Carb tuning and frustration...

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mwebfj60 said:
That's the reason I asked if you pulled the canister purge line off and capped the inlet. This is a simple check that takes all of 5 seconds. With your vacuum at 17 at your altitude, I wouldn't suspect a manifold leak at the head, of course that reading is at 1k right? Did you set timing at 1k or 650? You're not recurved so your mechanical advance is a little too quick for a desmog. At 1k it may be advancing a hair. Recurve is just a matter of swapping in different springs in the dizzy and making sure the advance limiter bushing is there( mine was long gone). I also widened my air gap just a slight hair while tuning the distributor. That plate that the vacuum advance hooks to that swivels(can never remember the name) gets pretty gummed up and sticks in certain positions. If you're pulling the carb, check the power piston slides easily, float level, both balls are there and in their right spots, blow some compressed air through the passages, if you broke it all the way down on the rebuild, check the gaskets that go in between the linkage part of the carb, the spacer, and the body of the carb. It's confusing to get them right and make sure the holes in the gaskets line up with the ports. Those are the thoughts that I came up with.
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Way better description than I could ever come up w/. ;)
That piece that the block sits on and the gap is measured against the cam is the breaker plate. I just did all that to mine. And yea my bushing was gone too.
 
@mwebfj60 you are talking about the PCV port that come from the plenum spacer below the carb correct?
 
NeverGiveUpYota said:
Way better description than I could ever come up w/. ;)
That piece that the block sits on and the gap is measured against the cam is the breaker plate. I just did all that to mine. And yea my bushing was gone too.
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So you guys are talking INSIDE the dizzy then, no longer talking about the carb? Never pulled the dizzy, have only replaced the cap and rotor as needed (once when I got the truck and then after the rebuild).
 
gregnash said:
So you guys are talking INSIDE the dizzy then, no longer talking about the carb? Never pulled the dizzy, have only replaced the cap and rotor as needed (once when I got the truck and then after the rebuild).
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Yeah the insides. As shown in the pics on my thread.
 
gregnash said:
@mwebfj60 you are talking about the PCV port that come from the plenum spacer below the carb correct?
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The pipe off the black insulator under the carb is not the pcv port. That pipe would have a hose connected to it and it would go the a driver side vcv (mine is capped). The other pipe that points to the firewall that has a hard hose connected to it that then goes over the valve cover is the one that goes to the pcv. Again, pixs on my thread. That pipe was totally blocked when I took my manifolds off.
 
Correct
gregnash said:
@mwebfj60 you are talking about the PCV port that come from the plenum spacer below the carb correct?
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Not the PCV port, the canister purge that comes from the VCV.
 
Ok gonna have to take a look when I get home. Hard to imagine all these items when looking at my phone while grocery shopping. That or someone post pics they are talking about LOL!!
 
It's like 20 degrees outside and windy as f... no way I'm going into the garage... so my couch is way too cozy after a day at work. I don't have pixs nor those parts in my computer room, if they were I'd snap you pixs.
 
Found this on my phone.... the port is circled in red.

IMG_3988.webp
 
That's a good thread on the diz and recurving yourself. And I saw I liked some of the posts in the past so apparently I've read it through.
 
Hey also while the vac advance is being mentioned again... which port on the pot on the side of the diz are you using? The inner is the primary (~14) but some who aren't recurved will use the outer so the advance is less (~7). On mine when I pulled the pot off only the primary port works... luckily now that I've recurved I 'should' be okay since I only need the primary.
 
No matter how "messed up" the distributor curve may or may not be, timing set at the timing ball on the flywheel will be 7° BTDC. If the pointer lines up with the timing ball at idle, the chronic high idle isn't timing related.

Vacuum leaks don't raise idle. They just make the idle rougher. Pull a vacuum hose to see for yourself.
 
I have followed your responses on many occasions , and you are usually right on , thanks for your input:).
 
Don't have time to read all the responses.

First set the basic parameters:
Adjust idle speed screw to preferred idle speed.
Adjust idle mix screw to give highest/best idle speed.
Adjust idle speed again.
Set base ignition timing to 7*. If HAC is disabled, add +1* per 1000' above sea level.
Adjust idle speed again.

HTH
 
Well not going to be troubleshooting this today. So far we have gotten 4" down here (Tahoe has received 14"+) and it's still going.
 
Hey Greg,
I JUST got a carb and dizzy and ignitor from Jim C. I had it sent to him by Georg when my TBI puked and died. Unfortunately it took him a little longer to get to it than I had, so I had my ECM rebuilt in the mean time. SO>>> I have a carb tuned and rebuilt by Jim set for 4500ft elevation that I will be selling asap. Send me a PM or shoot me a text you should still have my digits. If your interested.
 
Thanks @tat2matt but I may go the way of a Trollhole if I end up replacing the carb. Been really looking at the AFI system, that's what you installed isn't it?
 
I did install the AFI system. Overall I would recommend it. I had my ECM fail on a trail outside Estes Park. In the end it cost me $125 to have the ECM rebuilt. I would be inclined to do the same system but from the junk yard.
 
EFI on a morning like this (20* and 6" of snow on the cruiser) would have been nice instead of pumping the gas a billion times for her to finally wake up. But then again partially my fault as I knew I should have gone out there and started her yesterday..

FJ40Jim said:
Don't have time to read all the responses.

First set the basic parameters:
Adjust idle speed screw to preferred idle speed.
Adjust idle mix screw to give highest/best idle speed.
Adjust idle speed again.
Set base ignition timing to 7*. If HAC is disabled, add +1* per 1000' above sea level.
Adjust idle speed again.

HTH
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So based on your method @FJ40Jim you don't touch the timing until AFTER you have set the idle speed?
 
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