1 barrel rochester carb 1967 problem

[VWNate1]

Sadly that particular anti - diesel valve is no longer available that I can find, IIRC (possible, stop laughing) it was only used in '86 & '69, I had to cobble up the one shown to work, standard Ignition and other (Well, maybe) still make it .

I don't know if it's possible to get a Radio/TV Repair Shop to solder a wire on to the one you've got, often when they failed it was internally and not repairable .

As mentioned , these solenoids were band aids but they do work just fine and were used on many ir not most American carburated engines for decades .

Some used vacuum pots instead of electric .

You're getting closer now, don't quit ~ I find good Dwell / Tachometers at yard/tag sales for $5 ~ $10 all the time, I'm sure you can too and once you have one you'll be far more accurate in your work .

DO NOT pay one penny for one unless you personally test it out .

I hope you understand that you don't need a choke stove because of the manual choke you now have .

[Steeveedee]

Also, since (IIRC) the smog equipment is removed, and it isn't dieseling after you shut it off, you just may not need it. You can shut it off in gear, and then put it in park, if necessary, to keep it from dieseling.

[G8rN@te61]

Ok so if I have manual choke don't need choke stove got it. What about the vacuum pull off thingy? So I turned the outside of the solenoid do I need to turn the inside of it any?

Now that I am thinking about it this truck "grew up" in Montana high altitude mile above sea level. Probably tuned to that elevation so now that I am only around 1000 feet above sea level here in NC its probably acting up. Should I mess with the mixture screw?

Yes I was leaving in gear to turn off but to me that means the engine wasn't tuned correctly.

[VWNate1]

Good morning ;

No, the vacuum choke pull is also unnecessary when you're using the manual choke .

Yes, you should get a long thin screwdriver and _s_l_o_w_l_y_ turn the mixture screw in until the engine begins to miss during a hot idle, then turn it back out 1/4 turn .

If it begins to stumble as soon as you turn it in, turn it out until it runs smoothly and rev. it a bit to clear out the plugs , allow to idle again then slowly turn it in until you feel the engine begin to miss ~ if the engine is really healthy it's begin to vibrate before it misses, stop then and back out just enough to get a smooth idle .

When you turn the solenoid you should always and only turn it by turning the threaded part that screws intoi the carby proper ~ turning the larger, round part is what kills these and is why they changed the design so quickly .

There's a hexoganal part right where the threaded part meets the barrel part - IIRC 1/2", use an open end wrench to turn it .


Wish I was there to lay hands on, i6 engines are much smoother than V8's and a true joy to drive once they're right .

[G8rN@te61]

thats the screw bottom left below choke pull off correct?

[VWNate1]

Yes, the bullet headed screw with spring in post # 49 .

Turning it clockwise leans the mixture, counter clockwise richens it and it's *very* delicate so never crank it home when making the initial setting .

A 1/8 turn is a lot when you're close so go slowly and gently, yes I know the goofy design is carefully set to heat up and fry your fingers !~ you should see mine after 50 years of twiddling the damn things .

If you can lay hands on a vacuum gauge that is useful too when adjusting hot idle .

Always remember : the tuning of any engine works like the face of a clock : 12:01 is where you begin and 11:58 is when you touch the carby ~ everyone always wants to touch the carby first , carbys never go out of adjustment unless touched so they're dead last in the scheme of things .

[Steeveedee]

Originally Posted by VWNate1

Yes, the bullet headed screw with spring in post # 49 .

Turning it clockwise leans the mixture, counter clockwise richens it and it's *very* delicate so never crank it home when making the initial setting .

A 1/8 turn is a lot when you're close so go slowly and gently, yes I know the goofy design is carefully set to heat up and fry your fingers !~ you should see mine after 50 years of twiddling the damn things .

If you can lay hands on a vacuum gauge that is useful too when adjusting hot idle .

Always remember : the tuning of any engine works like the face of a clock : 12:01 is where you begin and 11:58 is when you touch the carby ~ everyone always wants to touch the carby first , carbys never go out of adjustment unless touched so they're dead last in the scheme of things .

The carb stuff- so true! I can't count the number of people over the years who complained about the carburetor, only for it to be ignition, 99% of the time. That's when points were king, though. Once the electronic ignitions gained some ground, a lot of ignition troubles went by the wayside.

[VWNate1]

"Carburetor" is a French word meaning : LEAVE IT ALONE .

[Steeveedee]

Originally Posted by VWNate1

"Carburetor" is a French word meaning : LEAVE IT ALONE .

Too true! I think that if people did that, Holley and Edelbrock would be out of business, though! Except for some racing applications, of course.

[G8rN@te61]

ok so I turned the mixture screw as instructed and think I got it in a good spot. I actually had to turn it at least 4 times until it started to shake miss like you said. timing still at 10˚. I noticed that the rpms increased ever so slightly and after revving it out a few times it seemed to settle in a good spot.

HOWEVER. When I was messing with PCV valve and removed it to re-seat it better it completely stalled out while running. So I turned the mixture back approx 1.5 turns and it doesn't happen now. This normal?

[VWNate1]

No, that's not normal .

Probably the PCV hose is cracked or hard, causing air leaks .

The DCV hose is a special thing, most FLAPS carry it, you have to ask by size or take the olf PCV valve in to match it .

A PCV valve is in fact, a _calibrated_ air leak into the intake manifold between the carby and the engine as the *instant* a PCV valve goes off spec. for any reason (leaks or plugs for example) the idle will get scrwed up .

? Remember when I said the carby is the very last thing to touch ? .

If your PCV valve is metal, you can soak it in a variety of solvents, carby cleaners, alcohol, acetone (! Acetone is *very* nasty stuff, use WITH CAUTION) , etc., etc. .

It sounds like you're getting very close .

I've not forgotten about your request for the HEI ignition relay, I'm just physically FU-BAR right now and so will need a hand .

[G8rN@te61]

but it only happened when actually removed the PCV valve from the valve cover to re-seat it..

[VWNate1]

Yes and you said the problem persisted, this usually indicates the hose cracks or was too hard to maintain a good seal after it was flexed.....

I'm just covering the basics here, 99 % of the time all issues are quite simple and will be fixed by something basic .

[G8rN@te61]

Apologies. I misspoke or was unclear.. When I re-seated it it ran started again. I turned the mixture screw back so it would run disconnected. You should be able to remove it and the engine keep running correct? Albeit roughly. At least I have been able to on other vehicles.... doesn't mean they were tuned correctly though right lol.

Yes its usually always basic. I do appreciate your help and I think I've just about got it there. Then its on to the HEI!!

[VWNate1]

If you open the hose to the manifold, the engine should speed up briefly then refuse to idle and die .

If you just pull the PCV valve out of it's grommet, it shouldn't make much difference, a little bit but not much .

By the time you're done here you'll have a good running rig and know how to make other folks rigs run sweetly too ~ not as tire burning as a V8 but in general use i6's are *much* nicer drivers plus better economy and so forth .

My Brother is coming Thu. or Fri., I'll see if he'll help me snap a photo of the HEI relay, it's very simple, I mount it in the ground strap screw just above and to the right rear of the engine .

This strap is often gone missing and causes other issues, poor lights, bad gauge readings, etc., etc.

[ultimatejc]

Originally Posted by VWNate1

Here are the part #'s for a 1968 with a manual choke :

Alternate/OEM Part Number(s): 17055531, 7028006, 7028007, 7028010, 7028011, 7028012, 7028013, 7029007, 7029011, 7029012, R1M

I hope this helps, you may have to fiddle the linkage .

Got it installed and running. Just need a new air cleaner as my oil bath won’t fit on this one.

Any recommends for air cleaners for this carb?
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[VWNate1]

I prefer the stock ones as they filter far better than those K&N things do .

? can't you find one of the stock Sedan ones locally in a junkyard or auto jumble nearby ? .

I have some spares but they're beat up and I'd not want to mail off junk that won't quite fit .

No body likes the oil bath ones, they filter better than anything else, it took me a while to find one, I use ATF in the oil cup to make it self cleaning ~ the amount of dust and crud that accumulates when you use ATF is astounding .

[ultimatejc]

Originally Posted by VWNate1

I prefer the stock ones as they filter far better than those K&N things do .

? can't you find one of the stock Sedan ones locally in a junkyard or auto jumble nearby ? .

I have some spares but they're beat up and I'd not want to mail off junk that won't quite fit .

No body likes the oil bath ones, they filter better than anything else, it took me a while to find one, I use ATF in the oil cup to make it self cleaning ~ the amount of dust and crud that accumulates when you use ATF is astounding .

I’ll measure it up and hit up some junkyards to find one that fits. Appreciate the reply!!
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[G8rN@te61]

I actually have been looking to replace my stock one with a chrome assembly and saw the stock setups sold on summit.

I also have a really cool offset assembly but its missing the bottom half.

[VWNate1]

Be aware that the chrome ones are all Chinese made of tin foil and rarely last very long .

I know they look cool, just toss the old original one in a box with the wingnut and so on, sooner or later you or someone will want it .

[cpnbnanamn]

Sorry to resurrect an old thread.. but I could use some guidance. I'm still running the original 250 ci with that carb, rebuilt it last year, and can't seem to get the idle/mixture right. Every time I give it just a little gas, it bogs for a second and then takes off. Can't seem to find a good process on how to tune 'em right. I understand the theory and priciples, but haven't mastered the voodoo magic yet.
This is in place till I get my 406 done, and ready to install, so in the meantime, I want it to run right. Any help would be appreciated.

[VWNate1]

NO Problem ! .

The flat spot off idle is very common and you must take the steps to ensure everything else is *perfect* before touching the carby or you'll chase your tail endlessly and hate the rig .

You'll need a 12 volt, inductive timing light ($30 new @ O'Reilly's), a dwell tachometer (pawn shops have these cheaply) and a vacuum gauge (another $5 used tool at the pawn / thrift shop) and some new vacuum hose .

Have some patience, we'll walk you through it .

[cpnbnanamn]

Originally Posted by VWNate1

NO Problem ! .

The flat spot off idle is very common and you must take the steps to ensure everything else is *perfect* before touching the carby or you'll chase your tail endlessly and hate the rig .

You'll need a 12 volt, inductive timing light ($30 new @ O'Reilly's), a dwell tachometer (pawn shops have these cheaply) and a vacuum gauge (another $5 used tool at the pawn / thrift shop) and some new vacuum hose .

Have some patience, we'll walk you through it .

Thanks.. I can use all the help I can get. One question (of many, I'm sure).. I realized last night that I hadn't don't a proper tune-up.. plugs, rotor, cap, wires, etc. In researching what I need I was told that I needed R44XLS plugs. Umm.. they don't fit the head. The threads do, but th hex is too big to get a socket on, once it's seated. What came out of it are R45TS. Parts x-reference says that's not supposed to be there. Which is right?

[Steeveedee]

There two types of spark plugs on these. If the plugs you took out only look worn, just go back with the same plug size when you replace them.

[cpnbnanamn]

Hey Steevee
Yeah, that's kinda what I'm ending up doing. I broke one last night, trying to get it out. They were kinda rusty, and I'm betting that's what is making it hard to get them out. The plugs look fouled, but as I'm not sure as to when they were changed last, I'm doing it, and a full tune-up anyway.