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Questions about motor mounts

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DexterLB

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Until now, I haven't made standard motor mounts, so I'm a complete newbie in this sphere.

I've some questions:
1: I see that engine hooks have a little "hook" on the back. What is it used for? Can it hold the engine from gowing upwards, or I also need an engine block ring?

2: Is the 18mm A and B motor length really 70mm!? Bulgarian A and B motors used to be 50mm, and C motors - 60mm.
 

jflis

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  1. That's really just to mount and stabalize the engine hook. While I have seen many people rely on that end of the hook to keep the motor from moving forward, I wouldn't recommend it. You should still have an engine block in place as the kick at ignition will make for a great deal of stress and can push the hook forward quite easily.
  2. Yep, they are really 70mm long (2.75") :)

Hope this helps!
jim
 

redsox15

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I have used the hook on the back to hold the motor in. What i do is put a slit in the mmt tube then put the hook in that then (like jim said) put a stop ring above that.

Matt
 

DexterLB

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  1. That's really just to mount and stabalize the engine hook. While I have seen many people rely on that end of the hook to keep the motor from moving forward, I wouldn't recommend it. You should still have an engine block in place as the kick at ignition will make for a great deal of stress and can push the hook forward quite easily.
I have used the hook on the back to hold the motor in. What i do is put a slit in the mmt tube then put the hook in that then (like jim said) put a stop ring above that.

Matt
Ok, that's what I'll do. Ah, and one more thing - which is the best way to fix the block-ring? Will LOCTITE do the job?

Yep, they are really 70mm long (2.75")
o_O well I don't think they're gonna renew the production of bulgarian motors... so I'll put the engine block at 70mm.
 
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mjennings

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If you mean loctite super glue yes that will work but so will plain old white or yellow glue. Also with the Bulgarian motors being shorter, if they go back into production you can always cut a spent motor down and use it as a spacer. We do that all the time with the 24 mm D's and E's.
 

DexterLB

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Thank you! Now I can make my motor mount ;)
 
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