a hard running 3.5 outboard

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a hard running 3.5 outboard

Postby low rollin ray » Thu Oct 13, 2011 11:47 pm

i think i have the oldest 3.5 outboard you can get short skeg model small id nos i bought it on ebay well upon start up it revved till the con rod bush turned into pieces a new rod was bought all good upon dismantling i found the piston pin to be facing the exhaust port which i changed to facing upwards so it could not drop into the exhaust port new gaskets and tried again well it continues to run flat out it had a black carb i changed it to a gold carb still the same reving flat out it has all new lines a new fuel tank so you would think all was well the only way i can control it is to choke the carb with my finger and use the little breather hole on the bottom of the carb and it is controlled bearing in mind that the carb hole is basically shut then i found the carb housing the front plate was cracked around the the allen bolt so my my qu is ihave aquired a new front housing 13mm crank new bearings all new is it compatible with the early motor if you replace the crank and front housing or is the stroke different also both motors i have dont seem to have a head shim is this my problem it seems like a screamer wants to go hard but no throttle response im dumbfounded and i have to race a friend shortly who has a two stroke china job will he whoop my ass i really want to kick his thanks any replys gratefully accepted
low rollin ray
 
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Postby stagefright » Mon Jan 16, 2012 5:31 pm

The carburetor has A barrel in it to choke off the flow of air and fuel ya know! Nothing runs flat out if the carb or exhaust throttle is closed. If ya have an air leak in the crankcase it will run lean and possibly rev weird. But I think you gotta know how to run an engine.
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Re: a hard running 3.5 outboard

Postby low rollin ray » Sat Jul 13, 2013 10:16 pm

hey ya stage fright , not backwards in comin forwards, its pretty easy just to put your finger over the carby rather than use the remote , and yeah ive been playing with gas engines for a long time and while not a genius am not completely backwards bro! ya know
low rollin ray
 
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Re: a hard running 3.5 outboard

Postby Chief » Wed Oct 02, 2013 9:26 am

Hay Low rollin, if you are still out there and have not had any answers, I have some for you. All the 3.5 engines have the same bore and stroke. Bore 0.65 Stroke 0.64. Head clearance should be .018
The new front housing should match the 13mm crankshaft along with the 13mm rear bearing. You should check the measurements of the crank pin and rod. Should be the same. Piston pin should face away from exhaust port and have a Teflon pad. Check all gaskets, screw threads make sure everything is tight. Need more info? Just ask. Hope this helps if you still need it.
Chief
 
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Re: a hard running 3.5 outboard

Postby SteveM » Wed Oct 02, 2013 9:42 am

The K&B outboards use a reverse rotation crankshaft. When using an electric starter, you must switch the starter leads so that you spin the starter cone clockwise.
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Re: a hard running 3.5 outboard

Postby low rollin ray » Thu Oct 03, 2013 1:15 am

chief and steve m , thanks for your input, the boat in qustion im thinking is a hughey hull, foam filled, is that normal for a hughey it seems awfully heavy, , an ebay job, nice paint job,old 3.5 a screamer , hit the water and died , conclusion to lean, run fatter, plug burnt out , end of race day. any info on hughey hulls more than welcome i have the hydro hull circa 78/ 82 any photos apprieciated, adjustable engine mount all balsa would that be correct, anyway any info much wellcom.
low rollin ray
 
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Re: a hard running 3.5 outboard

Postby Chief » Tue Oct 15, 2013 7:05 pm

Hay Ray, I never ran the hughey boats, I ran OPC Tunnel A Mod. I removed the carb. installed a spray bar setup and a exhaust throttle. Ran 60% Nitro fuel and it was a real screamer. I will try a take some pictures for you so you can see the setup. If you have a e-mail address that would be easier to send them.
Chief
 
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Re: a hard running 3.5 outboard

Postby Chief » Wed Oct 16, 2013 2:22 pm

I toke some pictures with my Spam Word and will try to upload them. Hope it's good. We'll it won't take 2 pics. I'll try multi tries.
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Re: a hard running 3.5 outboard

Postby Chief » Wed Oct 16, 2013 2:25 pm

#1 pic. Oh we'll, it won't take it. You will have to send me your email address.
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Re: a hard running 3.5 outboard

Postby low rollin ray » Wed Oct 16, 2013 10:26 pm

hi chief thanks for the interest im a bit reluctant to put my email out there as im woried ill get spammed to death unless there is some other way to contact you if not thanks for taking the time. ray.
low rollin ray
 
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Re: a hard running 3.5 outboard

Postby Chief » Thu Oct 17, 2013 11:29 am

Ok Ray, send me an e-mail here. nhallinan@dc.rr.com I'll get back to you.
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