Crack on valve seat

Helpful information and requests for assitance and advice
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chtijr
Posts: 8
Joined: Mon Jan 27, 2020 12:38 am
Location: France Nord/Pas de Calais

Crack on valve seat

Post by chtijr »

Hello everyboby

Is it serious doctor ??

https://www.dropbox.com/s/juinej321k6xu ... 0.JPG?dl=0

Thank you

JR
Mick D
Posts: 2886
Joined: Mon Mar 24, 2014 5:44 pm
Location: Aberdeenshire

Re: Crack on valve seat

Post by Mick D »

Needs a transplant
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1608
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Posts: 2493
Joined: Mon Oct 05, 2009 1:00 am
Location: ESSEX UK

Re: Crack on valve seat

Post by 1608 »

Lucky its not an iron head. Loose or cracked seats on alloy heads are, dare I say, not uncommon.
chtijr
Posts: 8
Joined: Mon Jan 27, 2020 12:38 am
Location: France Nord/Pas de Calais

Re: Crack on valve seat

Post by chtijr »

1608 wrote:Lucky its not an iron head. Loose or cracked seats on alloy heads are, dare I say, not uncommon.
Thank you .

I dont know how many kilometers the bike have done with this existing crack in the eighties .

Perhaps a lot . The bike was not stopped for this problem but for an other .


However, if i put some acetone or gasoline with the only weight of the valve
ther is no leakage after 10 minutes .

Do you think there is a risk of more severe damage in case of i run the bike like this ?

Many thanks for your interest .

JR
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GOLDSTAR
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Joined: Thu Sep 11, 2003 1:00 am
Location: KENT UK

Re: Crack on valve seat

Post by GOLDSTAR »

get it replaced, even if only for peace of mind, kind regards
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1608
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Joined: Mon Oct 05, 2009 1:00 am
Location: ESSEX UK

Re: Crack on valve seat

Post by 1608 »

As already said, get it changed for peace of mind. Especially as you have gone to the trouble of stripping the engine so far. There is a good chance that the seat might become looser and come adrift.
Also, when the head gets hot it probably already does come loose which will make it even sloppier in the head.etc etc.
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