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Discussion Starter · #1 ·
Happy New Year ,all Dooers

I fired up my 7500 this morning ,let it warm for a few and then set out for what would have been a good hour of that familiar sound.Then about 10 minutes into my ride,all forward motion stopped. I had put in a brand new set of plugs before leaving and it was running amazing.(I know ,thats what everybody says right before the motor blows).It made no noises of any kind,I was travelling at 50% or less throttle with an occasional blip of the throttle.Then out of the blue it just came to a rolling stop with the engine turning all the way to stop but not running.No bang, no tick tick tick, no smoke, nothing. After looking under the hood for all the obvious causes of death and finding nothing visually,I went to the pull start.The engine,still warm rolled over but stiff.I walked home and returned with the pick-up and loaded it. When I got home ,I pulled the rope again slowly and still very stiff (engine cold now).My first guess is it spun a crank bearing .I had this engine type 354 rebuilt to .040 oversize 3 years ago and have not had any hiccups with the rebuild since the engine was installed.

Anybody have an idea or it happened to me stories.A little pre autopsy research never hurts.

Thanks , Lucky
 

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First of all, sorry to hear about the demise of your 354
Start with the obvious, you changed the plugs, were the new ones both correct heat range? Are you positive your last batch of premix was mixed correctly? Any jetting changes? Pull the exhaust pipes and shine a flashlight in the exhaust ports and see what the exposed part of the piston looks like. Hopefully the damage is limited to the top end, but you probably won't know until you tear it apart...sucks to be looking at a rebuild again.
 

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sorry to tell ya but those are the EXACT symptoms i have had everytime i had to rebuild the top end on my 354. i would be running and all of a sudden it was as if someone just shut the key off. mine turned out to be dirty needle valves. i had taken the carbs apart several times previously but never took those out
 

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What color were the spark plugs when you removed them after the stall.If greyish white,your in trouble (too poor).Were the carbs cleaned before it came out, varnish build up in the summer. Old gas.Engine rebuild was 3 years ago,its prooven,no problem there.
 

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Thanks for the input guys, Well the jetting is the same ,I used fuel STABIL in the spring,and added some fresh gas mix.I had a set of BR9's in it and changed them out with BR10EYS.I'm not sure who ,but last year someone suggested this number, but whatever the reason,it sounded like a good idea at the time.Could it be, that I am a victim of my own creation ? It would appear so.I hate when that happens.So considering it was built to .040 over ,what's the next rebuild stage? Change out the sleeves or change cylinders .(Are 454 cylinders my next step perhaps?)

Lucky
 

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Discussion Starter · #6 ·
Hey guys,

I hav'nt had a chance to perform the autopsy yet .After the the engine quit ,I brought the sled home and decided to blow the snow out of the driveway.So I fired up the snowblower and 5 minutes into it ,the amount of snow being thrown was minimal.Upon further inspection I discovered that the auger was not turning.Seriously, 2 breakdowns in one hour.

So I proceded to tear apart the worm drive and yes, the worm gear (brass) and the worm drive shaft were both horribly disfigured.So I ordered $170. worth of parts and am waiting for delivery. Somehow I think the blizzard rebuild will be way more involved.

Lucky
 
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