Ifitaintbroke Posted November 29 Author Posted November 29 18 minutes ago, viven44 said: Bradley, is there any chance the transfer slots are exposed? Apparently, that makes it impossible to maintain a stable idle. See below video. I have it set to play from 205 secs when the gentleman talks about this. No. I set them to square when I had the carb off. I will recheck when I replace the gaskets.
Ifitaintbroke Posted December 2 Author Posted December 2 I'm going to try getting this smoke test done today or tomorrow. I actually dreamed a couple of nights ago that I pulled the carb and the gasket was compromised. Maybe prophetic? 😆 1
Ifitaintbroke Posted December 3 Author Posted December 3 Problem is found and fixed. It was the carb. I tried the smoke test, which proved fruitless. Fiddled with it for a while, and got frustrated and walked off. I was at the point of giving up when suddenly it occurred to me that fuel starvation would show itself in the same way as a vacuum leak. Switched out the carb to my old 1406, and, after messing with it for a while, I got it to 800 rpm, 21 in/hg, and 13:1 afr. Better than I ever achieved with the AVS2. Keep in mind that the 1406 sat in the rain for over 3 years, was full of ethanol gas, and had been spray painted down the air horn. Not to mention the random kickdown linkage that was welded to the throttle bracket. I'm going to keep it for now. As for the AVS2, the only thing I can figure is that something is wrong with the idle circuit. It will probably end up being returned.
viven44 Posted December 3 Posted December 3 (edited) Great news.... I do think the 1406 might be on the smaller side for your 460, especially with it being built well (based on what I see on your signature)... I don't have a comparison with the 1406, but a few days ago I compared a 650 CFM AVS and my 750 CFM 1411, and I can say that the 1411 threw me back in the seat when the 650 couldn't. I'll try this one more time this weekend and report back. Maybe I didn't give the 650 AVS the advantage with the same step-up springs as I had on the 1411... but I am fairly comfortable at this point that the 750 CFM 1411 is an ideal choice for a 460... only thing I wished was it was an AVS so the secondaries could be fine-tuned ... This carb is on sale currently and it has the new annular boosters with better atomization that people are reporting good things about... it has definitely caught my interest but my 460s are pretty stock so probably not worth the spend Edelbrock 1913 Edelbrock AVS2 Series Carburetors | Summit Racing update: I'll take back some of what I said above. I dropped in the 650 AVS this evening again and used the larger step-up springs. It was really hard to tell the difference from the 1411 but one thing I can say for sure is that the 650 AVS's performance was no better than the 1411, after it warmed up fully, it was perhaps a tad behind. I played around with the secondary adjustment to no avail. Edited December 3 by viven44
Gary Lewis Posted December 3 Posted December 3 Glad you got it figured out! I pulled a 750 Eddy off Big Blue when I had the carb'd engine in him and put a 600 Eddy on. From a stop I couldn't tell any difference in full throttle, but the 600 might have been slightly better in part throttle. The only real difference I could tell was above 4000 RPM where the 750 was stronger.
viven44 Posted December 3 Posted December 3 (edited) @Ifitaintbrokeyou won't believe but I did an adjustment on the 650 AVS secondaries, set it back to factory spring tension. When I got back home the Bronco barely idled. The idle RPM came down to 350 or so!! I pulled up to the driveway barely without it dying. The vacuum gauge was slightly over 10".. when I covered up the area over the primaries in the air horn, the idle recovered... just similar to what you said. The prior owner of this carb had the same problem when things go warm..... really strange... something wrong in the idle circuit. Your 650 AVS and the one I just acquired. Not sure why things lean out big time randomly. Obviously the clean up I did wasn't good enough.... I need to go clean out idle passages with a wire... check the air bleeds, etc in the idle circuit But sounds like yours was a new carburetor ? Surprisingly defective out of the box Edited December 3 by viven44 1
Ifitaintbroke Posted December 3 Author Posted December 3 17 hours ago, viven44 said: @Ifitaintbrokeyou won't believe but I did an adjustment on the 650 AVS secondaries, set it back to factory spring tension. When I got back home the Bronco barely idled. The idle RPM came down to 350 or so!! I pulled up to the driveway barely without it dying. The vacuum gauge was slightly over 10".. when I covered up the area over the primaries in the air horn, the idle recovered... just similar to what you said. The prior owner of this carb had the same problem when things go warm..... really strange... something wrong in the idle circuit. Your 650 AVS and the one I just acquired. Not sure why things lean out big time randomly. Obviously the clean up I did wasn't good enough.... I need to go clean out idle passages with a wire... check the air bleeds, etc in the idle circuit But sounds like yours was a new carburetor ? Surprisingly defective out of the box Brand new, and the issue didn't appear immediately.
ArdWrknTrk Posted December 4 Posted December 4 I'm glad your truck is idling properly but I wonder what is wrong with the idle circuit.. I know that the AVS I sent to Vivek didn't have an idle problem. It lost the accelerator pump and was a little lacking above 5,300 rpm. 😂 Otherwise it was a good carb once I cleaned it up (and Gary can attest it was awful when I bought it) My mileage has definitely dropped since I installed the 750 Holley
Ifitaintbroke Posted December 4 Author Posted December 4 12 hours ago, ArdWrknTrk said: I'm glad your truck is idling properly but I wonder what is wrong with the idle circuit.. I know that the AVS I sent to Vivek didn't have an idle problem. It lost the accelerator pump and was a little lacking above 5,300 rpm. 😂 Otherwise it was a good carb once I cleaned it up (and Gary can attest it was awful when I bought it) My mileage has definitely dropped since I installed the 750 Holley Not sure either. Had a brand new 10 micron fuel filter as well.
Ifitaintbroke Posted December 4 Author Posted December 4 Another problem found. Apparently the #3 and #4 spark plug wires were loose from when I put in the evaporator core. 😑 I'm amazed that it ran so well. It didn't have any noticeable skip or miss, and I have driven it around the yard several times. 1
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