K750 Fuel Problem

tim4

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I have a husqvarna k750 which has new cylinder, piston and rings and new crank seals. It will run if you squirt fuel in the sparkplug hole but it does not seem to suck the fuel up from the tank. The fuel filter is new and fuel is getting to the carb when I take the line of f fuel runs out of the fuel line. The diaphram is good in the carburetor and when you press it down carb cleaner goes through the needle and seat fine. There is a hose that is fine which goes to 2 connections on the carburetor. I think that is for the fuel pump system.
 

Tiger Small Engine

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I have a husqvarna k750 which has new cylinder, piston and rings and new crank seals. It will run if you squirt fuel in the sparkplug hole but it does not seem to suck the fuel up from the tank. The fuel filter is new and fuel is getting to the carb when I take the line of f fuel runs out of the fuel line. The diaphram is good in the carburetor and when you press it down carb cleaner goes through the needle and seat fine. There is a hose that is fine which goes to 2 connections on the carburetor. I think that is for the fuel pump system.
If you are getting good, steady fuel flow to carburetor, then the carburetor needs attention and be cleaned.
 

tim4

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I think it will work now sinced I cleaned the fuel pump section again
 

tim4

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I got it running but how can I get to the adjustment screws after I put the air cleaner assembly in there is no hole to get to the mixture screws.
 

tim4

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I found out there is a small piece that slides off which has a opening to get to the adjustments. On the replacement cylinder I bought the hole that the vibration spring screw goes in is not tapped. It is a 7.100 metric tap sice. Is that a common size or is it special size.
 

RevB

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I found out there is a small piece that slides off which has a opening to get to the adjustments. On the replacement cylinder I bought the hole that the vibration spring screw goes in is not tapped. It is a 7.100 metric tap sice. Is that a common size or is it special size.
There's a large range of metric threads. Industrial standards define 1st, 2nd and even 3rd choice diameters in order to rationalise and reduce necessary stocks as far as reasonably possible. M7 is a 2nd choice size, so not common. That would be .2755 in. 35/128". You sure it takes an over 1/4" bolt?


Where is this located?
 

bentrim

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If memory serves me right that should be a self tapping screw.
 

tim4

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I figured that but the screw was going in too hard and I was afraid of braking it off.
 

StarTech

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Doesn't look like a Self tapper. Now if the screw is tri-lobular then it is a self tapper.

With the measurement being 7.1 mm it more likely 9/32-32 screw but this why you use thread gauges so you know if metric or not.

1746981653796.png
 

RevB

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There's a large range of metric threads. Industrial standards define 1st, 2nd and even 3rd choice diameters in order to rationalise and reduce necessary stocks as far as reasonably possible. M7 is a 2nd choice size, so not common. That would be .2755 in. 35/128". You sure it takes an over 1/4" bolt?

Doesn't look like a Self tapper. Now if the screw is tri-lobular then it is a self tapper.

With the measurement being 7.1 mm it more likely 9/32-32 screw but this why you use thread gauges so you know if metric or not.

View attachment 70917
That's a self tapper all right.
 
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