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Old 07-15-2015, 05:03 PM   #8
Blessed66
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Join Date: Oct 2012
Location: Tyler, Texas
Posts: 217
Re: Some questions (pictures soon).



Recognize this? Yeah, me neither. I do love that these diagrams don't really add up, sometimes. Here's the issue; I've ripped out much of the emissions and am currently working on rerouting the lines needed to stop my vacuum issues. Curently, I cannot get this truck to even run. Help! I know I have some work to do on my own, but I could sure use a hand in double-checking this set-up. Pictures coming in hot!



I've replaced the PCV Grommet (47062 Dorman/Help!) and the Valve was still ok, so I capped off the line running to the canister (It's gone). The exposed AIR tubes and check valves are an exhaust leak, basically, but they shouldn't be keeping this truck from running, right? It's not like a blown manifold gasket keeps your truck from running.



I did go back and cap the exposed EGR vacuum line on the valve and it tried to start for a moment, but wouldn't continue running. I ran a fresh line from what I believe is a ported vacuum on the carb to the ignition advance (you can see port in previous photo on L side). It made no difference - the only change was when I capped the EGR valve. Exposed AIR Valve, again. It did run like this for a bit a day or two ago. Sounded pretty terrible, honestly. I used to love open headers, too. Bet I won't anymore.



I do not like this thing. I gotta get under the truck and find the other bolt holding it on so I can fully rip it off the truck. I had a really odd knocking noise when it was running with all of this hooked up. I had read that this pump can sound like knock when it fails. I may be wrong (probably) because the knock was never constant with the engine running over idle. Sounded like a loose bracket somewhere.



Do I need to cap these Ported Vacuum switches? I doubted it because if there's no signal line going to the switch for distribution, it makes sense that there would be no vacuum leak if nothing was hooked up, right? I know these things do wonderfully to distribute vacuum without having dozens of ports on the carb itself, but I really only want vacuum to my P/B Booster, Transmission, Ignition and PCV system. Cruise would be nice, but I don't really care if I have it or not.



This is a heck of a mess. I put a cap on the back of the diaphram next to the EGR. Memory serves it's a vaccum brake for the secondaries. Keep the opening of them smooth. No change to the no-start condition. There is a small line going to the back of the carb from the diaphram so it should still be getting vacuum, but I couldn't tell if the nipple coming off the "top" was open or an adjustment (blind nipple) of some sort so I capped it just to be safe.

Thoughts? Suggestions? The odd part about this was the truck did start up and run with a majority of these ports unplugged. But now, it won't? Kinda irritated, of course, but maybe someone can steer me in the right direction.

Oh, and the front left wheel (for sure, haven't checked the right wheel) is frozen. No wonder I almost killed myself pushing the truck. I'll get to that after I get it started up and atelast not running so dang badly. I know a carb rebuild is likely in the future, and I may have found a guy nearby to do it who I trust, but I know this truck was running about a week ago. Ran bad, but it ran. I need to get it back to that baseline first.
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1984 GMC, LWB Fleetside, 305/350 - Currently Doing TBI Conversion
1966 GMC, SWB Stepside, 350/200-4R - Currently waiting patiently.
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