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Technical Flathead lacking power

Discussion in 'Traditional Hot Rods' started by beezil007, Jan 21, 2018.

  1. beezil007
    Joined: Sep 8, 2012
    Posts: 12

    beezil007
    Member

    I have a 1947 Ford Super Deluxe Tudor I have had for a few months. Of late the car seems to struggle to get off the mark very well without me riding the clutch. The car has a PM7 Manifold with twin 97 carbs it is running an electric fuel pump also and a standard Carb distributor. Is there somewhere I should be looking to fix this issue. Would it be spark or fuel I am thinking fuel carb issue? Thanks for any assistance


    Sent from my iPhone using The H.A.M.B. mobile app
     
  2. Red98422
    Joined: Jan 21, 2018
    Posts: 4

    Red98422

    Any recent changes to the fuel/air? Is it sputtering or bogging? Do you have a fuel psi guage? If so what is your readings at WOT and idle? What does the sight glass look like? I’m going to be honest and state I have no idea what a “97” carb is. Help us help you, please tell us as much as you can with what you know, even if it seems to be a “no brainer” to you. Does the problem happen consistently? For instance are there any elevation changes, is it only up/down hill? What’s the timing of the engine in question? Distributor, is it points? What is the last time the gap has been checked? The more detailed the information the better that you
    Can be helped and back on the road at WOT!!!
     
  3. Another Newby trying to act like a Mr know it all...and don't even know what a "97" carb is...
    Hey Red !!! do some more reading before trying to answer questions or maybe you are on wrong forum.
     
  4. dan31
    Joined: Jul 3, 2011
    Posts: 1,097

    dan31
    Member

    Yes, any info you can give will be helpful to narrow down the problem. Is it just down on power or is it also NOW have a miss or stalls or ect. I would start with a compression check to make sure your not wasting your time looking at every little thing at first...then look at every little thing.
     

  5. GordonC
    Joined: Mar 6, 2006
    Posts: 3,157

    GordonC
    ALLIANCE MEMBER

    Come on guys Red is trying to help... Yes he needs to learn a bit more.

    97 is typically used in hot rod circles to describe a Stromberg 97 carb. The fellow above is running 2 of them.

    For the guy with the problem we need a bunch more info to help. Has the car always had this carb setup or is it a recent change? What air cleaners are you running? Is the motor stock? Do you know your fuel pressure? When was the last time the car had a complete tune up? Have you pulled the plugs to get a look at how its firing? Start checking into some of these things and I think that will help lead to whats going on.
     
  6. blowby
    Joined: Dec 27, 2012
    Posts: 8,661

    blowby
    Member
    from Nicasio Ca

    Release the parking brake. ;)

    Seriously, timing retards as points wear. Also check the vacuum brake in the crab.
     
    LOU WELLS and Bandit Billy like this.
  7. Now this whole "carb" and "crab" thing's got me confused. :confused:

    Had the car run properly for you before it started acting up? What work has been done to it between then and now?

    If you're not familiar with ignition and tune-up work, here's a bit of reading that should help get you started out on the right foot. ;)

    https://www.jalopyjournal.com/forum/threads/hot-rod-technical-library-basic-ignition-systems.983424/

    :rolleyes:
     
  8. Glenn Thoreson
    Joined: Aug 13, 2010
    Posts: 948

    Glenn Thoreson
    Member
    from SW Wyoming

    Sounds like a crapped out coil. Try another coil. These coils are known for pooping out. Any coil of the proper voltage will do for a test. I'll bet it fixes it. Let us know, please.
     
  9. worken2much
    Joined: Jan 11, 2009
    Posts: 67

    worken2much
    Member

    I grew up with carbs & point ignition. Having to nurse the car away from the stop light by riding the clutch was often a sign of needing to set or replace the points. Remember that adjusting the point gap affects timing. Point work first, then timing. After that, once fully up to operating temp, then carb fine tuning.

    Good luck,
    Worken2much
     
  10. flatjack
    Joined: Feb 13, 2007
    Posts: 975

    flatjack
    Member

    You really need to have the distributor checked out on a machine to see if it is timed properly and advancing properly. If that's good, carbs are next.
     
  11. christmas tree
    Joined: Dec 7, 2009
    Posts: 347

    christmas tree
    Member

    So hard to help from the recliner but I,m leaning towards the dist. advance and points. Agree with flatjack and several others.
     
  12. zzford
    Joined: May 5, 2005
    Posts: 1,823

    zzford
    Member

    Are you driving into a strong headwind?
     
  13. Hnstray
    Joined: Aug 23, 2009
    Posts: 12,355

    Hnstray
    ALLIANCE MEMBER
    from Quincy, IL

    wait.........how is poor performance not the standard for flatheads? :confused:

    Ray
     
    joel, Nailhead Jason, sunbeam and 4 others like this.
  14. christmas tree
    Joined: Dec 7, 2009
    Posts: 347

    christmas tree
    Member

    By todays standards my roadster is not fast but it is quick enough to make you pay attention. 313 cu in. Crane cam and all the other goodies I could afford. 16810366_1710180402341669_541649446_o.jpg
     
  15. beezil007
    Joined: Sep 8, 2012
    Posts: 12

    beezil007
    Member

    Thank you everyone there is some good advice there, I am in New Zealand and purchased the car in the current set up. I had issue originally with no spark had a guy install new coil and points here but not sure it is all set up right. I have had the accelerator pumps in both carbs replaced. It runs a mooneyes fuel pressure gauge in the fuel block which usually reads around 3 psi this has now dropped off to nothing??? Could this be my issue? I am running a electric fuel pump in-line under the car with an in-line filter I haven’t looked at this yet thanks again for any advice


    Sent from my iPhone using H.A.M.B.
     
  16. No fuel will affect performance.

    Now that you have discovered what the gauge says, verify that it is telling the truth and if it is, do what you need to do to get fuel flowing again.

    Report back with results. Maybe that's all it is.
     
    WTF really likes this.
  17. southcross2631
    Joined: Jan 20, 2013
    Posts: 4,413

    southcross2631
    Member

    I had a 50 Ford once that lost some power and had a slight miss. Pulled the plugs and shined a light into the cylinders and found a hole in the top of a piston. Drove it like that for about a month before I fixed it. Just low on power.
     
  18. Kiwi 4d
    Joined: Sep 16, 2006
    Posts: 3,579

    Kiwi 4d
    ALLIANCE MEMBER

    I see you belong to gear jammers . Does that mean you are in the Kapiti area?
     
  19. When was the last time you put a set of points in it? Its just a question. First thing I ever check is the points then I start looking for the bad things that could be wrong.
     
  20. If your planning on digging around with the distributor, this is a good opportunity to put a pertronix module in there. Just a thought.
     
  21. beezil007
    Joined: Sep 8, 2012
    Posts: 12

    beezil007
    Member

    Sorry forgot to add I am running a Holley fuel regulator also the other day I noticed this was making a vibrating sound could this be an issue?


    Sent from my iPhone using H.A.M.B.
     
  22. sunbeam
    Joined: Oct 22, 2010
    Posts: 6,220

    sunbeam
    Member

    Zero fuel pressure can be a problem. Check the easy stuff first fuel filter.
     
  23. Do that and will never run properly again...Stay away from Petronics
     
  24. Hmm... Not challenging your experience with Pertronix, but I have ran one in an OT vehicle for almost 20 years with an MSD added and never had an issue. I also have an FSI Distributor (which utilize a pertronix module)on my dizzy in my banger Model A that works fine. Bubba's also uses them. The do require proper voltage to work right though. Not interested in a debate on these (several threads for that already), just tossing out an option for the original poster based on my personal experience.
     
    sunbeam and Hnstray like this.
  25. Glenn Thoreson
    Joined: Aug 13, 2010
    Posts: 948

    Glenn Thoreson
    Member
    from SW Wyoming

    It seems you have found your problem. You could have partially plugged fuel filters and/or lines. Change filters. Blow the lines out with compressed air. Disconnect the line from the tank first, though. You don't want to blow junk back into the tank. Check pump pressure and flow at the pump. Bad regulator? If in doubt, replace it. Any flexible lines or hoses? Check them for internal swelling and/or air leaks if on the suction side. If you have spark and adequate fuel flow, it should be good to go.
     
  26. ........and if that doesn't restore your 3psi fuel pressure, swap out that "Buzzing" fuel regulator for the non-buzzing model. Or maybe a simple adjustment of the regulator [if it's an adjustable one] will restore pressure.
     

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