Author Topic: Carb quetion  (Read 1925 times)

homermjs2008

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Carb quetion
« on: April 24, 2014, 04:22:06 PM »
Ok so here's the deal I have a Fl350 and the guy I got it from said it was race ready. (WRONG) So we bought the odyssey about 12 years ago got it home started it and it had a vibration that there's no describing. Not only that when we would put it in gear parts of the clutch would go flying. Crazy right? It gets better. So we found out that the harmonic balancer was flipped. and we replaced the clutch. Got it running and took it out. 30 minutes of riding. blew the top end. Bore it, fix it take it out and same thing in the same spot. So this time I completely rebuild the motor and also came to realize that the left crankcase tube was left open. FYI has a gravity fed tank. So I plug the vent and get it running. Take it out get about oooh 45 minutes out of it and blew the top end. All three times on the exhaust side. Running lean I know. so then I let it sit for 8 years and now I'm back to rebuilding it and doing all kinds of research along the way.
So here's my question. It has a 38mm Mikuni carb with a 52 pilot and a 135 main. to big and to small. YUP. So I'm not looking for huge power I just want to ride the dame thing. What shout I do. Stick with the carb and hopefully someone on here could tell me what the right jets might be or should I bite the bullet and go back to a smaller carb? The carb I have is a Mikuni T38 85A

hoodlum

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Re: Carb quetion
« Reply #1 on: April 24, 2014, 07:16:49 PM »
When you say "blew the top end", what are you referring too? Did the engine seize or did it melt the piston? It could be the result of not enough clearance on the exhaust bridge....
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homermjs2008

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Re: Carb quetion
« Reply #2 on: April 24, 2014, 08:23:17 PM »
Melted the piston on exhaust side. Bridge was releaved.

nevadanotch

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Re: Carb quetion
« Reply #3 on: April 24, 2014, 08:35:32 PM »
Well if it helps any, I am running a Mikuni TM38 and I have a 420 main in it with a modified air box and a DG pipe and FMF Quiet Core II.
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homermjs2008

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Re: Carb quetion
« Reply #4 on: April 24, 2014, 08:52:48 PM »
Is the tank gravity fed and how long have you been running?
I'm just concerned because I'm roughly $550 into the rebuild at this point and want to make sure I get it right.

nevadanotch

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Re: Carb quetion
« Reply #5 on: April 24, 2014, 11:26:00 PM »
DO NOT GRAVITY FEED!

Use the fuel pump.  You are starving the motor for fuel.

Also note that I am running at approximately 5000 feet in elevation so you may need to go up even higher in jetting.
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homermjs2008

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Re: Carb quetion
« Reply #6 on: April 25, 2014, 04:49:47 AM »
Ok thanks. I'll have to see how to run a pump off the tank I have. It's currently a gravity fed.

nevadanotch

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Re: Carb quetion
« Reply #7 on: April 25, 2014, 07:49:55 AM »
To do the gravity feed, you will need to put a fuel return line into the neck of your existing tank or you can change the fuel cut off valve to a 1.8.
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homermjs2008

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Re: Carb quetion
« Reply #8 on: April 27, 2014, 07:36:14 PM »
Well I decided to bite the bullet and go back to the 32mm mikuni carb. I'm going back to stock as much as possible. The only thing that's not is the gas tank and I'm going to be running a pump off it. I have to modify it to add a return line. I figured that I shouldn't run the 38mm because of not having after market on it and really didn't want to take the chance of screwing up the motor again. It's so stupid it almost makes me sick on how the guy I got it from jacked it up so much.