Installing a Roper Sloppage Sheet

[gstallons]

I use this stuff : Hylomar , on the oil pan gaskets when assembling this . Just enough to cover both sides of the gasket . If it just comes out the side of the gasket when tightened , it is right. When you disassemble , the gasket does not stick and will come off in one piece w/o tearing.

[audiomick]

On 1/19/2024 at 5:06 PM, docc said:

...@swooshdave's .... video:

https://www.v11lemans.com/forums/topic/20671-roper-plate-redux/?do=findComment&comment=242469

 

Watched that today. Thanks very much @swooshdave 

[Pressureangle]

On 1/20/2024 at 5:30 AM, gstallons said:

I use this stuff : Hylomar , on the oil pan gaskets when assembling this . Just enough to cover both sides of the gasket . If it just comes out the side of the gasket when tightened , it is right. When you disassemble , the gasket does not stick and will come off in one piece w/o tearing.

I don't remember where I learned the history of Hylomar - we used it at H-D, but not at the factory's recommendation.

It was developed by Rolls-Royce to join 'non-precision' joints in aircraft, as during wartime production quality was imperfect, gaskets cost money and took time to replace and carry in inventory as mechanics had to scrape and replace them. Hylomar seals joints that carry lube well, doesn't harden, and applies easily. Good stuff. I used to use it as a base gasket on the racing sportsters, as we got another .015" of compression by eliminating the gasket. Never leaked. 
Would probably work in place of gaskets on a Roper plate, but I was scared to try it...if I have either of mine off I'll use Hylomar instead of gaskets and see how long it lasts.

Edited October 27 by Pressureangle

[PJPR01]

Hylomar also worked for me to get rid of a persistent but small leak on the fuel sender under the tank that connects to the fuel line...just enough on the threads and on the back of the thermistor sealed it all up...NO leaks!

[audiomick]

My "flat-mate" in the garage has a tube of Hylomar. I'll probably use that to seal the new timing sensor, if I ever get around to putting it in. I've only heard good things about that stuff. 

[gstallons]

4 hours ago, Pressureangle said:

I don't remember where I learned the history of Hylomar - we used it at H-D, but not at the factory's recommendation.

It was developed by Rolls-Royce to join 'non-precision' joints in aircraft, as during wartime production quality was imperfect, gaskets cost money and took time to replace and carry in inventory as mechanics had to scrape and replace them. Hylomar seals joints that carry lube well, doesn't harden, and applies easily. Good stuff. I used to use it as a base gasket on the racing sportsters, as we got another .015" of compression by eliminating the gasket. Never leaked. 
Would probably work in place of gaskets on a Roper plate, but I was scared to try it...if I have either of mine off I'll use Hylomar instead of gaskets and see how long it lasts.

I would be afraid to use it (only) where oil passages exist for lubrication. 

[audiomick]

11 minutes ago, gstallons said:

I would be afraid to use it (only) where oil passages exist for lubrication. 

You're absolutely right. I used a silicon based sealant for the crankcase on my V35 Imola when I put it back together after taking it completely apart after I bought it. I was confident that that was not a completely stupid idea because the manual for the Z series Kawasakis stipulated Kawasaki Bond for that application. That is also a silicon based sealant. However, I made about 5 attempts using less and less of the sealant before I was satisfied the the amount applied was little enough to not have any spillage into the oil galleries. 

 

[Pressureangle]

53 minutes ago, gstallons said:

I would be afraid to use it (only) where oil passages exist for lubrication. 

Not intended for pressurized joints. Stuff like base gaskets, crankcase segments, gearcases.
That said, the Roper plate and block/sump surfaces are nice flat joints of high quality material. And we don't carry 80psi of oil pressure. Would not take long to know it doesn't work.

 

Edited October 28 by Pressureangle

[audiomick]

1 minute ago, Pressureangle said:

Not intended for pressurized joints. Stuff like base gaskets, crankcase segments, gearcases.

Yes, I believer that is the case.

[gstallons]

The important thing about Hylomar is that it never hardens like other compounds.  RR uses it in their jet engines because it stays live and will enlarge and contract with the metals in the engines.  I think Lycoming uses Hylomar and a single silk thread string to join all the engine halves and mating surfaces.  If the aircraft companies use this it must be good. 

[audiomick]

3 minutes ago, gstallons said:

 If the aircraft companies use this it must be good. 

Instinctively, I reckon you're right. It might be interesting to hear (read) what @Lucky Phil has to say about that. 

[docc]

6 minutes ago, gstallons said:

The important thing about Hylomar is that it never hardens like other compounds.  RR uses it in their jet engines because it stays live and will enlarge and contract with the metals in the engines.  I think Lycoming uses Hylomar and a single silk thread string to join all the engine halves and mating surfaces.  If the aircraft companies use this it must be good. 

The seasoned Airframe and Powerplant Mechanic ("A&P") that took me under his wing (literally!) as a youth learning mechanics and engine rebuilding taught me this "silk thread" trick putting my Volkswagen motor back together (same configuration as the Lycoming and Continental opposed cylinder motors).

I must (MUST!) remember to add this step when I attempt, one more time, to seal mySport's shift plate . . .

Thanks for posting that, @gstallons!

[Lucky Phil]

5 minutes ago, audiomick said:

Instinctively, I reckon you're right. It might be interesting to hear (read) what @Lucky Phil has to say about that. 

Yes I've been using Hylomar or Rolls Royce compound for many years on jet engines. I also used it on my Roper plate in addition to the std gaskets. I'd actually like to see the Roper plate surface finish around the gasket face on both sides a bead blasted finish which I could do these days but I didn't have my blasting cabinet set up when I fitted mine.

Phil

[Lucky Phil]

1 minute ago, docc said:

The seasoned Airframe and Powerplant Mechanic ("A&P") that took me under his wing (literally!) as a youth learning mechanics and engine rebuilding taught me this "silk thread" trick putting my Volkswagen motor back together (same configuration as the Lycoming and Continental opposed cylinder motors).

I must (MUST!) remember to add this step when I attempt, one more time, to seal mySport's shift plate . . .

Thanks for posting that, @gstallons!

The silk thread isn't an old mechanics trick docc it's actually a requirement in Lycoming piston engines per the maintenance manual. Don't get too committed to Hylomar and the silk thread though as both are technically redundant these days. The silk thread esp. Modern liquid sealants are way better than 60 year old tech. 

[po18guy]

57 minutes ago, Pressureangle said:

Not intended for pressurized joints. Stuff like base gaskets, crankcase segments, gearcases.
That said, the Roper plate and block/sump surfaces are nice flat joints of high quality material. And we don't carry 80psi of oil pressure. Would not take long to know it doesn't work.

 

Oil leaks? Heck, we have various weeping banjo fittings to monitor for that.