Does Liqui Moly Motor Oil Saver break down RTV Sealant?

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As above. I'm going to be using a smaller-than-recommended dose (maybe 8-12oz or so in 4qts oil) to see if a tiny rear main seep will be gone by my next oil change. However I'm also aware that there are a bunch of parts of my engine, such as the oil pan, that don't have a gasket - they came with just a bead of RTV from the factory. I also have a little at the corners of my valve cover and timing cover.

(To clarify: I'm using the product for the rear main, not the RTV. The RTV isn't leaking)

I've not used ester-based oils in this engine before, and maybe I'm a little paranoid, but would the Motor Oil Saver be expected to have any destructive effect on RTV sealant, especialy if left in the engine (albeit in small dose) for nearly an entire OCI?
 
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RTV is silicone rubber, not affected. There was an earlier discussion of this same subject, and the consensus was there is no swelling or plasticizer effect on the silicone rubber seals.
 
MOS fixed my Hyundai Accent oil leak RMS. Added full can and filled with PP 5w30. Next oci I did the same but with 1/3 can and after that no weeps of oil. Call 888 moly oil and ask tech support. They should have you fixed up.
 
Originally Posted by oil_film_movies
RTV is silicone rubber, not affected. There was an earlier discussion of this same subject, and the consensus was there is no swelling or plasticizer effect on the silicone rubber seals.


There was a tech bulletin back in the early 2000's that many GM differentials had RTV that was attacked by certain gear oils, even though the oil met the GM spec. The fix was to repair with a different brand of RTV. So his concern about RTV seems to be grounded in real-world problems: if I can find the tech notice I will post it. That said, I have NO idea on the Liqui Moly product in question.
 
Originally Posted by Marco620
MOS fixed my Hyundai Accent oil leak RMS. Added full can and filled with PP 5w30. Next oci I did the same but with 1/3 can and after that no weeps of oil. Call 888 moly oil and ask tech support. They should have you fixed up.


Great to hear! Am I mistaken or do Hyundai oil pans also not come with rubber gaskets but sealed from the factory with just their "Ultra Blue" RTV?
 
The silicones from RTV sealers can leach out into PCMO's so if you do a UOA and see elevated silicon levels there is no need for alarm and the minor leaching does no harm to anything else.
 
Originally Posted by Calikura
Great to hear! Am I mistaken or do Hyundai oil pans also not come with rubber gaskets but sealed from the factory with just their "Ultra Blue" RTV?


Can't speak for all models but my 09 was factory RTV sealed. You might drop an email to the stop leak mfg and ask them that question but I'd be surprised to learn it did. Seems to me that they'd be severely limiting their products suitability if it had a destructive solvent like effect on silicone based RTV's.


Originally Posted by harry j
no problem, RTV laughs at that additive.


That would be my guess too...
 
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Thanks for all the reassuring replies. I wrote to LM and they also assured it would not be a problem. Went ahead and put it in my engine and it has been without problems so far. Hope it works its magic for the seal!
 
Originally Posted by Calikura
Thanks for all the reassuring replies. I wrote to LM and they also assured it would not be a problem. Went ahead and put it in my engine and it has been without problems so far. Hope it works its magic for the seal!


I hope it works too cuzz rear mains aren't easy nor cheap to replace as I'm sure you know by now.
 
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Look at the ingredients and compare them to the products in this chart. Do a search through the list for "ester", you will notice almost all ester related products are not compatible. I have pulled many a pan that RTV was used on OE and pulled of a soggy mess that used to be RTV.
I am not saying all RTV will be effected the same was as I am sure there are different formulations but how would you know.

RTV
 
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