welding engine mount brackets

Discussion in 'HardCore Corner' started by john_d, Feb 28, 2009.

  1. john_d

    john_d

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    I'm planning on moving the motor mount brackets for a new engine.
    .
    Mechanics in my part of the world are not at all confident about welding the new motor mount brackets on the chassis. They all talk of stress fractures on the welds. They also claim that if the mounts are not in the correct position engine vibrations etc. could ensue.

    Also, is MIG welding suitable for this purpose?

    How does one go about doing all this properly? I couldn't find too much info on the internet.

    What's the score on the above, guys? Is it really all that complicated?
     
  2. usmcruiser

    usmcruiser

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    Scab plates + good penetration with a MIG = no problems IMO.
     
  3. mrqtipp

    mrqtipp

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    Exactly what usmcruiser said. Turn the heat up and burn them in..

    ****ty first weld the the auto tint helmet I was using no workieee. I later went over and burned them in the heat up...

    062.JPG

    engine on the ground and drive train

    063.JPG

    setting engine and drive train between frame rails/scab plates
    062.JPG 063.JPG 066.JPG
     
    Last edited: Feb 28, 2009
  4. mrqtipp

    mrqtipp

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    Decide where you are going to place your engine within the frame rails and weld in scab plates.

    I pushed my engine as far forward as possible to keep heat off the firewall and make room for lots of drive train. Engine also sits very high which allowed me to tuck the drivetrain close the body and allowed max oil pan clearance.

    I used GM motor mounts. I cut a piece of plate and drilled wholes to the pattern of the motor mount. Bolted plate to the motor mount and then placed engine in the exact area I wanted, then made a templete for the difference between the motor mount and the frame scab plate out of cardboard then cut some plates and burned them in.

    001.jpg

    I wouldnt worry about anything cracking..

    002.JPG
    001.jpg 002.JPG
     
  5. fyresq

    fyresq

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    I guess it would depend on what size welder you are using but MIG is fine. Just burned my scab plates last night.....haven't downloaded any pics yet but it came out pretty good. As long as you keep decent bushings/donuts etc. in there, you shouldn't have too much of a problem with vibration and a good weld job should never crack. The cruiser frames have decent metal and are pretty stout. If you are worried, do multiple passes.
     
  6. john_d

    john_d

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    I'm a real novice at this. Anywhere I could get detailed instructions for this sort of thing?
     
  7. bikersmurf

    bikersmurf

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    I weld but am not a welder. I did all the prep work including making some apx. 4"x6" scab plates for Downey mounts. Then paid $60 for a Nascar certified welder to come to my house and weld them in. He used a Truck mounted "Stick" welder. It's been 12+ years with a 300 hp 350 chev and no signs of cracking. No problems with vibrations etc. If in doubt pay a WELDER... a lot cheaper than being towed home. imo.
    The guy I used was done in less than an hour. If you can't find a WELDER then??? I think I'd still use STICK it's more forgiving of contamination and is easier to lay a decent bead (unless you have a REALLY good MIG). Best of luck.

    One thing I would do differently would be to position the engine 1/2" further back... then my FJ 40 drive-shafts would both be the same length.

    The engine centerline should be 12" from the frame rail don't recall which side at the moment... but it should be obvious. (PM me if you'd like me to go measure)

    Advance Adaptors used to have a conversion manual.
     
  8. fyresq

    fyresq

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    Like Bikersmurf I welded but wasn't a welder so when I started working on the cruiser, bumpers, frames, rollcages, etc., I went to the local college and signed up for welding and metallurgy classes. A few years and a few certs later I feel pretty good about my welding strength. I will also agree that if you don't have a decent MIG welder, the stick may be the better way to go BUT the MIG IMHO is much easier to use than the stick and if you are using gas you get much less porosity, slag, and barely need to clean your welds. If you know what to look for in the pooling of your welds the MIG is "point and shoot".

    If you haven't done much welding I would recommend a mobile welder.....but this may be the opportunity to educate yourself and aquire a new skill
     
  9. john_d

    john_d

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    I've read that arc welding is better in terms of strength than MIG.

    If I do use ARC welding what sort of stick or rod should I use and what should I look out for?

    Similarly what do I look out for if I use a MIG welder in terms of size and wire type and quality?

    Thanks.
     
  10. usmcruiser

    usmcruiser

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    I suggest you go to your local "Career Development Center" and take a Welding class. Plain and simple.
     
  11. fyresq

    fyresq

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    If you are going to attempt to weld on your rig you should be able to answer these questions yourself. Like said above, you should either A. hook up with someone who can teach you how to weld or B. go find classes to learn or C. pay someone to do it for you
    Welding on your frame or integral parts of your rig like your rollcage isn't quite the same as busting out granpa's arc welder and booger welding a broken gate on the farm. It takes a good amount of time to learn to do correctly and more importantly if you "learned" to weld you could answer all your own questions posted. Welding isn't just "gluing" two pieces of metal together, it's knowing that you are getting good penetration, whether you're welding too hot or too cold, too fast or too slow, knowing what metals can be welded easily and which can't, how heat and cold effect the strength of metals, how to not cause warping, which wire, gas, or rods to use for different metals, and most importantly how not to set your eyeballs on fire :) Just take the time to learn and do it right!
     

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