Description
Check the specifications, dimensions, variation details, referenced part numbers, and available fitment evidence before matching this item to an application.
LOCTITE Automotive Klean N’ Prime Activator 7649 is a high-performance primer adhesive designed to enhance the bonding power of anaerobic adhesives, sealers, and threadlockers. This 4.5 oz aerosol can is specifically formulated for use with inactive surfaces such as plated parts, stainless steel, gold, silver, and aluminum. Ideal for low-temperature environments, this activator works reliably across a wide range of metals and passive substrates, ensuring secure adhesion even on challenging surfaces. It accelerates cure times, making it a perfect choice for applications in cold temperatures (below 41°F /
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Parameters, dimensions, material, fitment, and part numbers
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A corrosion & rust inhibitors listing with source specifications kept visible for comparison.
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Customer feedback
Ratings and written reviews
4.7 / 5
303 source ratings
Source: Amazon. Imported marketplace feedback is shown for product research and is not a review of a purchase made on this website.
Martin Demel –
I prepped the main shaft and fifth gear splines off my Dodge NV4500 transmission. It worked so fast, that the Loctite started to cure about 15 seconds after I applied it, causing the fifth gear to stop about halfway while sliding the gear into the main shaft. I had to use a gear pulse to remove it. Then I had to clean all the old Loctite off both surfaces before trying again. Which I did WITHOUT the Loctite Prep!Activator Spray.
Graham –
I used it secure a bearing on a shaft it made locking compound work so fast you need to make sure it’s ready to go right into place it can set up so fast it stops moving all the way into place
Metal Tronics Inc –
Works exactly as described
Bill or Sparkey –
1st off, this product IS NOT intended to clean greasy parts from the get go. It’s merely use as a final clean before assembling your parts. Note: This product contains ACETONE and BUTANE and is highly flammable. Even though Acetone and Butane is not consider extremely toxic on certain web sites, I would consider as such. Meaning, you should be in a WELL ventilated area. I did my work outside and it still can take your breath away. I would highly recommend wearing gloves (e.g. nitrate) while working with it. It will dry the moisture out of your skin. Finally, wear a face shield for eye protection too.I hung my parts [bearing race] on a wire as I sprayed them down and let them dry. It remove any residual oil film on the race. I am using Loctite 660 to glue this bearing in place, due to spinning on its own. All of this is needed to insured that the glue bonds to both metal surfaces for the bearing race.I am well pleased how my project turn out and save me an expensive repair.
day_tripper –
First, “what’s inside”:Acetone 67-64-1 60 – 100%2-Ethylhexanoic acid 149-57-5 0.1 – 1%Isobutane 75-28-5 10 – 30%Basically: cleaner, catalyst, and propellant.I had a knurled grain mill roller with a right-hand-threaded drive shaft that unfortunately I wanted to run in reverse, which mean the shaft would immediately unthread. I picked up some “permanent” Loctite and this “Activator” and after first cleaning both male and female threads to within an inch of their (or my) lives I applied the “Activator” to both parts, let them sit for an hour to ensure both parts were thoroughly dry, then applied the thread locker and screwed in the drive shaft and then let the assembly sit for 24 hours.Tested the mill with a full hopper of grain (~18 pounds) and it plowed through it all with zero issues. Knock on wood :)Cheers!
James R. Bull –
I have four non-tapered stainless steel pipe connections on a heating system storage tank. All attempts to seal the fittings with tape or pipe sealants failed until I primed the fittings with this product, and used Loctite thread sealant. One warning, after applying loctite thread sealer, the sealant begins setting within minutes, so if you prep the threads with this product, keep in mind that it quickly cures thread sealant.For Stainless steel pipe fittings, I highly recommend this product.
Bob –
Did the trick for making a gasket on my JD Gator.
prm –
Expensive. Only option I could find to speed up curing in cold weather application of lock tite bolt retainer.
maineac –
Works as expected