Oil pan gasket vs RTV sealant - Page 2 - PeachParts Mercedes-Benz Forum

leathermang · #16 10-09-2015, 06:01 PM

Avoid RTV after all my detailed instructions as to how to use it correctly ? I am devastated .

Dan Stokes · #17 10-09-2015, 09:33 PM

Nope, there are 2 pans. The sump that has the oil drain plug is steel and REALLY thick for a sheet metal part. The upper pan bolts up to the engine block and is cast aluminum with tons of reinforcing ribs. If you look near the front of my build thread you'll see pics of both of mine when I had them powder coated. The steel (lower) pan bolts to the upper pan. Mercedes may use a different term for the upper pan but I think the lower one is called the "sump".

Dan

vwnate1 · #18 10-09-2015, 11:00 PM

I'm of the generation that really distrusts anaerobic sealants but , when I was working in a big Diesel truck shop a while back, the Permatex Factory Rep. came by and showed us all this new stuff called " The Right Stuff " ~ it comes in tubes or aerosol cans and is simply amazing .

A *tiny* bit of it does the trick ~ I make a tiny pin hole in the nose of the applicator to spread a 3/16" if not smaller bear then I use my clean fingertip to spread it as thin as can be .

This stuff is and once you've used it , nothing else will do .

As mentioned , both surfaces must be hospital clean before you add any sealant ! I use ether (starting fluid) on a clean white rag until it comes off white , then I smear the tiny bit and have never yet had a leak , weep nor seep .

Best of all , the aerosol can thing lasts for almost ten years ~ you use so very little of it then allow the clear plastic applicator tip to dry out and easily remove that the next time you need it .

RML · #19 10-09-2015, 11:29 PM

Quote:

Originally Posted by leathermang

Avoid RTV after all my detailed instructions as to how to use it correctly ? I am devastated .

I actually love your approach. I stopped at the auto parts store and was looking around the gasket and sealant section and talking to the guy. They had a really nice roll of cork but it measured only 10" wide and the oil pan is 11" wide. I bought some Permatex #2 non hardening sealant but am not sure yet which approach I am going to take. I still might check out the Toyota stuff. I will also stop at another auto parts store or two and see if they have cork that is 11" wide or better.

leathermang · #20 10-09-2015, 11:33 PM

Thanks, I feel much better now.

Here is a good overview.... from some who really know about this stuff .. Hemmings Motor News.... they also deal with older stuff like we do...

http://blog.hemmings.com/index.php/2013/09/13/tech-101-how-to-use-the-right-gasket-sealants/

funola · #21 10-27-2015, 07:06 PM

Quote:

Originally Posted by vwnate1

I'm of the generation that really distrusts anaerobic sealants but , when I was working in a big Diesel truck shop a while back, the Permatex Factory Rep. came by and showed us all this new stuff called " The Right Stuff " ~ it comes in tubes or aerosol cans and is simply amazing .

A *tiny* bit of it does the trick ~ I make a tiny pin hole in the nose of the applicator to spread a 3/16" if not smaller bear then I use my clean fingertip to spread it as thin as can be .

This stuff is and once you've used it , nothing else will do .

As mentioned , both surfaces must be hospital clean before you add any sealant ! I use ether (starting fluid) on a clean white rag until it comes off white , then I smear the tiny bit and have never yet had a leak , weep nor seep .

Best of all , the aerosol can thing lasts for almost ten years ~ you use so very little of it then allow the clear plastic applicator tip to dry out and easily remove that the next time you need it .

Can you please post a link of the aerosol can "The Right Stuff" that lasts 10 years? How long have you had yours and is it still good?

Mark DiSilvestro · #22 10-28-2015, 12:00 AM

On my '84 Euro NA 300TD some time ago, after fishing vacuum-pump bearing-bits out of my oil-pump screen, I wound up using RTV on the lower pan, along with the original gasket, after the local import parts idiot ("My computer says they're all the same!") ordered me a gasket for a turbo motor. No problem for 6 years now.

Happy Motoring, Mark

mannys9130 · #23 10-28-2015, 06:32 AM

Quote:

Originally Posted by Maxbumpo

RTV is supposed to be a big no-no on any engine part exposed to engine oil (in a MB engine). The theory is that a piece of excess RTV can somehow pass through the oil filter and then plug an oil squirter that is cooling a piston, and the piston overheats and seizes and then you have a doorstop.

Logically I don't see how this works, unless the oil filter plugs and goes into bypass mode. I suppose if you had a lot of RTV and other junk in the engine / oil and leave the old oil filter in place, it will quickly be overwhelmed and go into bypass mode, and then you get your very expensive doorstop.

At a cold start, the filter is bypassed almost constantly until the oil warms up and thins out. The RTV booger would need to get past the oil pump screen, but once through that it could be sent right into a jet or a bearing.

Most engines today are sealed with RTV. I think tech has come a ways from when RTV was starting to become known and when you use it correctly it's really your best friend. Thin is the key. No oozing out allowed.

Diesel911 · #24 10-28-2015, 10:52 AM

Does RTV Silcone float to the top of Oil?

vstech · #25 10-28-2015, 11:13 AM

it wouldnt matter if it did... the massive flow of the oil in and out of the passages would quickly submerge even the lightest substance and the suction of the oil pump would pull it into the system.

best to NEVER use so much of it, that ANY gets loose inside the motor!

vwnate1 · #26 10-28-2015, 01:11 PM

Quote:

Originally Posted by funola

Can you please post a link of the aerosol can "The Right Stuff" that lasts 10 years? How long have you had yours and is it still good?

O.K. , the next time I can get into my garage I'll do that .

The can is primarily black .

It lasted almost 15 years before I replaced it , a tiny bit goes a long , long way .

As mentioned , using sealants is delicate work .

Too much and you'll have problems ~ I'll still fishing bits of red RTV out of the OM603 engine on my Brother's 300SDL , some boob used it on the water and vacuum pumps , so far we've lost the cylinder head and the coolant temp goes up and down more than I'd like

.

' The Right Stuff ' is hands down the very best , followed by Hylomar .

RTV's are O.K. I guess , I occasionally use that to position a gasket .

Diesel911 · #27 10-28-2015, 06:09 PM

Quote:

Originally Posted by vstech

it wouldnt matter if it did... the massive flow of the oil in and out of the passages would quickly submerge even the lightest substance and the suction of the oil pump would pull it into the system.

best to NEVER use so much of it, that ANY gets loose inside the motor!

Thanks for the opinion but does that mean you don't know if RTV Silcon floats on Oil?

RML · #28 10-31-2015, 11:42 PM

This past week I put the oil pan back on. After taking another look at the imperfection I have on the flange where the oil pan meets up, and doing a final smoothing of the JB Weld I put on there, I assessed that I had a big enough gap that a cork gasket would be a good idea. So I went to NAPA and asked if they could order a piece of cork wider than 11". They could and did (the other chains could only offer what I saw on the shelf). I liked leathermang's idea of sealing it up on both sides and was also intrigued by The Right Stuff suggested by vwnate1. So I bought a can of The Right Stuff and went to work. I cut a gasket and sealed it up. The Right Stuff dries to a nice rubbery coating in about 5 minutes. I put the pan back on and filled her up with oil.

Today I got my instrument cluster back in. I had to repair the odometer, which was slipping, and repainted the needles while I had it out. (Looks fantastic now.) I put the battery charger on and will start it up tomorrow. I expect to have no oil leaks. I'll report back.

Thank you, leathermang and vwnate1. Appreciate the input.

vwnate1 · #29 11-01-2015, 09:36 PM

Both types are useful ;

You'll find the most important thing to do is the pre work and final cleaning ~ I always clean both metal surfaces with a Hospital clean cloth wetted with Ether (aerosol starting fluid) before applying any sealant .

As mentioned , most of the time folks use too much and let the excess moosh out , one in a blue moon they'll wipe off the external excess but there's still those globs swirling 'round insde the engine waiting to clog something .

I'm keen to hear how you like ' The Right Stuff ' , I was very skeptical until the very first time I used it , ever since nothing else will do .

Remember to leave a plug of it in the nozzle to cure and prevent any air from getting into the can , ruining it .

FWIW , all I work on anymore is old stuff , usually very battered so proper sealing is important to me , I even have a vintage British car that only leaks past the rear main bearing , this because it has NO REAR SEAL (!) .