Author Topic: C11 Problem  (Read 2509 times)

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Offline stev60

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Re: C11 Problem
« Reply #15 on: January 19, 2019, 09:38:05 pm »
I can see the inlet cup clearly, the exhaust is either broken or badly bent I can just see it looks to be on its side the exhaust pushrod has a slight bend, I suppose the big question where do I find one, I have a C10 rocker but they appear different.What caused it, stuck exhaust valve possibly, the exhaust pushrod has grind marks halfway down like someone has taken to it with a file

Offline timsdad

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Re: C11 Problem
« Reply #16 on: January 20, 2019, 08:57:00 am »
It seems an easy fix to me, Steve. I'd just strip the valve gear out to check damage and replace the broken parts. If the valve pushes up and down freely, lever thingy in the rocker box, I'd guess the rocker broke from stress caused by the previous disaster. A rocker should be easy to get hold of and the push rod may straighten - you don't know unless you try. Tap it and pull it gently hither and thither in a vice and check by rolling on a mirror or other flat surface. If you've got a flat, steel plate or bench then just tap the high point on that while rolling - we have to do what we have to do. That's if you can't get hold of a replacement.

I've had cams break more than once. Back in 1993 I got a puncture in my van when the back wheel ran over a bit of my camshaft that had punched a hole in the side of the engine block.


Ray
Just a motorcyclist.

Offline Ginge

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Re: C11 Problem
« Reply #17 on: January 20, 2019, 04:40:13 pm »
I might have some rocker parts that will fit.

Let me know what you need.
Ginge.

Offline stev60

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Re: C11 Problem
« Reply #18 on: January 20, 2019, 06:40:36 pm »
Thanks, Ive cleaned up the head , done a valve grind, the exhaust valve was probably the problem. get into rocker box tomorrow I will replace pushrods,Dragonfly have them  apart from the bend they have some deep pitting, cups have been knocked around. Ginge if you have a rocker that would be great, ive put a photo in. Dragonfly do replacements but I dont think mine would work as a swap     

Offline Owen

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Re: C11 Problem
« Reply #19 on: January 20, 2019, 07:10:16 pm »
Any pictures of the broken pieces?
1940 C12 (350cc)
1945 C10 & C11
1953 C10 & C11
Anyone want a B20 in need of a lot of tlc

Offline stev60

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Re: C11 Problem
« Reply #20 on: January 20, 2019, 07:15:56 pm »
I will post them when I get it out Owen, its back to work today What I can see is the cup moving and the other end not and right over to one side , which allowed the push rod to drop down past it, I cant see what caused  the grooves on the push rod about halfway down

Offline Ginge

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Re: C11 Problem
« Reply #21 on: January 20, 2019, 10:14:11 pm »
I hope nothing fell down the hole
Ginge.

Offline stev60

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Re: C11 Problem
« Reply #22 on: January 21, 2019, 06:14:08 am »
Ginge dont worry about holes they will only get you int trouble, just find me that rocker :)

Offline Ginge

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Re: C11 Problem
« Reply #23 on: January 21, 2019, 06:33:52 am »
No good my end sorry. Mine are sidevalve ones. 29-2148.  No socket on the end for the pushrod and they have a lateral kink in them.

Try norton750 on Trademe.  Murray Schwass has an old bike business in Motueka.  Bought some C10L engine case off him a while ago  Otherwise ozzyal on this site.  In Tasmania.

I’ll keep an ear to the ground. Might know of a bloke in Southland.

Ginge.

Offline stev60

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Re: C11 Problem
« Reply #24 on: January 21, 2019, 06:08:46 pm »
There are two on ebay, unsure if they will send to NZ, says for C11G and C12 but the part number matches C11 29-2285, looks the same if they wont post to NZ is there anyone who will buy and send over they are in England, our Prime minister is there  at the moment she will vouch for me :)

Offline Owen

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Re: C11 Problem
« Reply #25 on: January 21, 2019, 06:30:09 pm »
Send me a pm with the details.
I do have a couple with worn shoes that could be ready manufactured to bring the profile back?
« Last Edit: January 21, 2019, 06:33:50 pm by Owen »
1940 C12 (350cc)
1945 C10 & C11
1953 C10 & C11
Anyone want a B20 in need of a lot of tlc

Offline stev60

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Re: C11 Problem
« Reply #26 on: January 22, 2019, 02:05:46 am »
Just had time to look in, nothing broken so a bit dumb there :-[ although it appeared one end was moving but not the other. Ive put there photos in as there is obvious damage, to one rocker and damage to the sides and the part that runs on the cam(minor) . What actually holds the rocker shaft in place I can see one groove which could be for a circlip, no debris in side. cam shaft number is 29220/9 as far as I can tell is that the old or newer cam.
Steve

Offline stev60

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Re: C11 Problem
« Reply #27 on: January 22, 2019, 02:24:11 am »
Found the problem, wish I hadnt the hole for the rocker shaft in the engine casing on the crankshaft side is flogged out, seems odd that they wouldnt have put a bush in that area, anyone struck this before it really is badly worn

Offline stev60

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Re: C11 Problem
« Reply #28 on: January 22, 2019, 03:04:00 am »
The only solution I can see is to split the motor, which I would assume means removing it, bolting the two castings together and line boring then bushing both to suit the pin.
Its a bit easier to see whats happened the wear has got that bad one shaft has dropped out, altough the wear on the rocker arm I cant quite figure out Its the old story once a bit wear starts in increases rapidly, and aluminium wears quickly.

Offline Owen

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Re: C11 Problem
« Reply #29 on: January 22, 2019, 07:01:35 am »
It's quit common to see loose rocker shafts.  Depending on how loose it is, I think stev60 idea is the way to go if it's more than a few thou.
1940 C12 (350cc)
1945 C10 & C11
1953 C10 & C11
Anyone want a B20 in need of a lot of tlc