Grind the edgesoff in my Zenoah crankcase?

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waqr

waqr

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I`m going to put this kit on next week :

http://www.oneillbrothers.com/rccar/itemdescription/z26ccbbk_ported_machined_wc.htm

Do I have to do something to my Zenoah crankcase in order to make it fit properly? I seem to remember that someone mentioned something about "having to grind the edges off the crankcase in order to make this kit fit, is this correct? If so, how do I do this grinding properly? See my crankcase below:

2hgbcli.webp
 
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I would have thought if mods were needed they would have been mentioned on the O'Neil site...
 
here waqr.

hey waqr

no you need to do nothing to make this kit fit,its same as mine(great kit)

if you want you can do this below

what you need to do is grind down the little deep notches there at the top of the cylinder case where head fits on,you would need a dremal tool and be very carefull,i will try and sent you on a detailed link here of the job in detail ok.

this was a boat engine like our engines ported,watch the way the case was machined as you scrool down along the page,pay attention to the way the case was done,you get the idea of what/how you do it..

hope this helps.

i personally think this modification has little or no worth while gains.

http://www.modelgasboats.com/Magazine_Content/Tech_Articles/Engine_Porting.html
 
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I think..and don't quote me on this, but the little "tab" (in your pic...on your crankcase, top right side of it..the little rectangular "tab") might need to be ground off.
I got this....http://www.davesmotors.com/s.nl/c.885035/n.1/it.A/id.4756/.f
and in the instructions, as i read it, "if you are putting this top end on any Zenoah based cases, there may possibly be one little modifaction you will need to do. After you pull off the cylinder, examine the transfer bowl of the clutch side case half. Below the cylinder gasket surface, you will see a little nub that is cast onto the case......if the nub is there, it has to be removed, so the larger piston will not hit it as the piston approaches the bottom of its travel"
Hope this answers your question...mind you i have a different top end..but im assuming that it is the "same"
 
Kwakr said:
I think..and don't quote me on this, but the little "tab" (in your pic...on your crankcase, top right side of it..the little rectangular "tab") might need to be ground off.
I got this....http://www.davesmotors.com/s.nl/c.885035/n.1/it.A/id.4756/.f
and in the instructions, as i read it, "if you are putting this top end on any Zenoah based cases, there may possibly be one little modifaction you will need to do. After you pull off the cylinder, examine the transfer bowl of the clutch side case half. Below the cylinder gasket surface, you will see a little nub that is cast onto the case......if the nub is there, it has to be removed, so the larger piston will not hit it as the piston approaches the bottom of its travel"
Hope this answers your question...mind you i have a different top end..but im assuming that it is the "same"
Click to expand...


Ok...thats what I thought :sleep: But what do they mean with bigger piston. The piston size is the same as original, the only thing different is the 2mm longer crank, right?
 
dc2 man said:
hey waqr

no you need to do nothing to make this kit fit,its same as mine(great kit)

if you want you can do this below

what you need to do is grind down the little deep notches there at the top of the cylinder case where head fits on,you would need a dremal tool and be very carefull,i will try and sent you on a detailed link here of the job in detail ok.

this was a boat engine like our engines ported,watch the way the case was machined as you scrool down along the page,pay attention to the way the case was done,you get the idea of what/how you do it..

hope this helps.

i personally think this modification has little or no worth while gains.

http://www.modelgasboats.com/Magazine_Content/Tech_Articles/Engine_Porting.html
Click to expand...

But didn`t you mention something about having to grind something off your Zenoah crankcase when putting the O`neill brothers kit on? Wasn`t that why you used the CY crankcase instead? So you don`t think the little tap in the right corner of the crankcase will interfer withe the kit?
 
here's my cy case, you can see how much better the cy is port matched, I only had to touch up one corner for my 28.5 race ported head...you might want to dremel some material off in the corners to smooth out the airflow into the transfer ports
you will definitely have to grind off the tab
dsc00084rs1.jpg
 
Ok.... so I will try to do some grinding this weekend then :) So if I grind the tap off and smoth the other corners off a bit, will more or less all top end kits (ported and non ported) fit my crankcase?
 
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