Ford F834 Posted August 25, 2020 Author Share Posted August 25, 2020 That's great news! Did you ever solve the problem that came up every once in a while? Seems like the engine would die and yet restart? Might this carb solve it? Gary, that is one of the problems I am hoping will go away with this new carb. It was infrequent, so time will tell if this eliminates it. The old carb also suffered from nose dive idle when I pushed in the clutch and rolled to a traffic stop (had to set racing idle to prevent stall). This seems to be gone, fingers crossed. Also, about 70% of the time it would diesel/run backwards when shut off. This also seems to be fixed. Link to comment Share on other sites More sharing options...
Gary Lewis Posted August 25, 2020 Share Posted August 25, 2020 Gary, that is one of the problems I am hoping will go away with this new carb. It was infrequent, so time will tell if this eliminates it. The old carb also suffered from nose dive idle when I pushed in the clutch and rolled to a traffic stop (had to set racing idle to prevent stall). This seems to be gone, fingers crossed. Also, about 70% of the time it would diesel/run backwards when shut off. This also seems to be fixed. If it fixes all that it'll be a miracle. Especially for the price! Link to comment Share on other sites More sharing options...
1986F150Six Posted August 25, 2020 Share Posted August 25, 2020 If it fixes all that it'll be a miracle. Especially for the price! That is very promising news, Jonathan! Link to comment Share on other sites More sharing options...
Ford F834 Posted August 25, 2020 Author Share Posted August 25, 2020 That is very promising news, Jonathan! Thank you David! And thank you for spotting it on eBay and sending me the link 🙂. Once again your tireless search talent has greatly helped me Link to comment Share on other sites More sharing options...
Ford F834 Posted August 31, 2020 Author Share Posted August 31, 2020 Thank you David! And thank you for spotting it on eBay and sending me the link 🙂. Once again your tireless search talent has greatly helped me Folks... I have discovered a problem.... As you may recall I thought my timing was set over-advanced. It was. A lot. I moved it back to about 14* and went for a ride. It ran like absolute crap 💩. It behaved like I had the choke on. I got home and pulled the vacuum hose and found that I have absolutely NO Venturi vacuum out of the single vacuum port provided on this carburetor. I do not know if this is a defect, or perhaps a packing oil issue? I may investigate more later, but for now the solution is to run the distributor off of full manifold vacuum. I think I would get smoother idle with Venturi vacuum, but manifold vacuum is working. It is running better than it was with crazy advanced static timing. Link to comment Share on other sites More sharing options...
Gary Lewis Posted August 31, 2020 Share Posted August 31, 2020 Folks... I have discovered a problem.... As you may recall I thought my timing was set over-advanced. It was. A lot. I moved it back to about 14* and went for a ride. It ran like absolute crap 💩. It behaved like I had the choke on. I got home and pulled the vacuum hose and found that I have absolutely NO Venturi vacuum out of the single vacuum port provided on this carburetor. I do not know if this is a defect, or perhaps a packing oil issue? I may investigate more later, but for now the solution is to run the distributor off of full manifold vacuum. I think I would get smoother idle with Venturi vacuum, but manifold vacuum is working. It is running better than it was with crazy advanced static timing. If I remember correctly, some of the YF/YFA's had a strange ported vacuum that only reached ~10" of vacuum at cruise. Might that be what you have? Link to comment Share on other sites More sharing options...
Ford F834 Posted August 31, 2020 Author Share Posted August 31, 2020 If I remember correctly, some of the YF/YFA's had a strange ported vacuum that only reached ~10" of vacuum at cruise. Might that be what you have? Hmmm... I guess I should track down my vacuum gauge. Even when I rev it up to say 2,500 rpm I can’t feel anything at all with the hose on the tip of my finger though. Also, there is no change in how it runs with the port unplugged (simulating a leak). I didn’t think to blow through from the distributor end of the hose to see if it is blocked. I should check a few more things tomorrow. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted August 31, 2020 Share Posted August 31, 2020 Hmmm... I guess I should track down my vacuum gauge. Even when I rev it up to say 2,500 rpm I can’t feel anything at all with the hose on the tip of my finger though. Also, there is no change in how it runs with the port unplugged (simulating a leak). I didn’t think to blow through from the distributor end of the hose to see if it is blocked. I should check a few more things tomorrow. There should be less and less vacuum as you open the throttle. Ported vacuum should start as soon as you crack the throttle plates into the transfer ports (hence "ported") I'm hoping this is easily resolved, Jonathan! Link to comment Share on other sites More sharing options...
1986F150Six Posted August 31, 2020 Share Posted August 31, 2020 If I remember correctly, some of the YF/YFA's had a strange ported vacuum that only reached ~10" of vacuum at cruise. Might that be what you have? Gary, we saw this on the Carter YF on my truck. It had about 5" Hg @ idle and never exceeded 11". Link to comment Share on other sites More sharing options...
Gary Lewis Posted August 31, 2020 Share Posted August 31, 2020 If I remember correctly, some of the YF/YFA's had a strange ported vacuum that only reached ~10" of vacuum at cruise. Might that be what you have? Gary, we saw this on the Carter YF on my truck. It had about 5" Hg @ idle and never exceeded 11". Yes! That's where it was. Jonathan - I'd be tempted to put a bit of compressed air on that port and see if it is just clogged. It is really just an opening into the low pressure area, so it wouldn't take much grease to clog it. Link to comment Share on other sites More sharing options...
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