Now the MAC 3516 Chainsaw problem

TheBishop

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After getting the old Homelite running last week, I got the carb rebuild kit in place for the MAC. It fires up and dies. After trying to restart, nothing. Waiting about 15 minutes, the MAC fires, revs up and dies.
I connected the new fuel lines going from the filter in the tank, to the fuel pump on the carb, out the carb to the primer bulb and back into the tank.
I looked at several online information spots about the proper fuel diagrams and they are mostly the same. I did find a guy that rebuilt a MAC 3516 and he ran the fuel lines from the tank to the primer bulb to the carb fuel pump and back into the tank, and said that was the proper way for the 3516.

Also, does anyone know the proper low and high setting for the 3516. I've started with 1" out on both and worked up to 2" out, but the best I get is cold startup, it fires revs up and dies. After that nothing until I wait 15 minutes.

I'm far from an expert at small engines. I know just enough to get by, but I have a lot of patience.

It's encouraging to get it to fire after sitting for at least 12 years, but like the Homelite, something is missing.

Any ideas on the low and high settings and the fuel routing?
 

EngineMan

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Waiting for 15 minutes tells me maybe the engine is flooded, low and high settings....one turn each from the bottom should get you going, then set them once you have it running.
 

TheBishop

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I took the carb apart again and adjusted the lift of the inlet needle so more fuel can pass and the engine starts and now will run for about 30 seconds.

Any ideas
 

bertsmobile1

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Service info on Mac's is hard to come by but that way of running the fuel lines sounds definately wrong.
So start with the make & model number of the carb.

In most hand helds the fuel tank runs at around 5 to 7 psi
If it gets above 10 to 15 PSA ( the pop off pressure for the diaphragm valve,) the engine will flood out when the diaphragm lifts and fuel is offered to the jets at high a pressure.
 

TheBishop

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It's got a Walbro WT348 carb.

I first had the fuel line going from the tank filter to the pump side of the carb, thru the carb to the primer bulb, and back into the tank.

I saw a video online of a rebuild of a MAC 3516, the same chainsaw as I have, and he said the fuel line on the MAC should be from the tank filter, to the primer bulb, in to the pump of the carb and back into the tank. His MAC 3516 fired up and ran.

Either way it fires and dies. After 12 years I will not give up on it.
 
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Hey Mon Ami ...........

Bert is right and you were right the first time,,, The filter line goes to the pump side of the carb. The side that has 1 big phillips screw....

Then the other line from the carb goes to the primer bulb.... Then the other in the tank to disperse the extra fuel back into the tank.

The fuel must be be pulled thru the carb and not pushed thru the carb.

My offer still stands if you want to take the 30 minute drive over here..... I have fuel filters and line in stock in my shop..... I won't charge you for helping you out. I do that for a lot of people...... I like helping people.........

You might have had the primer hooked up backwards when the lines were hooked up right the first time.....

You do have a runner right there.....

Let us know Mon Ami ..... Plus Tard ~!~!
 

Boobala

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I believe you have the "remote primer" (not on the carb,) .. be sure those lines are placed in the correct position also, one is"in" the other is "out" ..
 

TheBishop

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About 1 1/2 inches. How about you?

I was born in Nashville Tennessee and moved away in 1987. I loved it every time snowed up there. I loved the ice storms where every thing was covered with crystal, and worked outside in it and loved every minute up until 1987.
My mother put so many layers of clothing on me we I fell down I had a lot of trouble getting up. but she had to cause I was going outside to play in the snow clothes or not.

I married a girl from Louisiana 38 years ago, but she wanted to retire in Tennessee. I wanted more time outside so we retired here. Up there I would go crazy being cooped up inside.

After we left and saw winter with little snow and ice and more time outside to work and play, I don't miss it anymore.

It's nice now retired and don't have to go anywhere.
 
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