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Thread: Slow/Labored Cranking

  1. #1
    Senior Member jwebb's Avatar
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    Slow/Labored Cranking

    Cranking is slow/labored for several seconds, then speeds up, could a poor ground be the issue or do I have a starter issue?
    MK4 #9121 - Complete kit - Stroked 351, T5x, 3.55 Rear End, 3-Link - Pickup 6/17/17, 1st start 12/2/17, Go-Kart 12/9/17, Road Worthy 4/27/18

  2. #2
    Senior Member seagull81's Avatar
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    Get a short battery cable and run it from one of the starter bolts to the frame. If it is a ground issue that will fix it.
    Steve
    Texas Cobra Club-Austin
    July 2009 FFCars Picture of the Month
    FFR3542K, 347 C.I., EFI, T-5, 3-Link, Miata Front Sway Bar, Red with White Stripes

  3. #3
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    Defiantly a power supply issue as you are having problems delivering enough power to support the motors inrush requirements (the reason for the slow starter spool up) Depending on the motor, starter, cable length, and gauge size you may have a issue with line losses due to a under sized cable. You can see if the cable is hot after rolling the motor for 5 seconds. I’m running a trunk battery and was forced to use much larger cable due to calculated line losses based on my starter requirements. I got my cable from summit racing and have a custom grounding strap. You can also check the ground cable to make sure it has a good connection. It may also benificial to make sure the cable ends are soldered to the lugs otherwise corossion will be a problem. They sell what is called battery terminal solder plugs that you put in the terminal and then heat it will pushing the cable into it and when it melts you let the assembly cool and shrink tube the exposed section and your good to go.

  4. #4
    Senior Member phileas_fogg's Avatar
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    Quote Originally Posted by GFX2043mtu View Post
    Defiantly a power supply issue as you are having problems delivering enough power to support the motors inrush requirements (the reason for the slow starter spool up) Depending on the motor, starter, cable length, and gauge size you may have a issue with line losses due to a under sized cable. You can see if the cable is hot after rolling the motor for 5 seconds. I’m running a trunk battery and was forced to use much larger cable due to calculated line losses based on my starter requirements. I got my cable from summit racing and have a custom grounding strap. You can also check the ground cable to make sure it has a good connection. It may also benificial to make sure the cable ends are soldered to the lugs otherwise corossion will be a problem. They sell what is called battery terminal solder plugs that you put in the terminal and then heat it will pushing the cable into it and when it melts you let the assembly cool and shrink tube the exposed section and your good to go.
    I used those solder lugs (https://theelectricaldepot.com/index...er+lug&x=0&y=0) to trim the F5-provided battery cables to the length I needed. They're super easy to install; just be sure that when you insert the cable into the molten solder you go relatively slowly so that you don't end up with an air pocket in your solder joint.

    Cheers,


    John
    MK IV Roadster #8631
    Ford 302, Holley Terminator EFI, T5z, 3.55 Rear End, IRS, 17” Halibrand Replicas (9” front, 10.5” rear), Nitto 555 G2’s (275/40ZR17 front, 315/35ZR17 rear), Fast Freddie’s Power Steering, F5 Wilwood Brakes, FFMetal’s Firewall Forward, Forte’s Hydraulic Clutch & Throttle Linkage
    https://www.ffcars.com/threads/phile.../#post-4776313

  5. #5
    Not a waxer Jeff Kleiner's Avatar
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    FFR supplied #4 cables with a trunk mounted battery by chance? If so they are marginal at best as many others have discovered. Replacing EVERYTHING (any system is only as good as the weakest link) with #2 cables generally solves it.

    Jeff

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    Senior Member jwebb's Avatar
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    Using FFR #4 cable with trunk battery, will replace cable and add 2nd ground strap! Thanks all!
    MK4 #9121 - Complete kit - Stroked 351, T5x, 3.55 Rear End, 3-Link - Pickup 6/17/17, 1st start 12/2/17, Go-Kart 12/9/17, Road Worthy 4/27/18

  7. #7
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    Another cause of your issue, can be too much initial timing. I suspect the previous advise given is spot on.
    20th Anniversary Mk IV, A50XS Coyote, TKO 600, Trunk Drop Box, Trunk Battery Box, Cubby Hole, Seat Heaters, Radiator hanger and shroud.

  8. #8
    Waiting for my 65 Coupe nskaats's Avatar
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    Make sure your chassis grounds have all the powder coat cleaned off of them. It also never hurts to add an additional ground strap to the chassis from the engine. It's impossible to have too much ground.

    As Railroad mentioned backing off initial timing helps as well. I usually only have a few degrees in them while cranking.
    --Nick Skaats--
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    Mark Eaton's Avatar
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    I am puzzled that FFR would recommend a trunk mount battery and yet supply a battery cable which is insufficient. I am mounting my battery in the trunk just like in the build manual, although, a little different position. After reading this thread I am ordering a #2 gauge battery cable from Summit. Do I also need different grounding straps? Here is what I am using (came with my complete kit). And I did grind the powder coating away from the chassis.

    Battery ground:



    and engine ground strap:



    Do I also need a starter ground cable? And can I use the FFR #2 cable for that? The one that is otherwise useless to me...

    Thanks,

    Mark
    MK4 #9130 , complete kit, arrived 8/10/2017, Street Legal 2/14/2020.
    DART SHP 347, EFI, TKO600, IRS
    http://thefactoryfiveforum.com/showt...n-Build-Thread

  10. #10
    Senior Member CraigS's Avatar
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    Quote Originally Posted by Mark Eaton;308338
    [IMG
    http://thefactoryfiveforum.com/attachment.php?attachmentid=78879&d=1515464116[/IMG]

    Do I also need a starter ground cable? And can I use the FFR #2 cable for that? The one that is otherwise useless to me...

    Mark
    I would move what you have to the rear of the engine mount pedestal and then run it to one of the starter mount bolts.
    FFR MkII, 408W, Tremec TKO 500, 2015 IRS, DA QA1s, Forte front bar, APE hardtop.

  11. #11
    Not a waxer Jeff Kleiner's Avatar
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    Quote Originally Posted by Mark Eaton View Post
    Do I also need a starter ground cable? And can I use the FFR #2 cable for that?
    Mark, The FFR cables are #4, not #2. I don't actually know what the supplied braided strap is equivalent to. My recommendation; #2 from battery + to solenoid, #2 from battery - to chassis, braided strap from block or starter bolt to chassis as Craig said. If you have a battery cutoff switch you'd go #2 from battery + to one side of the switch and another #2 from the other side of the switch to solenoid.

    Jeff

  12. #12

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    Jeff,

    Is the FFR #4 cable consistently a problem with long cable runs, or does it seem to vary based on other components in the system (battery, heater, fuel pump, etc.)? I have a front-mounted battery, but the cable runs to a master cutoff left of the steering wheel, then over to the starter - which is about the same distance as a trunk-mount battery. I'm inclined to see how it works and change to #2 only if I have a problem. Any advice would be appreciated!

  13. #13
    Senior Member rich grsc's Avatar
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    Quote Originally Posted by Jacob McCrea View Post
    Jeff,

    Is the FFR #4 cable consistently a problem with long cable runs, or does it seem to vary based on other components in the system (battery, heater, fuel pump, etc.)? I have a front-mounted battery, but the cable runs to a master cutoff left of the steering wheel, then over to the starter - which is about the same distance as a trunk-mount battery. I'm inclined to see how it works and change to #2 only if I have a problem. Any advice would be appreciated!
    In my experience, it's a component issue. My old car had the battery in the trunk, and I never had a starting problem once I bought a new mini-starter. I'm using the FFR cables in my newest build now, but the battery on this one is on the top of the passenger foot box. A good battery and a good starter, and the supplied cables are fine.

  14. #14
    Mark Eaton's Avatar
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    Thanks guys!
    MK4 #9130 , complete kit, arrived 8/10/2017, Street Legal 2/14/2020.
    DART SHP 347, EFI, TKO600, IRS
    http://thefactoryfiveforum.com/showt...n-Build-Thread

  15. #15
    Not a waxer Jeff Kleiner's Avatar
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    Rich and I usually agree but on this one our experiences and opinions differ. First built my own car with trunk battery, new starter and the #4 cables. No issues until hot days with some heat soak. Changing to #2 solved it. Many others report the same. I've built cars with a front mount battery and short #4 cables which have no starting problems but every car that I've built since with a rear mount battery gets #2 cables. As Oben says; "YMMV"

    Jeff

  16. #16

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    Rich and Jeff, thanks for our input. I'm going to try the #4 cables for now since they're mostly installed, and I'll get a new mini-starter. I'll report what I find here whenever the car runs (hopefully by summer if all goes as planned).

  17. #17
    Senior Member rich grsc's Avatar
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    My statement applies to what worked for me. I guess I was just luckier than some.
    I know Jeff can't admit he's wrong.

  18. #18
    Not a waxer Jeff Kleiner's Avatar
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    Quote Originally Posted by rich grsc View Post
    My statement applies to what worked for me. I guess I was just luckier than some.
    I know Jeff can't admit he's wrong.
    Hey now Rich! I'm wrong all the time...ask my wife, she'll tell ya'

    Jeff

  19. #19
    Senior Member rich grsc's Avatar
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    Had a girlfriend like that.

  20. #20
    Senior Member jwebb's Avatar
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    Initial timing was fine, turned out to be a bad ground, works perfectly now!!

    Thanks!
    MK4 #9121 - Complete kit - Stroked 351, T5x, 3.55 Rear End, 3-Link - Pickup 6/17/17, 1st start 12/2/17, Go-Kart 12/9/17, Road Worthy 4/27/18

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