Loctite 574
 

Just a note for the shelf.
574 is on sale on Amazon days, the 250 ml is just over $60.
Less than half the last quote I got.
Bruce

We're required to throw 574 away when it reaches the expiration date. It can't even be on the shop floor. Next time you need some, send me a PM and I'll send you some.

I quit using it eons ago. May or may not set up before the case halves are torqued. Too risky. Love that Dirko.

John, which Dirko are you using?

Cheers

Wouldn't presume to answer for John but we've recently finished an extensive testing regimen on ThreeBond 1184 vs Dirko Grey vs Dirko Grey HT and although the result are remarkably similar, the Dirko Grey HT is the obvious winner.
Compression, cure rating, fuel immersion, twist torque and bead breakaway all were tested and although both Dirko test equally, the HT has a higher temperature rating.
After 15+ years using ThreeBond, Dirko is our new go to sealant.
We offer either in our sealant kit for customer preference.

Thank you Henry.

Cheers

Tricky, indeed.
Although we haven't use 574 on case halves or cam towers for decades, we do find it handt on things like threaded fittings. It also makes a nice security sealant for gaskets that are permanent in nature. A very thin coat on paper gaskets like chain boxes and cam joint rings.
When you say tricky, you're not kidding. We use it to add shear resistance to the case main webs in mag case motors but highly discourage that application if you are the least bit hesitant. The shear strength is worth the risk if you know what you're doing.

A quick follow-up on this tip. We couldn't resist checking it out (Amazon is great with returns) and to our delight, the product is as described and freshly dated.

How does the Permatex Ultra Gray compare to the Dirko and ThreeBond 1184? I recall reading somewhere that it is the same as the 1184, just in a Permatex brand tube. True?

I don't know. If it is indeed a repackage TB1184 I would rate it lower than Dirko HT. Maybe you should do an evaluation and bring your finding.


EDIT: a very quick internet search yielded some important data.
Tensile strength:
Dirko 3.3 ± 0.2 N/mm2 Permatex >2.6 N/mm2
Temperature rating
Dirko -60°C to +285°C (for 24h up to +315°C) Permatex -54 to 232°C (Intermittent, -54 to 260°C)
Elongation at break:
Dirko Grey HT 400 ± 100 % Permatex >120 %

Thank you. I'll buy a tube of Dirko for my next engine project. I remember using an earlier version of Dirko 40 years ago on BMW airhead motorcycles at the cylinder to case joint.

It's not my place to tell anyone what's right or what to use on their engine build. Building these little projects are quite often a bucket list item so emotion comes into it.
What I'm trying to do is help the less experienced builders find a path to success.
40 years ago, we built engines quite a bit differently but having tried and failed over those 40 year, there are some simple truths.
The first one is to set aside ego and internet chatter and listen to those who have had at least modicum of success. SmileWavy

To expand on Pete's Permatex question:
While Permatex Ultra Grey may fall short of the Dirko products (Grey and HT) it looks like Permatex OPTIMUM GREY may compare favorably with Dirko Grey HT.
Tensile strength (which generally refers to break-away resistance) is lower.
Tensile strength and elongation will create a reasonably accurate breakaway resistance.
This is important because you will inevitably have some squeeze-out when joining two machine surfaces. You do not want squeeze-out/break-away traveling through your engine.

I have only used 574 so have no experience with the other products mentioned. It probably comes down to preference but would you recommend 574 for the novice builder because it doesn’t cure as long as it’s exposed to air, and thus reduces the risk of squeeze-out/break-away traveling through an engine?

John and Henry, is the stuff you are seeing success with?

We use it on VW 2.0T cam covers etc... Happy to test it out on aircooled motor builds.

http://forums.pelicanparts.com/uploa...1752888791.jpg

Cheers

Yes