Regrinding rocker arms

I know that worn camshafts can be built up and then reground. Presumably
the same can be done with the rocker arm faces on an OHC engine. I have a
spare engine for my SO LS650 that I am rebuilding. It is generally OK but
camshaft and rockers are worn/pitted. I have a spare new camshaft so it is
either repair or replace (likely to be £££) for the rocker arms. Anyone
know of a place that can do such work? In Essex or East side of London would
be a bonus.

 

You can do it yourself if you have a gas supply and a small kiln (easily
made). I did it on some worn out rocker arms years ago - not because of
cost, but because I was pissed off at how shite they were as new and how
quickly they wore out. After case-hardening they lasted out my ownership
of the car.

If you really want somebody to do it for you, it should be easy to find
a small general engineering shop that has experience in it - there's
even a case hardening compound made for the job.
--
Dave
GS850x2 XS650 SE6a

Teach a man to fish and he and his pikey mates will have the
river cleaned out in a day.

 

My friend in the boat building and repair industry recommends
http://www.longwear-nitriding.co.uk/

I reckon you could post the parts to them

 

I had thought about that. Grind off the pitting, keeping the profile as
close as possible to original. Then heat and quench in oil. My only
concern was the possibility of making the arms themselves brittle. Anyone
else done this?

 

Oil quenching's no good - all it will do is create a too-thin skin of
hardened steel and it'll wear out in no time.

The stuff I used was called 'Carburise' or something similar. All you do
is place the pieces into the box and leave it in the kiln for several
hours. Then let it cool down naturally - the benefit of this is to
anneal the internal steel and avoid embrittlement.
--
Dave
GS850x2 XS650 SE6a

Teach a man to fish and he and his pikey mates will have the
river cleaned out in a day.

 

This is a fairly good intro to it...
http://en.wikipedia.org/wiki/Case_hardening
--
Dave
GS850x2 XS650 SE6a

Teach a man to fish and he and his pikey mates will have the
river cleaned out in a day.

 

Kiln? Strangely, I do not appear to have a kiln. It looks like back to
finding someone to do it.

 

You don't need a kiln. Just bury the rockers in carburising powder in
an old baking tin, stick the tin in your nice shiny kitchen oven and
bake for the required amount of time. Leave them to cool slowly and
the job's done.

I used to have charts showing cure times etc but I'm sure everything
is available on the web.

 

As Andy says, you don't actually need a kiln, but to avoid marital
distress and domestic murder, you can either use a discarded oven
(plenty around if you know where to look) or make a small kiln up from
refractory bricks.

Shit, the commercial kiln I used was basically just a big hearth of ref
bricks with a lid and a huge gas burner - dead simple, all you do is
scale it down.
--
Dave
GS850x2 XS650 SE6a

Teach a man to fish and he and his pikey mates will have the
river cleaned out in a day.

 

That sounds like a plan. Thanks for the info.

 

No problem there - SWMBO hates cooking (I'm the cook in the family) and
probably won't care what I do with the oven. I think I will give it a try.

 

It will stink, though. A heavy dreadful smell of doom, gloom and burnt
nadgery bits, such as only a cooking mixture of carbonaceous oily shit
can give off.
--
Dave
GS850x2 XS650 SE6a

Teach a man to fish and he and his pikey mates will have the
river cleaned out in a day.

 

According to the instructions for this kind of stuff it needs a temperature
of 800C - more than twice what the oven can deliver.