I'm doing a service on a Ford Sterling rear end and the instructions on the tube of Permatex Ultra Black RTV (I'm out of the green stuff) say to let it set an hour with the bolts finger tight before torquing and then wait 24 hours before adding the fluid. I can't imagine that there is a single pro out there that can afford to wait 24 hours before adding the fluid and clearing their bay for the next job. Am I right?
Are there any professional mechanics that actually let RTV cure for 24 hours?
- Thread starter ripcord
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Permatex "The Right Stuff" allows return to service in 1 minute. https://www.permatex.com/products/gasketing/black-gasket-makers/permatex-the-right-stuff-black-1-minute-gasket-maker-5-oz/#:~:text=Permatex®s The Right,lasting than pre-cut gaskets. The Permatex website has many free training videos. I check it for new products and selecting the best product for a particular application before buying a sealant.
I never have. Never a problem either
99% of them use Right Stuff instead of the regular RTV.
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Yep, this stuff is amazing. I remember when it came out, around 2003+/-. A real game-changer. It does not particularly like to come apart again though!
You're right, but if it was something causing me concern, I'd use rtv last thing of the day and let it cure overnight.
If a gasket is not available I just cut one out of suitable gasket material like Felpro 3137. It is easy to do with scissors, razor knife and a hole punch. The last thing I use is RTV.
The liquid gaskets including RTV seal better and longer than physical gaskets. Physical gaskets have two leak points on either side, and those leaks are greater when the parts being sealed aren't perfectly flat. Liquid gaskets have technically no leak points as they bond the two parts together and filling some variances between the mating surfaces.
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I had an Indy MB shop let it sit overnight when I had the VCG's replaced. I asked them why they had to keep it overnight and that's what they said. RTV needs to set up.
You keep saying that but it is in general false. Most RTV products weaken badly when subjected to oils, it has its place but generally a gasket made from the proper material for the application is a much better seal. The reason OE use a lot of RTV is ease of automated application on perfectly clean and dry surfaces and the fact that the parts may not see fluids for a long time.
What if it takes 2 minutes or longer to apply a bead around a large part like a transmission case? The RTV will be curing before the parts are assembled. Not a good thing. Plus, whatever chemicals that allow a fast cure, compromise strength. If you don't have the 24 hours to wait, maybe find some other product.
Well, I gave it about 9 hours between torquing and filling. I'm not expecting any issues, but I guess I'll find out. The rig has about 200k on it and I could tell the fluid had been changed at least once by the orange RTV the last guy (excessively) used, though I can't fault him too much as at least it didn't leak.
There was a good amount of metallic shmoo at the bottom of the case and a good bit of metallic gunk built up on the speed sensor that seemed to be causing the speedometer to be twitchy. I don't know if stuck fill plugs are a thing on these Ford Sterling axles, but I had to fill this one through the speed sensor hole like with my personal rig. I put 3 and a third quarts in, splitting the difference between specs that I saw saying 6.5 pints and 7 pints of capacity.
There was a good amount of metallic shmoo at the bottom of the case and a good bit of metallic gunk built up on the speed sensor that seemed to be causing the speedometer to be twitchy. I don't know if stuck fill plugs are a thing on these Ford Sterling axles, but I had to fill this one through the speed sensor hole like with my personal rig. I put 3 and a third quarts in, splitting the difference between specs that I saw saying 6.5 pints and 7 pints of capacity.
Professional oem rtvs do not need 24 hours. So NO
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