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I've got a manual for the f series motor but it does not give the torque for the motor to the chassis. Does anyone have those spec or know where I could look? thanks

No need to torque the mounting bolts, just make sure that they are good and tight.

thanks

Rivets said:

No need to torque the mounting bolts, just make sure that they are good and tight.

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I don't agree with this. Every bolt and nut should be torqued. Do I do it, HELL NO. If you don't have toque specs you will need to look them up. There is a chart that gives these specs by bolt type and size. I keep one of these charts by my tool box all the time and you can find this chart on line.

I torqued the bolts to about 40 ft lbs which is way too much for an aluminum motor. I'm planning on backing the bolts off tomorrow. I hope it will be okay to back off the torque.

thanks

godavid said:

I torqued the bolts to about 40 ft lbs which is way too much for an aluminum motor. I'm planning on backing the bolts off tomorrow. I hope it will be okay to back off the torque.

thanks

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The reason to torque a bolt is to stretch it. That is the reason you need to know the size and type. Aluminum has nothing to do with it. It would be a good idea to have flat washers under the heads. 40 ft lbs would all depend on the bolt size and type??? If you give me that information I can give you the proper torque.

reynoldston said:

The reason to torque a bolt is to stretch it. That is the reason you need to know the size and type. Aluminum has nothing to do with it. It would be a good idea to have flat washers under the heads. 40 ft lbs would all depend on the bolt size and type??? If you give me that information I can give you the proper torque.

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The bolt is 1/4" coarse threads length not including the bolt head is 3-1 1/2" and 1-2" thanks tpi is 20

thanks

godavid said:

The bolt is 1/4" coarse threads length not including the bolt head is 3-1 1/2" and 1-2" thanks tpi is 20

thanks

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1/4-20 bolt, Grade 2, 70 IN. Lbs., Grade 5, 115 IN. Lbs. Grade 8, 165 IN. Lbs. We are talking inch lbs. not foot lbs. Don't know how you torqued a 1/4 20 bolt to 40 FT. Lbs. without snapping it?? Are you sure of that size because it seem small to me.

Lawnboy manual specifies a product (under Lawnboy name) which is basically Locktite. They call for the lighter version for above deck fasteners, and the more robust product for under deck fasteners.

I got a picture of that F series engine on you tube. The mounting bolts look to be 3/8 in size. That bolt call for 35 FT. Lbs. so 40 FT. Lbs. wouldn't be a bad number. Just back off on them a little. There is a lot of Lawn boy owners on this forum so dose someone know what size engine mounting bolts they use on this engine?

Phototone said:

Lawnboy manual specifies a product (under Lawnboy name) which is basically Locktite. They call for the lighter version for above deck fasteners, and the more robust product for under deck fasteners.

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I don't care how much Loctite you use, 40 FT. Lbs. is too much for a 1/4-20 bolt. If they do use 1/4-20 bolt, yes use Loctite.

reynoldston said:

I got a picture of that F series engine on you tube. The mounting bolts look to be 3/8 in size. That bolt call for 35 FT. Lbs. so 40 FT. Lbs. wouldn't be a bad number. Just back off on them a little. There is a lot of Lawn boy owners on this forum so dose someone know what size engine mounting bolts they use on this engine?

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I measured the bolts and they were 1/4 20 I back them off So I don't know why them did not strip. I re-tighten them but not as tight as before.

thanks

You just made me wonder so I took a 1/4-20 bolt grade 5 to see what a top torque before it wouldn't take any more torque. Didn't have a grade 8 bolt to try. The very top was 13 ft. lbs. You must have a bad torque wrench. Not possible to toque a 1/4-20 bolt to 40 ft. lbs. All my charts are in in. lbs. for a bolt that small. Am I missing something here??? if so let me know. It wouldn't be the first time I was wrong :confused2:

I just measured the diameter of the mount holes on an F-series deck: 3/8".

I knew 1/4" sounded way too small for mounting a motor to a deck. :laughing:

Two-Stroke said:

I just measured the diameter of the mount holes on an F-series deck: 3/8".

I knew 1/4" sounded way too small for mounting a motor to a deck. :laughing:

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Thanks this is what I was trying to say.