[Mgs] MGA 1500 ROCKER ARMS

[Barney Gaylord]

That being the case (which is likely correct), after shaving the 
valve stems they also need to shim the valve springs to restore 
original spring height and load.  Otherwise, cutting seats so deep as 
to run out of adjustment range is a serious infraction of good 
mechanics, for multiple reasons.  That's when it's time to bore out 
the worn seats and install new hardened steel valve seats.  Do you 
perchance have a picture of the combustion chamber showing the 
current situation of the valve heads?

Cutting seats deeper, grinding valve heads thin, shortening valve 
stems amd shimming valve springs is the sort of thing I might do to 
my own car in my home garage to avoid paying the pro shop to fix it 
right.  I hope I am past that stage of life or frugal finances (by at 
least 30 years).  The fact that you ran out of adjustment range is 
proof that the valve job was bodged, not the sort of thing you like 
paying good money for to a "professional".  Did you have a chance to 
inspect the valve seats before the valve gear was reinstalled?  Do 
you know if the seats were properly narrowed to around 0.060" or so, 
or might they be improperly wide with low surface pressure to invite 
carbon build up and future early leakage?  One bodge may well follow another.

I suppose by now there is more labor time involved, and a new head 
gasket consumed if you need to R&R the head again.  If you want to 
continue on this "patch it up" path, then slip the rocker arm aside 
and shorten the valve stem tip with a hand grinder.  That can get the 
car back on the road, until the rest of the crude valve job catches 
up with you later.  Not what you wanted to hear I suppose.

Barney Gaylord
1958 MGA with an attitude
http://MGAguru.com


At 03:22 PM 10/3/2009 -0700, Richard Ewald wrote:
>The machine shop needs to grind the stems of the valves. They cut 
>the seats too deep.
>....
>
>On Oct 3, 2009, at 7:22, "Tom Gunderson" <thgun at comporium.net> wrote:
>>I have had my 1500 head machined. New seats and guides ,.003 
>>surfaced. I put the rocker arm on and I have 2 of the rockers that 
>>will not adjust when the head is mounted on the block. The 
>>adjustment screws are all the way up and the 2 rockers are tight. 
>>The lifters and rods look like they are in the correct alinement. 
>>What can I do?
>>....