Experimental TEFLON Crankcase Seal / Nc250/Zs177mm

[Co2]

Zs177mm/Nc250 moto block crankcase has not have metal or paper or.. a seal, just i see on surface very thin probably slikon / or high temp plastic seal trace .

Many forums,and my friends sad replacement crankcase seal methode(if not find, fabricated original seal) slicon applicated , offcourse me too try that , but crankcase in surfaces very thin , and i fear if much more applicated that slicone=very badly engine damaged/blocked oil pump/bearings/oil channels/filters/gears, and i just tested 2x time slicone.


Very thin applicete slicone+sponge , my moto master friend sad, use a sponge and very very thiner app slicon , and vibrated+impacted sponge slicon seal is form better thin than a paper , i make that and test again screws mounted waiting dry = crankcase in , badly situtaion (out case not important ofcrs.) failed.


İnside of crankcase better leak.

Slicon seal not for me, i understand , but i need a seal material, perfect temperature , oil strenght , what is material what is... think think ... happy end , i find that TEFLON band...

http://i.hizliresim.com/qRmDM5.jpg

Used a 19mm Teflon band , making double layer , and roll thread , crankcase in applied , Teflon thread and aluminium surfaces incompatible , just need very low profile applied a glue(glue type is dry soft glue, not Japan type, or steel type.)


This methode is experimental think.. , my moto need refesh paint+eectrical replacement , proobably 2 weeks or more time need completed, after i returned here and writied here , i hope this methode is ok.

Never try this methode , just wait my test results.

[jimjr21]

I have never seen teflon tape used in this capacity in over 30 years of engine rebuilding.

Personally I use Wurth brand Flange Sealant Green. It was developed for Rolls Royce aircraft engines to seal machined surfaces.

I most commonly see engines with Yamabond or Hondabond sealing them. Again products designed to properly seal an internal combustion engine coming in contact with oil, fuel, coolant, etc.

I will be looking to see your results. I hope they are positive.

I worry that the tape rolled will have too much thickness and distort the machined tolerances and alignment.

[SpudRider]

I have seen gaskets for the ZS177MM (NC250) engine sold at Taobao. However, I don't remember seeing a gasket for mating the crankcase halves.

https://gd1.alicdn.com/bao/uploaded/i1/TB1T36fHFXXXXa8XpXXXXXXXXXX_!!0-item_pic.jpg

https://item.taobao.com/item.htm?spm=a230r.1.14.38.Ti1fVs&id=45070701117&ns=1&abbucket=12#detail

[SpudRider]

I have never seen teflon tape used in this capacity in over 30 years of engine rebuilding.

Personally I use Wurth brand Flange Sealant Green. It was developed for Rolls Royce aircraft engines to seal machined surfaces.

I most commonly see engines with Yamabond or Hondabond sealing them. Again products designed to properly seal an internal combustion engine coming in contact with oil, fuel, coolant, etc.

I will be looking to see your results. I hope they are positive.

I worry that the tape rolled will have too much thickness and distort the machined tolerances and alignment.

Jim,

Can you recommend any of the Permatex gasket makers?

http://www.permatex.com/products-2/product-categories/gasketing/gasket-makers

[Co2]

I have never seen teflon tape used in this capacity in over 30 years of engine rebuilding.

Personally I use Wurth brand Flange Sealant Green. It was developed for Rolls Royce aircraft engines to seal machined surfaces.

I most commonly see engines with Yamabond or Hondabond sealing them. Again products designed to properly seal an internal combustion engine coming in contact with oil, fuel, coolant, etc.

I will be looking to see your results. I hope they are positive.

I worry that the tape rolled will have too much thickness and distort the machined tolerances and alignment.

Amazing experience sir , i'm just trust crankcase in surfaces layers very sharpness and flat build , and first time demntage crankccase seeing original seal remainder has very thick.

Photos first try's , latest version better visual and reasuring ,smooth.

İhope to, that methode succes... if failed 4. time demontaged moto block:grr:

[Co2]

I have seen gaskets for the ZS177MM (NC250) engine sold at Taobao. However, I don't remember seeing a gasket for mating the crankcase halves.



https://item.taobao.com/item.htm?spm=a230r.1.14.38.Ti1fVs&id=45070701117&ns=1&abbucket=12#detail

Yes not original gasket , i think/probably in crankcase surfaces very grift much more cuted surfaces multiple layers = hardjob:lol:

Gaskets on picture, little camshaft tensioner , cylinder up+down , clutch decorative case, waterpump ,stator case , and bigger right crankcase side gasket's.

Sorry worng word of topic "Seal" , " Gasket bettter.

[humanbeing]

The chinese stuff: http://www.huitian.net.cn/product_intro.asp?id=141

[Weldangrind]

I've used Three Bond and Loctite 518 with good results.

[SpudRider]

I've used Three Bond and Loctite 518 with good results.

I really like the Permatex Ultra Black RTV. I use it for a variety of purposes. Which of the Permatex products do you think would work best to seal the two crankcase halves?

http://www.permatex.com/products-2/product-categories/gasketing/gasket-makers

[SpudRider]

I did a little research, and a lot of people swear by Permatex Ultra Grey. :)

http://forums.g2ic.com/showthread.php?199659-hondabond-vs-RTV
http://www.k20a.org/forum/showthread.php?t=94798

http://www.permatex.com/products-2/product-categories/gasketing/gasket-makers/permatex-ultra-grey-rigid-high-torque-rtv-silicone-gasket-maker-detail

http://shop.advanceautoparts.com/wcsstore/CVWEB/staticproductimage//N2131/large/7160017_ptx_82194_pri_larg.jpg

[Co2]

Hmm , my that project started i fear in the crankcase owerflow all semifiluid gasket materials , and blocked any actioned in motor parts fear , that all semifuid materials finded easy , but crankcase two surface closed very sharp/thick surfaces , if any semifuid used 100% owerflow in motor.

Probably first montage from moto factory using a robotic gasket aplication, and perfect montaged, first demontaged crankcase surfaces very very thinner gasket how i can description idk probably gasket material thickness 0.01 -0 .03 mm maximum all effort so that , leaked semifluids.

İ hope , that semi elastic material, tolarated that problem i hope.

[jimjr21]

Jim,

Can you recommend any of the Permatex gasket makers?

http://www.permatex.com/products-2/product-categories/gasketing/gasket-makers

Any of those products will work to seal the crankcase.

As others pointed out the gray is a good all around choice.

[Mudflap]

My favorite is Loctite 518 or whatever Permatex calls it nowadays. I used it for years on motorcycle crankcases, Rotax aircraft engines, washing machine transmissions, and everything else that did not need the spacing of a paper gasket.

[Weldangrind]

My favorite is Loctite 518 or whatever Permatex calls it nowadays. I used it for years on motorcycle crankcases, Rotax aircraft engines, washing machine transmissions, and everything else that did not need the spacing of a paper gasket.

X2.

I've had similar results with Three Bond. I would not use silicone.

[SpudRider]

I've used Three Bond and Loctite 518 with good results.

My favorite is Loctite 518 or whatever Permatex calls it nowadays. I used it for years on motorcycle crankcases, Rotax aircraft engines, washing machine transmissions, and everything else that did not need the spacing of a paper gasket.

We have two respectable votes for Loctite 518. :)

http://www.loctite.co.uk/loctite-4087.htm?nodeid=8802626633729

http://hybris.cms.henkel.com/medias/sys_master/8798531026974.jpg

[Co2]

Loctite 518 is awesome solved material , thinner applicated yes this best, but 50 ml loctite 518 from here 50 dollares:hi:

[SpudRider]

X2.

I've had similar results with Three Bond. I would not use silicone.

Did you use Three Bond 1104, 1211, or another product?

http://kzrider.com/archive/viewthread.php?tid=18859

Seriously, I have had very good results using Permatex Ultra Black. It was recommended to me by my good friend Andy, who is a professional diesel mechanic with over thirty years of experience.

My Honda XR650L has a steel gasket for the valve cover. We commonly reuse this steel gasket, since it is not deformed during installation. When I did a top end rebuild of my Honda XR650L engine, I applied a thin coat of the Permatex Ultra Black to the steel gasket, and it did a very good job. :)

Also, the oil sight glass in the engine of my Zongshen Sierra 200 became loose after 50,000 miles or so. This engine is virtually identical to the engine in the Yamaha TW200 motorcycles. The oil sight glass is surrounded by a rubber grommet, and is held in place in the right crankcase cover by friction. My friend Andy recommended I seal it in place with Permatex Ultra Black. I followed his advice, and the repair is still in excellent shape after 20,000 miles. :)

I just talked with my friend Andy, and asked him a few questions. Andy likes the high oil resistance of Permatex Ultra Black. He has used this sealant at work for many years. However, he stresses it is vital to clean the mating metal surfaces with brake cleaner, to remove all traces of engine oil. If any engine oil remains in the pores of the metal, the seal will leak. However, cleaning the metal with brake cleaner, et cetera, allows the sealant to enter the pores of the metal and make an excellent bond.

Andy used Permatex Ultra Black at his old workplace for many years. At his new workplace they use Permatex Ultra Grey. These sealants are not deteriorated by engine oil, which can dissolve some other sealants, and send chunks of material into the bearings, destroying them.

[Weldangrind]

I'm with you on all of the Permatex silicone products, and each colour has a specific use. Black is resistant to gas and oil, red is for high heat applications, blue is safe for sensors and clear is good for glass. Grey is at another level, and I think it approaches aerospace grade.

All that said, I would not use silicone on the mating surfaces of two case halves. A superior flange sealant is your best bet.

[ripcuda]

I recommend ThreeBond 1211 and 1184. 1211 is more siliconey and caulk-like when applying. Still a little plyable when dry. 1184 is cheaper... grey... a tad more liquidy than 1211... easier to run a bead. 1184 is more hard when dry.

I've had great success using both on case halves and other metal-to-metal sealings on my 2-stroke and 4-stroke rebuilds. (jet ski recreational and racing engines)

Cheers!

[Co2]

Teflon band is OK ,

Warn : only if u cant found special locktite or another slicone/mastic gasket material, use that methode and applicate very thin job and master hand skill :)

im wait using period and tested any leak of oil, but it work no problem.