top end

Information relating to the Matchless G5 or AJS Model 8 350cc Lightweight
red_dog49
Posts: 75
Joined: Fri Mar 08, 2013 12:03 pm
Location: DERBYSHIRE UK

top end

Post by red_dog49 »

Hi all, got my carb back from mr bratby and started 2nd kick ran ok for 15mins and stopped,checked all I could but got nowhere, then observed fuel being forced out of the carb inlet !! I thought this would mean an inlet valve problem, but found so far only that one of the exhaust valve springs loose.
could this mean as I have no idea of the age of the springs, that there could be a problem with them all, also the wear I see on the rockers is that acceptable,i
any ideas from you knowledable ones would help, guess the head will have to come off now,
regards
ROB.
You do not have the required permissions to view the files attached to this post.
User avatar
dave16mct
Member
Posts: 3234
Joined: Mon Jan 01, 1990 12:00 am
Location: LANCASHIRE UK

Re: top end

Post by dave16mct »

I wouldn't worry too much about the wear on the rocker ends but that valve spring is definately wrong. The long arms should be lying flat in the tray. They could be poor pattern springs . I'd fit new springs.
Dave.
User avatar
Rob Harknett
Member
Posts: 11236
Joined: Mon Jan 01, 1990 12:00 am
Location: ESSEX UK

Re: top end

Post by Rob Harknett »

Looks like one of the springs popped out. Pull them out, inspect why it has become unseated if all looks OK, see if they refit OK.
User avatar
Janet
Member
Posts: 4147
Joined: Mon Jan 01, 1996 12:00 am
Location: EAST YORKSHIRE UK

Re: top end

Post by Janet »

Mine looked like this.
valve springs 2.JPG
You do not have the required permissions to view the files attached to this post.
Image
red_dog49
Posts: 75
Joined: Fri Mar 08, 2013 12:03 pm
Location: DERBYSHIRE UK

Re: top end

Post by red_dog49 »

HI, yes ok but would that cause fuel to exit the carb ????.
Rob.
User avatar
Janet
Member
Posts: 4147
Joined: Mon Jan 01, 1996 12:00 am
Location: EAST YORKSHIRE UK

Re: top end

Post by Janet »

Probably not. I suppose if the exhaust valve wasn't opening, the piston coming up could force whatever's in there back out via the inlet valve but the fuel should have been burnt by then. I suspect more likely a blockage having occurred stopping the fuel going into the cylinder or excess getting into the carb and finding a way out. How much fuel and where exactly is it coming out of?

Note: I know nothing about such things (being the woman who carries a small hammer for tapping the carb banjo bolt) so am only musing.
Image
Mick D
Posts: 2886
Joined: Mon Mar 24, 2014 5:44 pm
Location: Aberdeenshire

Re: top end

Post by Mick D »

Hi

What have you done to the bike since you removed the carb for refurbishment?

Regards Mick
User avatar
Duncan
Member
Posts: 2118
Joined: Thu Jul 10, 2003 1:00 am
Location: HAMPSHIRE UK

Re: top end

Post by Duncan »

red_dog49 wrote:HI, yes ok but would that cause fuel to exit the carb ????.
Rob.
Normally a sticking float/dirt on the seat of the carb fuel cut off.
User avatar
Rob Harknett
Member
Posts: 11236
Joined: Mon Jan 01, 1990 12:00 am
Location: ESSEX UK

Re: top end

Post by Rob Harknett »

Good question, What have you done also you may not get all questions answered in one go. First you need the springs sorted out and engine ready to test and sort out the carb problem. Maybe the springs were not fitted right, a leg dug in. So when the engine was run, it was easier for the spring to pop out, rather than seat properly.
User avatar
Janet
Member
Posts: 4147
Joined: Mon Jan 01, 1996 12:00 am
Location: EAST YORKSHIRE UK

Re: top end

Post by Janet »

Duncan wrote:Normally a sticking float/dirt on the seat of the carb fuel cut off.
Guess what my little hammer is for. :D
Image
Locked