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Subject: Carb (I think)

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Rick Douglas    Posted 02-26-2021 at 15:30:27 [URL] [DELETE]        [Reply] [Email]  
  • Carb (I think)
  • 'Ole Henry, '50 8N, has a perpexing problem. He just has trouble starting after sitting a few days. First try will sputter and die. After that, it just won't start. It seems to me that gas is not getting drawn-up to the cylinders. Here' some "hints" that may help solve the puzzle:

    Even after turning over for quite a while, the plugs are dry.
    Plenty of spark.
    Carb rebuilt about 20 hours ago. Clean inside.
    Float is good. Pull off the air inlet tube, and about a thimble of gas runs out.
    Condfident the jets are set properly
    Always starts with starter fluid
    No manifold leaks.
    Winter or summer, putting a heat gun on the carb for a few minutes sometimes helps.
    Choke plate is good.
    No air obstructions.

    Any suggestions would be very much appreciated.

    Den N Ms    Posted 03-03-2021 at 10:27:29 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Carb (I think)
  • Rick,Drain your gas tank and get some ethanol free gas,racing fuel or aviation gas and try that to see if it starts right up.

    Rick Douglas    Posted 03-03-2021 at 17:51:15 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Carb (I think)
  • Great idea! I'll give that a try this weekend.
    Thank you, kind sir.

    Tim Daley(MI)    Posted 02-28-2021 at 07:05:24 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Carb (I think)
  • You still haven't answered if it is a front or side mount and if 6V or 12V. Plugs are supposed to be dry as Bruce said. Forget "20 hours" on a carb rebuild -what does that mean/prove? FACT: 99.98% of all non-starting issues are due to mucked up electrical systems regardless if 6V or 12V. Just because your battery is 6V or 12V doesn't mean it is wired correctly for that system. Often electrical issues turn out to be fuel issues and vice versa. ONE STEP AT A TIME. 1) get battery tested at a shop. A weak and/or a dead battery is a major cause of non-starting. Applying a trickle charger will do nothing. If battery is dead and needs replacing, invest in a good brand, not a bargain house one that can be dead out the door. While the shop tests or replaces the battery, leave it on a shelf til fuel, electrical, and wiring are verified. Perform the fuel flow test. How and where did you set the float to and did you install the needle valve correctly with the gasket and was it tight? Do you shut off the Sediment Bulb Valve when you park the tractor? There should be no fuel flowing out the carb throat to air cleaner. Are you seeing fuel or starting fluid? 2) Tune-Up; points set and TIMED correctly? When we know if front mount or side mount we can get into more detail.


    Tim Daley(MI)


    Lynn Patrick    Posted 02-27-2021 at 09:07:07 [URL] [DELETE]        [Reply] [Email]  
  • Re: Carb (I think)
  • I had a '50 8N that acted the same way. If I didn't keep it running the first time it fired I had to use ether. It had good spark, "good enough" compression that it should run (over 100#), new plugs, points, etc, it just would not start. Finally went thru ignition again being VERY careful to get points & timing set EXACTLY TO SPECS, & it solved the problem solved.
    A few thous off on points, couple degrees off on timing, & possibly loose distributor bushings can make a HUGE total difference!

    Rick Douglas    Posted 02-27-2021 at 10:03:06 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Carb (I think)
  • Thanks Lynn. That's one area I didn't consider. Just got focused on the fuel system. It may take a couple days, but will post results.

    Bruce(VA)    Posted 02-26-2021 at 16:11:59 [URL] [DELETE]        [Reply] [Email]  
  • Re: Carb (I think)
  • First, you need to tell us if itís 6v or 12v and if it has a front or side distributor.

    Next, plugs are supposed to be dry. If they were wet, the engine is flooded and it will never start.

    These tractors are pretty simple machines; itís usually pretty easy to get them running with some basic troubleshooting steps. You can:

    1. Replace every part you can until it starts or you run out of money.

    2. List every possible cause of the problem and then randomly pick your favorite to check. It could be your coil. Or your ignition switch. Or about 10 other things.


    3. Like diagnosing any other equipment failure, take a step-by-step approach, working from the most likely to the least likely, one system at a time.

    Iíve tried all three approaches. The third one always worked for me.

    I might not be able to tell you why your tractor isnít running, but I can tell you how to figure it out for yourself.


    You could have a spark issue.


    You could have a fuel issue.


    Donít guess. Troubleshoot. See tip # 13 at the link below.


    You need to answer 2 questions before you do anything else:


    With the bolt in the carb bowl removed and the gas on, will the fuel flow fill a pint jar in less than 2 minutes?


    Next, get out your adjustable gap spark checker * , open the gap to 1/4", hook it up, turn the key on and crank the engine. Does the spark jump 1/4"? Post back with the answers.


    And do not buy a new part for the tractor until you can answer this question: how do I know the part on the tractor is defective?

    Once you narrow the problem to spark or fuel, post back and tell us what you found (and how you found it) and you will get plenty of help to get your tractor running.

    * Don't own an adjustable gap spark checker? Buy one! Not a test light! Until then, take an old plug, open the gap 1/4" ground it to the head & look for spark. Itís not the color of the spark that counts; itís the distance it jumps.

    https://www.autozone.com/test-scan-and-specialty-tools/ignition-tester/oemtools-adjustable-ignition-spark-tester/10257_0_0?cmpid=PLA:US:EN:AD:NL:1000000:TLS:71700000043798748&gclid=Cj0KCQiAovfvBRCRARIsADEmbRKBdAvAmtFfOvYiYXR7T6NYiW57uyv5-dEKjVT_h2KogQNUUMsRixYaAlU3EALw_wcB&gclsrc=aw.ds


    Rick Douglas    Posted 02-26-2021 at 19:01:46 [URL] [DELETE]        [Reply] [Email]  
  • Re: Carb (I think)
  • Bruce;
    Thanks for your repy and suggestions. Strong blue arc at 1/4 inch gap. 6V with front distributor.
    Fuel flow is 1 pint in 1 min 20 seconds.
    Just tried again after 5 hours without a sputter.
    A small shot of starter fluid and it starts and runs good.

    Tip #14 says to pull on the throttle arm and there should be some resistance from the governor, witch I don't feel. I don't know crap about governors, so the research begins.

    I'm wondering if a bad adjustment or bad governor could cause hard starting.

    Any thoughts from anyone?

    Rick Douglaz    Posted 02-26-2021 at 20:35:41 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Carb (I think)
  • Sorry. The governor is working well. Resistance from the throttle arm and rpm increases with just a small movement with the throttle lever.

    Still will only fire with starting fluid.

    Jack - Iowa    Posted 02-27-2021 at 08:01:58 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Carb (I think)
  • Have you checked for a vacuum leak? Spray your starter fluid around the manifold including the joint where the carb attaches while trying to start it. A helper helps!

    Had similar problem on my 2N. Carb attachment gasket had dried out/worn out and revealed someone had drilled an extra hole through the carb flange. A little epoxy and new gasket, problem solved.

    RickDouglas    Posted 02-27-2021 at 08:43:46 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Carb (I think)
  • Thanks Jack, but I've checked that. I'm also from Iowa (Anamosa). Where are you located?

    Jack - Iowa    Posted 02-28-2021 at 07:53:49 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Carb (I think)
  • Live in Des Moines now. Originally from Henry County and still have 20 acres there. Sold the rest of the original farm a little over a year ago.

    HCooke    Posted 02-26-2021 at 19:35:41 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Carb (I think)
  • L ow compression and cold weather will cause hard starting.

    Rick Douglas    Posted 02-27-2021 at 08:47:39 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Carb (I think)
  • Thanks for the reply. I haven't done a compression check, but the engine feels strong with no lack of power. Problem also exists in summer.

    JMOR    Posted 02-27-2021 at 11:44:58 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Carb (I think)
  • do the compression check

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