Exhaust Valve Guide Eaten!

pictures (or stories) of hideous injuries sustained by your ariel
User avatar
robjameson
Holder of a Silver Anorak
Holder of a Silver Anorak
Posts: 651
Joined: Mon Feb 28, 2011 11:36 am
Location: Derby, UK
Contact:

Exhaust Valve Guide Eaten!

Postby robjameson » Sat Nov 09, 2013 10:36 pm

While refitting my rocker boxes having re-torqued my head bolts today, one of the threads pulled. Thought i'd better remove the head in order to get a helicoil put in.

On removing the silencer, there was a suspicious rattle, and on upending it some bits fell out, which looked suspiciously like a valve guide.

Off with the head and exhaust valve out and this is what I found.

I suspect that the issue has been caused by a problem I had with timing earlier in the year, and I have overheated the guide, mixed with what looks like a slightly bent valve.

Good job I bought a spare VH last weekend I suppose!
Attachments
DSC01276.JPG
DSC01275.JPG
Rob Jameson
AOMCC Member Number 4068
1957 Ariel VH
2016 Honda CBR600RR

User avatar
admin
Holder of a Silver Anorak
Holder of a Silver Anorak
Posts: 712
Joined: Thu Feb 10, 2011 1:22 pm
Contact:

Re: Exhaust Valve Guide Eaten!

Postby admin » Sat Nov 09, 2013 10:42 pm

was that Mr MItchells VH, perchance ?
The one, that a certain Paul Jamesone (any relation ? :o ), warned me off ...
John Nash
Administrator
webmaster@arielownersmcc.co.uk

User avatar
robjameson
Holder of a Silver Anorak
Holder of a Silver Anorak
Posts: 651
Joined: Mon Feb 28, 2011 11:36 am
Location: Derby, UK
Contact:

Re: Exhaust Valve Guide Eaten!

Postby robjameson » Sat Nov 09, 2013 11:13 pm

It certainly was John's VH!

Dad warned me off it as well, but being quite persistent I went to have a look with him and it was actually very good in the flesh, just goes to show that you need to have a look at these things and not just go off the photos.

It is a 1955 machine but at some point has had a replacement frame from the factory, so has fittings for half and full width hubs. Needs work but one day will be a nice enough bike.
Rob Jameson
AOMCC Member Number 4068
1957 Ariel VH
2016 Honda CBR600RR

nevhunter
Holder of a Golden Anorak
Holder of a Golden Anorak
Posts: 2878
Joined: Tue May 10, 2011 9:42 am
Location: Victoria.. Australia.
Contact:

Re: Exhaust Valve Guide Eaten!

Postby nevhunter » Sun Nov 10, 2013 12:47 am

What sort of material is it? The alloy heads normally run bronze guides don't they? Nev

User avatar
andrew.chapman
Holder of a Nylon Anorak
Holder of a Nylon Anorak
Posts: 128
Joined: Sat May 07, 2011 6:19 pm
Contact:

Re: Exhaust Valve Guide Eaten!

Postby andrew.chapman » Thu Aug 14, 2014 10:54 am

If the valve is bent then that is probably the cause of the broken guide. I would be looking for the cause of the valve/piston contact - incorrect valve timing, over-revving or a sticking valve are most likely.
AndyC
http://www.foxwoodmotorcyclerandr.co.uk
BMW K1300GT 2009, BMW K1200RS 2002, Ariel VH 1954, Sunbeam S8 1952

User avatar
robjameson
Holder of a Silver Anorak
Holder of a Silver Anorak
Posts: 651
Joined: Mon Feb 28, 2011 11:36 am
Location: Derby, UK
Contact:

Re: Exhaust Valve Guide Eaten!

Postby robjameson » Wed Oct 29, 2014 9:27 pm

Turns out it wasn't a bent valve, it was caused by the guide coming loose and burrowing its way down the soft alloy head, and then effectively splaying out the valve guide at the base of the valve stem.

All got repaired by S.E.P Kegworth early this year and no issues since.
Rob Jameson
AOMCC Member Number 4068
1957 Ariel VH
2016 Honda CBR600RR


Return to “A Bad thing happened to my Ariel”

Who is online

Users browsing this forum: No registered users and 1 guest