head/cylinder replacement?

Hi all

In furthere stripping of my 75, I found that one cylinder has not been
sitting right on the head because one can tell that this is where it must
have lost compression. When I did a compression test, I found that cylinder
lacking so now it makes perfect sense. The mounting nuts/studs withstood the
mounting torque, so it wasn't due to a loose mounting nut.

My question is would it be best to just get the head machined or replaced?
I've seen original German heads and cylinders for sale and was wondering if
buying them is just a better option since machining comes at a cost, not
everyone can do VWAC heads and most of the time you have to ship the
hardware to get it done. Pricewise, it is almost a wash and there's nothing
like shiny new hardware. Does this make sense or is it best to stick with
the original equipment in this case?

Also, if I don't replace the cylinders, since I got the cylinders/pistons
off is it just a good practice to replace the rings? They look good but it
would be easy to do now, right?

Thanks, guys!
Remco

remco wrote:

> Hi all
>
> In furthere stripping of my 75, I found that one cylinder has not been
> sitting right on the head because one can tell that this is where it must
> have lost compression. When I did a compression test, I found that cylinder
> lacking so now it makes perfect sense. The mounting nuts/studs withstood the
> mounting torque, so it wasn't due to a loose mounting nut.
>
> My question is would it be best to just get the head machined or replaced?
> I've seen original German heads and cylinders for sale and was wondering if
> buying them is just a better option since machining comes at a cost, not
> everyone can do VWAC heads and most of the time you have to ship the
> hardware to get it done. Pricewise, it is almost a wash and there's nothing
> like shiny new hardware. Does this make sense or is it best to stick with
> the original equipment in this case?
>
> Also, if I don't replace the cylinders, since I got the cylinders/pistons
> off is it just a good practice to replace the rings? They look good but it
> would be easy to do now, right?
>
> Thanks, guys!
> Remco
>
>
I can't decide for you what to do, but this info:
'75 FI heads are different from the earlier carb heads -
valve size for one.
I would carefully inspect that head for cracks, especially
around the exh seat and plug hole.
If you have to replace, do both sides.

If you re-ring, the cylinders should be honed.
Most guys won't bother re-using old cylinders;
if budget is tight, go for it...

Speedy Jim
http://www.nls.net/mp/volks/

"Speedy Jim" > wrote in message
...
> I can't decide for you what to do, but this info:
> '75 FI heads are different from the earlier carb heads -
> valve size for one.
> I would carefully inspect that head for cracks, especially
> around the exh seat and plug hole.
> If you have to replace, do both sides.
>
> If you re-ring, the cylinders should be honed.
> Most guys won't bother re-using old cylinders;
> if budget is tight, go for it...
>

I heated up the head a little and think I found something that looks like a
crack near the plug.
Thanks, Jim, for the sanity check -- replacement was the direction I was
leaning towards.

Also, after cleaning and looking at the rocker arm a little closer, I see
blobs of small welds in some spots. One appears to have been ground down but
not all the way, almost like it is a balancing method.
It actually looks original and does not appear to be a fix -- what is this
for? Is this some sort of way of balancing the rocker arm? (didn't think
that was needed)

Remco

remco wrote:
> "Speedy Jim" > wrote in message
> ...
>
>> I can't decide for you what to do, but this info:
>> '75 FI heads are different from the earlier carb heads -
>> valve size for one.
>> I would carefully inspect that head for cracks, especially
>>around the exh seat and plug hole.
>>If you have to replace, do both sides.
>>
>> If you re-ring, the cylinders should be honed.
>> Most guys won't bother re-using old cylinders;
>> if budget is tight, go for it...
>>
>
>
> I heated up the head a little and think I found something that looks like a
> crack near the plug.
> Thanks, Jim, for the sanity check -- replacement was the direction I was
> leaning towards.
>
> Also, after cleaning and looking at the rocker arm a little closer, I see
> blobs of small welds in some spots. One appears to have been ground down but
> not all the way, almost like it is a balancing method.
> It actually looks original and does not appear to be a fix -- what is this
> for? Is this some sort of way of balancing the rocker arm? (didn't think
> that was needed)
>
> Remco

IIRC that was merely to close off a drilling for an oil passage.
Nothing to worry about...

Speedy Jim
http://www.nls.net/mp/volks/