Farmall 300 upgrade with strange results

1958johndeere620 · Feb 24, 2015

Took the ole 300 in for some upgrades. I put a 1442 pertronix ignition system in with their high output coil. Also doing the 12 volt upgrade with delco alternator. I put an intake/exhaust manifold on from Stiener because I had a hole the size of a nickel in one of the exhaust tubes.The intake is the high output one offered by them. It is different only where the carb is supposed to get heat from exhaust side. They are not connected at the flange.Less heat = more power. They are not going to carry the stocker any more so I took what they had. After install my idle was way high. Around 1200 or better. I had to take the linkage apart at the governor connection point and take 2 full turns out then re attach the cotter pin. Why would the idle change so much by just replacing an intake and ignition? Did not even take carb off when doing the change over. Never touched anything. Kinda stumped.

D Slater · Feb 24, 2015

Anytime a manifold is changed you should go through and readjust the governor linkage to spec. Any change in the carburetor flange height will change the adjustment. Front throttle tube retainer is made so a little change in flange or governor housing height can be compensated for. Leave front retainer loose until carburetor and rear tube flange are tight, then tighten front tube retainer. Some aftermarket and other manifolds have a flange height off enough that the front of throttle tube won't line up properly.
Also did you check the ignition timing after installing the electronics?

1958johndeere620 · Feb 24, 2015

I did loosen the front or governor side of the tube so maybe that is where a small change took place. What I did to correct was take the pin out from the throttle shaft on gov end. Then backed off the lock nut on the adjuster block to turn it down 2 turns on the threaded rod that comes from the governor. That got it back where it should be. I wish I had tried to loosen that tube first, but o well live and learn. The timing was to advanced at the old setting. I had to retard it maybe 10 degrees or so. I will put a light on it when I am done. I also gapped the plugs out to 45 thou. Lots more to do and it won't stop snowing long enough to finish it. Thanks!!!

1958johndeere620 · Feb 28, 2015

Spent some time today getting the delco alternator hooked up and the correct size belt. I did the diode wiring setup as found on this site. Works well, found a diode on ebay. Is my .045 gap on my plugs to big? seems like it wants to stumble when I put a load on the engine. Runs super smooth at idle and smooth at high idle, but load the engine in a high gear and it will cut out. If my gap is not correct, what should it be. I have the high output coil from petronix with the 3 ohm internal resister.

High Octane · Mar 5, 2015

.028 plug gap seems to been the best performance from what ive seen. ive hooked the plug wire to coil tower, n adjusted the gap till i saw a nice spark kernal. also, indexing the plug gaps so they all face the piston heads helps too. good luck..

Farmall 300 upgrade with strange results

1958johndeere620

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D Slater

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1958johndeere620

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1958johndeere620

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High Octane

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