vch headgasket

Anything about Ariels
charvey
Posts: 69
Joined: Sun Nov 04, 2012 10:10 am
Contact:

vch headgasket

Postby charvey » Thu Jul 04, 2019 5:01 pm

1952 VCH alloy Head, 5 bolt is the head gasket a thin copper type or a composit type and where can I get one from Thanks Clive

charvey
Posts: 69
Joined: Sun Nov 04, 2012 10:10 am
Contact:

Re: vch headgasket

Postby charvey » Fri Jul 05, 2019 8:16 am

Hi All,
After going through old forum messages and a couple of other sources I found there is no headgasket on 5 stud alloy heads, but I found out the top hat nuts homemade needed more thread in a couple of them and shortening so as not to bottom out so I was slightly tightening on to the thread not the head any way can finish off rebuild but I cannot get my head round no headgasket just very clean metal to metal torqued to 28Lbs also smaller o rings than I fitted first time to the push rod tunnels but it works hopefully.Clive.

User avatar
Bob.Murphy
Holder of a Silver Anorak
Holder of a Silver Anorak
Posts: 882
Joined: Thu Nov 29, 2012 10:32 pm
Location: Kirkliston, on the West side of Edinburgh.
Contact:

Re: vch headgasket

Postby Bob.Murphy » Fri Jul 05, 2019 9:44 am

The head and liner have to be 'lapped' together with fine grinding paste.

I had to machine-away some alloy from the top of the barrel to get the head and liner to make contact and it all works OK now.

I wasn't sure how much clearance to leave around the liner, as the head has to be pulled down to keep the joint tight but I didn't want it bowing over the liner. I opted for about 0.010" (I could just glimpse daylight between the head and barrel before tightening).

I would be interested to hear what others think.

Hopefully you have got this all sorted now.

Bob.
My avatar shows the late Len Rich in 1970 with the bike I now have - a 1958 Ariel VH

pete.collings
Holder of a Waxed Cotton Anorak
Holder of a Waxed Cotton Anorak
Posts: 550
Joined: Fri Feb 18, 2011 10:26 am
Location: Cardiff
Contact:

Re: vch headgasket

Postby pete.collings » Fri Jul 05, 2019 11:12 am

I had a problem in the past with blowing from the head/barrel joint when mating a VHA head with a new make alloy barrel. I think the head had been lapped in too many times, as there was alloy to alloy contact between the head and barrel, rather than liner spigot to head contact.
I cured this by delaminating a composite copper head gasket used with Velocette singles, a piece of which neatly sat on top of the liner spigot.
Like Bob, I made sure there was a small gap between the alloy faces, although I cannot remember exactly what the gap was.


Return to “Ariel Talk”

Who is online

Users browsing this forum: No registered users and 49 guests