R/C Tech Forums

R/C Tech Forums (https://www.rctech.net/forum/)
-   Onroad Nitro Engine Zone (https://www.rctech.net/forum/onroad-nitro-engine-zone-71/)
-   -   strange covered hole in novarossi?? (https://www.rctech.net/forum/onroad-nitro-engine-zone/312685-strange-covered-hole-novarossi.html)

TomB 07-17-2009 03:08 AM

strange covered hole in novarossi??
 
I've taken apart my MAX SL3 for a clean and a bearing replacement and found this hole leading to the front bearing which was blocked with a soft metal material.

does anyone know why this hole is blocked? here are two pics of it unblocked

http://i175.photobucket.com/albums/w...1/P1010727.jpg
http://i175.photobucket.com/albums/w...1/P1010730.jpg

i've seen this hole on an old NS12 novarossi blocked up as well. is this an oil hole? why is it blocked? the hole leads from the entry of the carby where the crank fits through through to the face of the bearing.

i unblocked it with a large sewing pin and pushed the material out of the hole and will run the engine soon. here is a pick of the material, it is a soft type metal:confused: same as the material i found in the NS12 a few years ago.

http://i175.photobucket.com/albums/w...1/P1010728.jpg

i'll be taking apart my XXL3 to see if it has the same hole. I'll probably unblock it as well if i don't see any deterioration in performance or runtime in my SL3

stefan 07-17-2009 03:47 AM


Originally Posted by TomB (Post 6078805)
I've taken apart my MAX SL3 for a clean and a bearing replacement and found this hole leading to the front bearing which was blocked with a soft metal material.

does anyone know why this hole is blocked? here are two pics of it unblocked

http://i175.photobucket.com/albums/w...1/P1010727.jpg
http://i175.photobucket.com/albums/w...1/P1010730.jpg

i've seen this hole on an old NS12 novarossi blocked up as well. is this an oil hole? why is it blocked? the hole leads from the entry of the carby where the crank fits through through to the face of the bearing.

i unblocked it with a large sewing pin and pushed the material out of the hole and will run the engine soon. here is a pick of the material, it is a soft type metal:confused: same as the material i found in the NS12 a few years ago.

http://i175.photobucket.com/albums/w...1/P1010728.jpg

i'll be taking apart my XXL3 to see if it has the same hole. I'll probably unblock it as well if i don't see any deterioration in performance or runtime in my SL3

Now you've done it :eek:

This hole must be closed or your engine will be leaking at the fron bearing like nuts.

This is some kind of production hole. I opened it up once and it was a real mess. I did stick a tooth pick in it and ciút it of clean, no kidding.

TomB 07-17-2009 03:50 AM


Originally Posted by stefan (Post 6078858)
Now you've done it :eek:

This hole must be closed or your engine will be leaking at the fron bearing like nuts.

This is some kind of production hole. I opened it up once and it was a real mess. I did stick a tooth pick in it and ciút it of clean, no kidding.

ok cool, i'll just block it back up with some jb weld;) i put the bearing in the wrong way anyway:o the XXL3 has the bearing balls facing the inside but the SL3 has them facing to the outside:o:weird: i took the rubber sheild of to avoid any possible damage from the heat of the oven and lost track of which way it went

i think from memory when i unblocked the hole in the NS12 it didn't hold idle well when entering the pits for a refuel, which would make sense with the whole airleak situation

Roelof 07-17-2009 04:43 AM


Originally Posted by stefan (Post 6078858)
This hole must be closed or your engine will be leaking at the fron bearing like nuts.

Weird. With our engines without this hole we had a leak of oil and with this hole it is gone. It seems to build up or take away some pressure preventing oil to come out of the bearing.

TomB 07-17-2009 05:12 AM


Originally Posted by Roelof (Post 6078939)
Weird. With our engines without this hole we had a leak of oil and with this hole it is gone. It seems to build up or take away some pressure preventing oil to come out of the bearing.

interesting, i'll try it out before i block it back up, just incase.:)

Riketsu 07-17-2009 12:41 PM

First time I have seen the existence of such hole.... :lol::lol::lol::lol:

Whats the verdict? To unblock or to block it?

JayL 07-17-2009 01:37 PM


Originally Posted by Riketsu (Post 6080376)
First time I have seen the existence of such hole.... :lol::lol::lol::lol:

Whats the verdict? To unblock or to block it?

someone open a murnan and that will give the answer :)

Roelof 07-17-2009 02:12 PM


Originally Posted by JayL (Post 6080555)
someone open a murnan and that will give the answer :)

If he is the only one who knows? :confused:

Why create that hole and fill it up? Since it is a MAX engine originally made by Novarossi and based on their designs I can imagine Fantini has a different view on it and is this also one of the mods on his engines.

wingracer 07-17-2009 02:15 PM

Erased, never mind

wingracer 07-17-2009 02:16 PM

.

Grinder 07-17-2009 02:18 PM

[QUOTE=JayL;6080555]someone open a murnan and that will give the answer :)[/;)

EdwardN 07-17-2009 10:06 PM

Hmm, heven't been here for while.
Well, no one is answered right for nature of that hole.
I will try to help:
Look on the second picture and you will see there ie a grove right behind front bearing and this grove is pretty much hydraulic look to keep case hermetically sealed (when cranck is running oil in that griove create sort of barier. But over the time there is a lot of oil collecting and it will start leaking through the front bearing. So prevent oil leaking from front bearing, designers needs to have hole which is going from carburatortor area (which always have negative pressure) to that grove (if you remove carb you will see that end of hole). To make it manufacturable (it is not possible to make internal hole), you will need to drill the hole from front bearing through grove up to undrneath of carb. But now to make it work as sucking pump, the front end of hole needs to be blocked, so it will not suck oil/air from front bearing. Then hole is blocked on the very end of it on bearing side up to the grove. Now you have perfect chanel from carb area with negative pressure to the grove and all extra oil will be back to motor. You need to block the hole as I explaned above, or do whatever you want to.

Have fun.

wingracer 07-17-2009 10:23 PM

Interesting. Believe it or not, that actually made sense to me.

EdwardN 07-17-2009 10:36 PM

Here some pics attached from cross section of my some old design, it will help visualy understand (due to the lack of my engish) the design.
I am very suprized to see all those explanations and no one was even close.

BTW, I am out of this hobby and industry and not planning to get back any time soon. I got my self another hobby and enjoy it a lot more.

SOLOARTIST 702 07-17-2009 11:19 PM


Originally Posted by EdwardN (Post 6082171)
Hmm, heven't been here for while.
Well, no one is answered right for nature of that hole.
I will try to help:
Look on the second picture and you will see there ie a grove right behind front bearing and this grove is pretty much hydraulic look to keep case hermetically sealed (when cranck is running oil in that griove create sort of barier. But over the time there is a lot of oil collecting and it will start leaking through the front bearing. So prevent oil leaking from front bearing, designers needs to have hole which is going from carburatortor area (which always have negative pressure) to that grove (if you remove carb you will see that end of hole). To make it manufacturable (it is not possible to make internal hole), you will need to drill the hole from front bearing through grove up to undrneath of carb. But now to make it work as sucking pump, the front end of hole needs to be blocked, so it will not suck oil/air from front bearing. Then hole is blocked on the very end of it on bearing side up to the grove. Now you have perfect chanel from carb area with negative pressure to the grove and all extra oil will be back to motor. You need to block the hole as I explaned above, or do whatever you want to.

Have fun.

just wanted to say hello edward been a while how's The flying well I'm still racing take care


All times are GMT -7. It is currently 08:25 PM.

Powered By: vBulletin v3.9.3.9 Patch Level 3
Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.