Genuine Husqvarna replacement part, this part is sold individually.
The 503939601 Air Purge does just what the part name says.
It purges the air out of the carburetor.
Then it forces fuel from the fuel tank and fuel line in to the carburetor.
Air Purge 503936601
OEM part for: Husqvarna
Part Number: 503936601
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Product Description ?
- Classification: Part
- Weight: 0.01 lbs.
- Also Known As: Purge Bulb, Plunger, Purge Bubble, Purger Bulb, Primer Bulb
- Shipping: Ships Worldwide
Frequently Purchased Together ?
Compatibility
This Air Purge will fit the following 704 machines. Confirm this part works with your model, and view the detailed model diagrams and repair help we have to offer.
Husqvarna
Show More Compatible ModelsThis item works with the following types of products:
- Chain Saw Parts
- Saw Parts
Customer Part Reviews ?
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Does this fit my product?Questions & Answers for Air Purge
Customer Repair Instructions ?
All our customer repair instructions are solicited directly from other customers just like you who have purchased and replaced this exact part.
Air purge was cracked
Tool Type
Chain Saw
Difficulty
Easy
Time
15-30 minutes
Tools Used
Screwdriver, Pliers
Parts Used
Air purge cracked due to age.
Tool Type
Trimmer
Difficulty
Easy
Time
Less than 15 minutes
Tools Used
Screwdriver, Allen wrench
Parts Used
Used small screw driver to depress the tabs on air purge.
Pulled off both fuel lines from air purge, paying attention to which one connected where.
Attached fuel lines to new air purge and snapped it in place.
It was a very easy and straightforward repair.
Prime bulb return line dry rotted, leaking gas.
Tool Type
Chain Saw
Difficulty
Hard
Time
1-2 hours
Tools Used
Screwdriver, Pliers, Nutdriver, Two picks, one straight, one 90 degrees, knife
2. You can choose to remove carb, I was able to do repair without removing, probably more difficult, but might have saved a little time. I removed return line and fuel lines and prime bulb from saw, followed by grommets. To remove fuel line you have to open gas tank and pull out filter and fuel line with your 90 degree pick. Remove filter and hose, replace with new.
3. When I replaced grommets and hose, I put a little oil on them to make things go on a little easier. I found it is easier to install grommets on hose first and then install grommets on saw. You can always push and pull hose through.
4. Once all hoses are on and secure, reinstall your filter on line and replace inside tank. I cut about two inches off the tank line before installing filter, just because it seemed a little long, your choice. I only had one line that was bad, but I figured while I was replacing one, might as well do them all, the others are probably going to fail soon.
5. In order to replace exhaust screen, you will have to remove chain break handle, two hex head bolts, slide screen out, slide new one in and done.
6. Once installed, I reassembled everything in the reverse order it come out. Chain brake handle, main handle then throttle cover, remember to install throttle linkage, you have to spin it to get back next to the carb, this can be a little tedious, but make sure it is where it needs to go before bolting main handle on, or you have to take it apart again(my mistake).
7. After throttle cover, replace your top cover, and chain and bar, add gas and your good to go.
Would not start cracked air purge bulb
Tool Type
Trimmer
Difficulty
Easy
Time
15-30 minutes
Tools Used
, allen wrench
Parts Used
Note the purge bulb is clocked so it will only seat in one direction.
reassembled.
Leaking gas, and would not run for a full min.
Tool Type
Trimmer
Difficulty
Medium
Time
30-60 minutes
Tools Used
Screwdriver, Socket set, Wrench Set
Parts Used
Pulled bottom plate
Removed gas tank
Removed fuel line and air purge line
Replaced purge bubble
Reinstalled all other parts
Primer punctured
Tool Type
Trimmer
Difficulty
Easy
Time
15-30 minutes
Tools Used
Screwdriver, Pliers
Parts Used
2. Pulled out old primer
3. Removed two fuel lines
4. Placed in the new primer and connected both fuel lines
5. Placed frame back on and screwed in.
Purge cracked would not prime, upon inspection throttle cable appeared severely frayed near the carb, after removing throttle cable, spring was found broken
Tool Type
Trimmer
Difficulty
Medium
Time
30-60 minutes
Tools Used
Nutdriver, Star bit
Air purge pump bulb hardened and split open
Tool Type
Trimmer
Difficulty
Medium
Time
15-30 minutes
Tools Used
Screwdriver, Pliers, Nutdriver
Parts Used
2. Disconnected the two fuel lines from the broken air purge pump.
3. Removed the air purge pump by depressing the snap in bottom with a flat edge screw driver.
4. Positioned the new air purge pump to align with the two fuel lines and made the connection.
5. Being careful not to disconnect the fuel lines, aligned the air purge pump with the snap in cut- outs and pushed into place.
6. Depressed the air purge pump to be sure it worked.
7. Re-installed the top assembly.
fuel lines and air purge old and brittle ('09) Husqvarna 223L Trimmer
Tool Type
Trimmer
Difficulty
Easy
Time
15-30 minutes
Tools Used
Pliers, Allen wrench
Drive shaft broke on one trimmer and air pump for fuel line leaked for other trimmer.
Tool Type
Trimmer
Difficulty
Medium
Time
15-30 minutes
Tools Used
Screwdriver, Pliers, Nutdriver, Allen wrenches
1. Remove side cover and fuel lines from air pump.
2. With screwdriver, push in tab on rear of pump to release from frame.
3. Align new pump in frame and snap into place.
4. Use needle nose pliers to carefully attach fuel lines.
5. Press air pump bulb 3 or 4 times to check for leaks.
6. Reinstall side cover.
Drive shaft on Homelite:
1. Remove trimmer head assembly on end of shaft.
2. Remove safety guard from end of shaft.
3. Remove handle from shaft.
4. Remove throttle assembly from shaft noting how the linkage fits back in casing.
5. Remove clamp noting location.
6. Remove shaft assembly from engine.
7. Install new shaft and tighten clamp in same location as removed. You may need to turn end of the shaft so the new drive shaft slides into engine.
8. Install throttle assembly assuring throttle linkage works as you assemble.
9. Replace handle and safety guard on shaft.
10. Replace trimmer head.
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Our customer service team are at the ready daily to answer your part and product questions. We have a dedicated staff with decades of collective experience in helping customers just like you purchase parts to repair their products.
All our part reviews are solicited directly from other customers who have purchased this exact part. While we moderate these reviews for profanity, offensive language or personally identifiable information, these reviews are posted exactly as submitted and no alterations are made by our team.
All our customer repair instructions are solicited directly from other customers just like you who have purchased and replaced this exact part. While we moderate these reviews for profanity, offensive language or personally identifiable information, these reviews are posted exactly as submitted and no alterations are made by our team.
Based on data from past customer purchasing behaviors, these parts are most commonly purchased together along with the part you are viewing. These parts may be necessary or helpful to replace to complete your current repair.
All our installation videos are created and produced in collaboration with our in-house repair technician, Mark Sodja, who has helped millions of eReplacementParts customers over the last 13 years repair their products. Mark has years of experience in selling and repairing both commercial and residential products with a specialty in gas-powered equipment.
This data is collected from customers who submitted a repair instruction after replacing this exact part. Customers can rate how easy the repair was to complete and how long it took. We aggregate this data to provide a repair rating that allows customers to quickly determine the difficulty and time needed to perform their own repair.