No one locally seams to stock Locktite brand 518. One vendor shows it as a discontinued item. Seeking suggestions for a good alternate product to seal the cam covers without a gasket.
No one locally seams to stock Locktite brand 518.
Loctite’s online documentation shows it still available. 50ml tube is 37394,
and a 300ml cartridge is 37530.
I’ve used 573 and 574 as well, and still have some of them around.
– Kirbert
The Loctite 518 anaerobic product states that is OK to use on aluminum parts but the Pematex anaerobic specifically states not to use on aluminum as it will cause pitting. Don’t know what chemistry differences between the two product are but an very wary about using Permatex to seal the cam covers.
The Loctite 518 anaerobic product states that is OK to use on
aluminum parts but the Pematex anaerobic specifically states not to
use on aluminum as it will cause pitting.
Interesting, as I think they are the same company! And IMHO a gasket
product that pits aluminum would be wholly unacceptable, if I were a
corporation I wouldn’t even put it into production. I’d send it back to the lab
and tell them to keep working on it.
– Kirbert
Both seem to state OK for use on Ali.
However, the loctite document makes reference to Ali with low copper content. I am aware that higher copper content in Ali can lead to pitting corrosion. Perhaps the issue is with the type of Ali. As far as I am aware, many castings have high Cu to lubricate and improve flow. Extrusions will have low Cu. Just speculation on my part.
There is a curious graph in the 518 data showing a 20% strength at temp on Ali.
There is also reference to much reduced strength in the presence of gasoline.
Why oh why are there sooooooo many types of sealant.
Loctite 518-EN.pdf (80.6 KB)
Permatex 51813.pdf (142.8 KB)
Mark
The head and block are LM25 and I am assuming the cam covers are the same…but it is not explicitly stated. LM25 is 0.2% Cu. This is low so probably OK with Loctite 518. I hope so…I have used it everywhere in my engine rebuild!!!
Matt
Find this alloying content information interesting. Not wanting to go against sealant manufactures warnings about not using their product on aluminum found a local source (if 37 miles from here is local) for the Loctite 518. Bought two 50ML tubes. They are marked “NEW” with part number 2096064 on the tube. The new part may be just that they updated the MSDS or that they have improved the product. Before local tax they where $18.00 each. Saw them on line for as much as near twice that.
Nice rainy day today staying home and working on the car. Task remaining are installing exhaust system from the first cat. back, oil cooler, radiator, all belt driven accessories, cam covers, intake manifolds,
fuel injectors and harness and all the engine wiring, fill all fluid levels. Next step will be cross fingers and fire her up for a brief time then check fluid level of transmission since it is newly rebuilt. Wish me luck and thank for this forum of un seen friends.
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Before local tax they where $18.00 each. Saw them on line for as much
as near twice that.
WTH??!!?? What’s wrong with this stuff?
It says right on the package, “Ideal for Aluminum or Cast Iron Flanges”.
– Kirbert
Matt, 0.2% Cu is low. Some of the castings I have seen from China have had 5% Cu and these have been reported to corrode rapidly in the presence of salt air … i.e. if used within a couple of km of the coast. Local importer had to scrap $1million of cast parts from China when they discovered they didn’t meet standard (which I think is either < 0.5% or < 0.2%)
Found this online …
Copper (Cu) 2xxx – The aluminum-copper alloys typically contain between 2 to 10% copper, with smaller additions of other elements. The copper provides substantial increases in strength and facilitates precipitation hardening. The introduction of copper to aluminum can also reduce ductility and corrosion resistance. The susceptibility to solidification cracking of aluminum-copper alloys is increased; consequently, some of these alloys can be the most challenging aluminum alloys to weld. These alloys include some of the highest strength heat treatable aluminum alloys. The most common applications for the 2xxx series alloys are aerospace, military vehicles and rocket fins.