck I'd just like to have it running as good as poss without putting much $ into it...

Assuming you already cranked down the screws that hold the carb top to the body/float chamber (not too much or you'll strip the threads), try checking total ignition advance above about 3000 RPM and make sure it matches the specification for your engine.
If you haven't rebuilt a carb before, I'd recommend taking it apart on a clean, flat surface liek a table or bench top with nothing else around the working area or on the floor near it. Make sure there's plenty of light on the subject while you work. Disassemble it on top of a clean towel so parts (check balls, especially) don't roll away and get lost. Make notes and sketch a drawing or take a digital photo BEFORE you take each assembly completely apart. The instructions are usually very good but, if you've never done one before, there's nothing like seeing what YOUR carb looked like before you ripped it to pieces.
Good luck!

I had to rebuild the 1 bbl rochester in my 66 C-10 with a 250. The best place for photos, troubleshooting and repair is the GM truck shop manual for your year. I have the 63 manual and the 66 suplement. You would need only the 67 manual. Good Luck with your rebuild.

Could it be your exhaust system resricted causing the sucking noise & loss of power? The guys are right. This is a pretty basic easy to work on carb. It is actually fun to do. Make shure your power valve piston goes up & down & opens the ball in the power valve. Make shure the vacuum hole in the bottom of the carb lines up with the passage in the gasket. Like % said make shure the timing & advance are good.

Florida,

The leaking bowl won't effect your performance..it is in a "non-sucking" area. Don't let the sounds of the carburetor lead you astray. A full flowing carburetor is noisy, even a little old Rochester. You are using a small, aftermarket air cleaner..this exacerbates the noisy situation.

If the truck isn't running right, it will usually tell you. It will pop and backfire at high RPM's as it starves for fuel. It won't start correctly or will get horrible mileage. Remember what you are driving, an OLD truck with a low tech engine. If you want FAST, you will need to buy a brand new F-150...WHAT, HUH, @#%&?$

Stuart

Well -- You changed the head --- a task much more difficult than rebuilding that monojet carb, but like my old pappy always said about monojets; "I'd throw the darn thing away and buy a carburetor." I like the Holley / Weber 5200 on the 250. Small performance gain, and HUGE gains with cold starting and all around drivability!

Boo

If that 250 has the original type carb. it is not a monojet.

I have pics of the eng/carb I'd post if somebody wanted to see them (if I knew how:)

this truck starts easy and once warm idles smooth as silk...it's just that higer rev situation I was perplexed about...the leaking around the gasket is not bad visibly I just speculated it may have been messing with vacuum or mix...I can physically see my Vac advance function when I rev it and as I say once it's warm it's throttle response if you tweak it abruptly (you know as in vroom vroom real quick from idle:) is excellent...I know I have weak rings tho since it does burn some oil and still a bit of smoke when revved (not near as bad after the new head tho)...

the old thing is a cool old truck I enjoy driving...

irt this

<<< If you want FAST, you will need to buy a brand new F-150...WHAT, HUH, @#%&?$

Stuart >>>

remember I still have the other '67 C-10 with the 400 in it it moves on down the road at a great clip...but I still haven't found those #'s to id it's eng ...

thanks as always guys...