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Helicoil 5521-5 5/16-18 Inch Coarse Thread Repair Kit

Brand: Helicoil

4.7 433 ratings

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$25.63 with 8 percent savings

List Price: $27.83

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Purchase options and add-ons

Leading Manufacturer Of High-Quality Products.Fit Type: Universal
International Renown For Our Diverse Range Of Award-Winning Products
Fully Equipped With State-Of-The-Art Technology
All Products Have Been Designed With The Professional In Mind
Constantly Modernizing Our Powerful Devices To Meet The Demands Of The Modern User
Includes 12 inserts, complete instructions, Heli-Coil tap and installation tool
Used for repairing tapped holes

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Helicoil 5521-5 5/16-18 Inch Coarse Thread Repair Kit

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WARNING: California’s Proposition 65

Product Description

Helicoil Inch Coarse Thread Repair Kit includes inserts, detailed instructions, Heli-Coil tap and installation tool. It is made from high quality material and is extremely long lasting. This inch coarse thread repair kit is used for repairing tapped holes which have been stripped or damaged, due to wear, corrosion and over torque. It comes with a package type of durable placon or vinyl pouches.

Product information

Technical Details

Manufacturer

‎Heli-Coil

Brand

‎Helicoil

Model

‎Helicoil 5521-5 5/16-18 Inch Coarse Thread Repair Kit

Item Weight

‎3.2 ounces

Product Dimensions

‎4.4 x 0.5 x 3.6 inches

Country of Origin

‎China

Item model number

‎5521-5

Is Discontinued By Manufacturer

‎No

Exterior

‎Smooth

Manufacturer Part Number

‎5521-5

OEM Part Number

‎5521-5

Additional Information

ASIN

B0002SRDUU

Customer Reviews

4.7 433 ratings

4.7 out of 5 stars

Best Sellers Rank

#175,393 in Automotive (See Top 100 in Automotive)
#26 in Thread Spark Plug Thread Repair Kits

Date First Available

October 2, 2001

Warranty & Support

Amazon.com Return Policy:Amazon.com Voluntary 30-Day Return Guarantee: You can return many items you have purchased within 30 days following delivery of the item to you. Our Voluntary 30-Day Return Guarantee does not affect your legal right of withdrawal in any way. You can find out more about the exceptions and conditions here.

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What's in the box

Helicoil - Kit 5/16-18 (5521-5)

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	This Item Helicoil 5521-5 5/16-18 Inch Coarse Thread Repair Kit	Recommendations BILITOOLS 1/4-20 inch Thread Repair Kit, HSS Drill Helicoil Repair Kit SAE	dummy BILITOOLS 5/16-18 inch Thread Repair Kit, HSS Drill Helicoil Repair Kit SAE	dummy BILITOOLS Thread Repair Kit SAE, 131-Piece HSS Drill Helicoil Repair Kit 1/4" 5/16" 3/8" 7/16" 1/2"	dummy JMMRRR 30PC SAE Thread Repair Kit 5/16-18 inch HSS Drill Helicoil Repair Kit for Internal Screw Holes Repairing (Blue)	dummy Orion Motor Tech Helicoil Thread Repair Kit, 5/16"-18 Thread Repair Tool Set with HSS Drill Bit & 30 Thread Inserts, SAE Thread Repair Installation Kit for Rethreading Internal Threads with Carry Case
	Try again! Details Added to Cart	Try again! Details Added to Cart	Try again! Details Added to Cart	Try again! Details Added to Cart	Try again! Details Added to Cart	Try again! Details Added to Cart
Price	-8% $25.63 List: $27.83	$9.99	$15.99	$39.99	$15.99	$15.99
Delivery	Get it as soon as Saturday, May 11	Get it as soon as Saturday, May 11	Get it as soon as Saturday, May 11	Get it as soon as Saturday, May 11	Get it as soon as Saturday, May 11	Get it as soon as Saturday, May 11
Customer Ratings	4.7433	4.51,516	4.51,516	4.51,516	4.330	4.4364
Easy to use	4.8	4.4	4.4	4.4	3.8	4.3
Value for money	4.7	4.4	4.4	4.4	3.6	4.0
Durability	5.0	4.1	4.1	4.1	—	3.6
Easy to install	4.8	4.3	4.3	4.3	—	—
Softness	—	3.3	3.3	3.3	—	—
Sold By	Amazon.com	BILITOOLS	BILITOOLS	BILITOOLS	teele	Orion Motor Tech Direct

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Customer reviews

4.7 out of 5

433 global ratings

How customer reviews and ratings work

Customers say

Customers like the performance, ease of installation, quality and value of the auto accessory. For example, they mention it works well, it's easy to install and the parts are good. Some appreciate the ease of repair and value for money.

AI-generated from the text of customer reviews

30 customers mention30 positive0 negative

Customers are satisfied with the performance of the auto accessory. They mention that it works well on head bolts, repairing intake manifolds, and holes in aluminum blocks.

"I used it for furniture repair and it worked perfectly no need to go buy a new piece of furniture when you can repair it with this of course you..." Read more

"These worked great. In the end I has to use 2 in the same hole and cut the top one to. Holding solid now." Read more

"Fixed two stripped threads on my 57 Chevy's hood. Worked so well, I installed these Helicoils on the other two threads just because they were old..." Read more

"Standard item. Works well." Read more

15 customers mention15 positive0 negative

Customers find the installation of the thermostat easy. They mention that the aluminum head and tapping was straight forward. They also say that the helicoil kit made it easy to fix.

"...It was easy to drill through the aluminum head, and tapping was straight forward. The tap was extremely sharp, and bit into the aluminum right away...." Read more

"...Helicoil makes a good product, the bottom part snaps right off cleanly as it should. Just drill, tap, insert and you are back in business...." Read more

"...Voilà! Tapped hole, helicoil goes in easily, thermostat housing sealed (using "The Right Stuff" -good stuff!), all is well." Read more

"...The Helicoil kit made it super easy to fix though. Just drilled it out and tapped it...." Read more

15 customers mention15 positive0 negative

Customers are satisfied with the quality of the auto accessory. They mention that it's an outstanding product, excellent quality, and holds to the same quality that Helicoil has had for years. Some say that the bottom part snaps right off cleanly as it should.

"...Helicoil makes a good product, the bottom part snaps right off cleanly as it should. Just drill, tap, insert and you are back in business...." Read more

"The PRODUCT is just fine...." Read more

"...Worked up to the proper drill size, used the tap which is an excellent quality item, installed said Heli-Coil...." Read more

"The parts were good...The problem I had was the picture didn't match the product..The picture shows a triangular installation tool..There wasn't one..." Read more

9 customers mention9 positive0 negative

Customers appreciate the value of the auto accessory. They say it's a great money saver versus taking the head to a machine shop for re-tapping. Customers also say it is a very useful kit.

"Good price and quick shipping." Read more

"...Huge money saver versus taking the head to a machine shop for re-tapping." Read more

"This thing saved me a bunch of money. I drilled the hole out with the correct bit, taped the hole and crewed in the insert...." Read more

"Pricey but worth it. Bought a cheaper kit on here and was junk. You must buy this brand if you want your job to go smooth." Read more

8 customers mention8 positive0 negative

Customers find the thread repair kit easy to use. They mention it's a terrific repair tool, and that the helicoils are fantastic.

"...it with this of course you have to know how to use it it's a terrific repair tool I`ve been using them now for about 50 years and it's never failed me" Read more

"These helicoils worked great to repair handle on my drill press." Read more

"Helicoils are fantastic!!! Best way to repair a stripped thread ever. Saved the engine block on my old cub cadet garden tractor with it." Read more

"Helicoil one of life’s great inventionsEasy to use great repair / fix tool" Read more

4 customers mention0 positive4 negative

Customers are disappointed that the auto accessory kit does not include a drill bit.

"This fixed my stripped threads. I do wish it came with the drill bit though...." Read more

"The kit is not a kit. No drill bit and no tool to break off installation tang on coil. For the price the kit should have the correct drill bit...." Read more

"...Worked great. This kit does not include a drill bit, but does give drill size if you need to drill out the hole...." Read more

"It works very well, but no associated drill bit is included as with some other like namebrands...." Read more

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Top reviews from the United States

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JOHN WERNER

you can use this tool to repair a variety of different products

Reviewed in the United States on February 3, 2023

Verified Purchase

I used it for furniture repair and it worked perfectly no need to go buy a new piece of furniture when you can repair it with this of course you have to know how to use it it's a terrific repair tool I`ve been using them now for about 50 years and it's never failed me

Helpful

Jerry

Works as it should

Reviewed in the United States on February 19, 2024

Verified Purchase

Fixed up an aluminum lower intake

Helpful

Donald L. Whitt

Die

Reviewed in the United States on December 3, 2023

Verified Purchase

Good price and quick shipping.

Helpful

W. R. W.

Works fine

Reviewed in the United States on January 27, 2023

Verified Purchase

Used it to put durable threads into a piece of plexiglass and it worked fine.

Helpful

Aaron D.

Easy fix for first time user

Reviewed in the United States on December 17, 2014

Verified Purchase

I got a riding lawn mower with the home I just purchased, and the exhaust manifold and muffler were just dangling from the cylinder head. One of the exhaust manifold studs was stripped and had to be drilled out, and the other stud had been removed but the threads destroyed by the prior owner forcing a non-matching screw into the hole. I did some research on alternatives to taking the head off to have it drilled and tapped at a machine shop and found this handy kit.

It was super easy. Inscribed on the tap was the drill bit size needed, 21/64", which I had on hand. It was easy to drill through the aluminum head, and tapping was straight forward. The tap was extremely sharp, and bit into the aluminum right away. I was nervous that it would go in crooked, but the taper at the tip of the tap helped alleviate my concern. I cut about a half turn, then backed off slightly, blew compressed air into the hold to force out the shavings, then repeated, until I had made it all the way to the back of the hole. The tap screwed back out relatively easily. After blowing compressed air into the freshly tapped hole to remove aluminum shavings, the thread insert screwed right in by hand using the included tool. Total time for both holes was about 15 minutes.

My only complaint is that the notch at the end of the thread insert didn't seem to be "notched" enough for the tang at the end to easily snap free. It took several whacks and eventually reaching back in there with tiny needle nose pliers to finally get it out. For that reason, I'm knocking off a star.

Overall I'd definitely buy another kit if I need them in another size. Huge money saver versus taking the head to a machine shop for re-tapping.

4 people found this helpful

Helpful

K. Wilson

Helicoil, works as it should,

Reviewed in the United States on May 10, 2021

Verified Purchase

This particular size did not work for me as the drill and tap size turned out to be to large of a dia. for the material I was repairing. Not the fault of the helicoil, just a poor material challenge. I was however able to use my smaller helicoil setup to accomplish the repair, I just ordered a size smaller bolt and I am sure I will be fine. Helicoil makes a good product, the bottom part snaps right off cleanly as it should. Just drill, tap, insert and you are back in business. People say you don't need a threadlocker etc. to keep it in the hole, and that may be true, but I use a bit of blue thread lock anyway...belt and suspenders guy ya know...........

Helpful

Frank Nickel

slick invention

Reviewed in the United States on September 30, 2023

Verified Purchase

pretty much the only way to repair stripped out threads. Good Days

Helpful

queen bee

Value

Reviewed in the United States on October 16, 2023

Verified Purchase

The car