Author Topic: Planning to braze a cracked rocker cover - looking for advice  (Read 780 times)

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Offline tkarahalios

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Hi folks,

I have a 1975 CB550K1 with cracked valve/rocker cover. Basically, one of the screw mounting tabs cracked off and the crack goes through part of the seal area so it leaks.
Since I can't weld aluminum, and didn't know if this is weldable due to it cutting across the seal area, I wanted to try brazing it. I found the below material on Amazon and figured I would go for it with a propane torch.

http://www.amazon.com/gp/product/B001739LJ0?psc=1&redirect=true&ref_=oh_aui_detailpage_o05_s00

The rocker cover does not contain any pressure right?
Any reason I shouldn't try this?
Also, do you think I should find someone that could weld this back together instead?
Anything else you would try to reattach this?
« Last Edit: March 11, 2016, 09:10:04 AM by tkarahalios »

Offline 70CB750

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Re: Planning to braze a cracked rocker cover - looking for advice
« Reply #1 on: March 11, 2016, 09:13:34 AM »
I would try to find a local shop or new cover.
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Offline flatlander

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Re: Planning to braze a cracked rocker cover - looking for advice
« Reply #2 on: March 11, 2016, 09:16:28 AM »
this is a good moment to get a k3 cover - the one with the pinned rocker shafts.
your k1 most probably has the old version where the rocker shafts can rotate and wear out their bearings.

Offline Stev-o

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Re: Planning to braze a cracked rocker cover - looking for advice
« Reply #3 on: March 11, 2016, 09:19:56 AM »
Personally I would replace it.

But if I did have to repair it, I would have it welded since it is aluminum.
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline strynboen

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    • http://forums.sohc4.net/index.php?PHPSESSID=7otdlhbeciv3d9n3iou2ugsh57&/topic,60973.0.html
Re: Planning to braze a cracked rocker cover - looking for advice
« Reply #4 on: March 11, 2016, 09:41:19 AM »
yes go for the 1978 k3 head vith fixed shafts..a great update...if use the old...get it tig weldet...aluminu brasing is use a soft veld material vho melts before alu does..but it is softer then aluminiun..so you dont get the full strengh of alu..
i kan not speak english/but trying!!
http://forums.sohc4.net/index.php?topic=60973.0
http://forums.sohc4.net/index.php?topic=144758.0
i hate all this v-w.... vords

Offline carnivorous chicken

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Re: Planning to braze a cracked rocker cover - looking for advice
« Reply #5 on: March 11, 2016, 11:04:00 AM »
Another vote to replace, cheap and plentiful part (and you can upgrade).

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Planning to braze a cracked rocker cover - looking for advice
« Reply #6 on: March 11, 2016, 11:04:47 AM »
Send it to member Jim French. Micro-welding with a laser.
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline Stev-o

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Re: Planning to braze a cracked rocker cover - looking for advice
« Reply #7 on: March 11, 2016, 02:54:39 PM »
Problem for him is location, I believe he is in Poland. Shipping would be very expensive.
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........