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1973 Broadmoor engine fitment questions


rickpilgrim

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We picked up 2 broadmoors from a member, one (738)has a transplanted 10hp Briggs in it that needs carb work but runs ok, the other one (727)was for parts but .....

Can a 12 hp Briggs from a Sun Runner be bolted in and still keep the stock 727 hood or am I better off finding another 10hp that barely fits?

Thanks Everyone!

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I don't believe there is much difference between 10 and 12 hp Briggs. I'm getting a Simplicity 5010 with a 12hp Briggs on it and a friend of mine has a 12hp on his 610 Allis so you should have no problems fitting a 12hp in a 727.

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I thik the 8 and 10 hp are the same size blok and the 11 & 12hp are a bigger block. I've seen the 11 & 12's used but there may be some mods to the tractor to make fit. Could be the spark plug sticks out too far and the grills have to be notched for it. Dont remember right off, just trying to remember the oes that have come through my shop over the years.

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If it is a model 286XXX IC engine, you will have a problem. The blower housing rubs up against the fuel tank. I did one and had elongate mounting holes.

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Did you have to elongate the motor mounting holes or the cowling holes? The gas tank on mine sits in the cowl with the battery behind it. As the GT360 battery has about 1/2" of front/back movement I could always move the tank and battery back and oval the fuel fill hole in the hood or am I thinking wrong here. BTW the sun runner 12hp is an I/C.

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The sunrunner 12 hp motor should bolt in only thing i noticed on the 12 hp motors is they are longer on the head side so you might have to pull grill and hood a little forward

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I did the holes in the frame with a rat tail file. And then I used 5/16" bolts to help it also. Then I trsnfered it to a 5010 and then had to carve out hood and air cleaner housing along with elongating monuting holes. Overall the used 12 HP lasted about thirteen years and then I was given a like new spec 10 HP engine and I installed it. I keep the 5010 as it has an equal or better finish then the 44, 48, 54 and 60 inch decks. And it'd narrow enough that I can ride the curb and cut around city trees.dOd

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I did the holes in the frame with a rat tail file. And then I used 5/16" bolts to help it also. Then I trsnfered it to a 5010 and then had to carve out hood and air cleaner housing along with elongating monuting holes. Overall the used 12 HP lasted about thirteen years and then I was given a like new spec 10 HP engine and I installed it. I keep the 5010 as it has an equal or better finish then the 44, 48, 54 and 60 inch decks. And it'd narrow enough that I can ride the curb and cut around city trees.dOd

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