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Re: Loss of compression
Posted: Tue Oct 31, 2017 10:55 am
by Rob Harknett
Bruno wrote:Hello,
An unexpected delay in rectifying the problems with my G3. I managed to shred the ends of my left hand thumb and index finger on a circular bench saw - very lucky to still have them and on the mend, but I've been 'digitally challenged' for the couple of weeks.
I will shortly resume clean up on the exhaust valve and get the top end back together. It is now moving nice and smoothly in the guide since removing the deposits. I think the build up may be related to the bike being run very rich by the previous owner - when I got the motorcycle it was running really badly, mainly due to the carb set up being far out.
Anyhow, I'll give it a go and report back in due course ... hope to catch a couple of warmer days for runs before the proper Scottish winter sets in.
Cheers, Bruno
Opps 50 years a wood machinist and never a scratch. Most of the time as a machine setter / supervisor. I had to make sure machines were properly guarded and operator made aware of all dangers. Then some fool cut the tip off his little finger. Guy said, there was a little gap I thought my little finger could go under, so I tested it. You don't expect anyone to do that with the machine running. Eventually we had to sack him as he was a danger to others.
Re: Loss of compression
Posted: Wed Nov 01, 2017 8:32 pm
by Bruno
Hello Rob,
Sounds like he might have been a relative of mine!
No excuses ... I broke every basic safety measure and was very lucky to just damage a couple of digits which are on the mend.
I can even get my motorcycle gloves on now.
Cheers, Bruno
Re: Loss of compression
Posted: Fri Nov 03, 2017 6:20 pm
by g80csp11
Bruno , if t turns out it was not the valve seat , send me you address so I can post you the
£1 I owe you !
Re: Loss of compression
Posted: Sat Nov 04, 2017 9:42 am
by Janet
g80csp11 wrote:Bruno , if t turns out it was not the valve seat turning , send me you address so I can post you the
£1 I owe you !
Corrected for you.
Re: Loss of compression
Posted: Sat Nov 04, 2017 11:43 am
by g80csp11
only to happy to be proved wrong and corrected . always pay my dues eventually !
Re: Loss of compression
Posted: Fri Apr 06, 2018 9:25 pm
by Bruno
Hello,
I'm at last in the process of putting the top end of my G3 back together. However, I've discovered that 2 of the 3 different washers around the rubber gasket at the top of the push rod covers are missing and that the old rubber gaskets don't seem to be rubber at all - it's a hard, brittle black material like bakelite?
Probably explains why I've experienced some oil leaks around the push rod covers ever since I bought the machine.
Is this just a 'bodge' by a previous owner or were these gaskets made of this sort of material in the past? I've bought new rubber gaskets and sets of all 3 washers for the rebuild anyhow.
Cheers, Bruno
Re: Loss of compression
Posted: Fri Apr 06, 2018 9:56 pm
by SPRIDDLER
It's not a bodge. The rubber collars do turn to Bakelite brittleness over time and leak.
This was answered on the Forum extensively a week ago.
Here's the link....
http://www.jampot.com/forum/viewtopic.p ... 5&start=20
Re: Loss of compression
Posted: Sat Apr 07, 2018 11:30 am
by Bruno
Thanks for this link Spriddler.
I've already received the replacement rubber gaskets, so I'll just fit them for now - but great insights into alternative leak free options.
Cheers, Bruno
Re: Loss of compression
Posted: Tue Apr 17, 2018 11:00 am
by Bruno
Hello,
Finally ... put the top end back together last night, good compression and started up 2nd kick. Nice to hear that steady, deep resonating thump again after several months!
Turns out that the head needed a thorough decoke and the both inlet & exhaust valves re-ground - there was a heavy build up of carbon deposits around both valves which was preventing them from seating properly and the tappet stems were a bit tight in the guides and needed some light cleaning to free them up again. Everything else was sound, so pretty straight forward in the end.
Just really glad to be back on the road and intending to join the Cairn 'O Mount run staged by the VMCC in Aberdeenshire next month ... maybe even get some decent weather?
Cheers, Bruno
Re: Loss of compression
Posted: Tue Apr 17, 2018 3:23 pm
by Janet
Who won the £1 (she asks, hopefully)?