73 MGB - remove #1piston without removing engine?

[cosmo]

Is it possible to remove the number one piston without pulling the
engine? This is a USA model if it makes any difference.
I had blue smoke filling the engine compartment, rough idle and low
power. The back 3 cylinders were all 155lbs but the front one was 90.
It came up 5 lbs with a spoon of oil added. Re-torquing the head
didn't change anything. Head removal didn't show any problems with the
gasket. The cylinder isn't scored. Inspecting the valves faces while
still installed in the head show they aren't carboned or dirty or
distorted or worn looking. Any ideas? Thank you for your time.

[Dan Beck]

Hello,

I certainly would think you could pull the head again, take the oil pan off,
loosen the connecting rod journal bolts, and pop the piston/connecting rod
assembly out the top. After all, when you install a piston the connecting
rod is already attached, and you use your piston ring compressor tool to
slide the piston back in.

Certainly would not be a small job, however. You may want to mic the
cylinder walls to make sure you don't need an overbore. I think an overbore
would necessitate pulling the engine...

Regards,
Dan

"cosmo" <sd...@dfsdf.com> wrote in message
news:1hkk64plf97mquk4r...@4ax.com...

[Dano58]

You can, but the problem is, you need to remove the oil pan and the
front couple of bolts are blocked by the crossmember.... I have heard
of loosening the front engine mounts and jacking up the engine to get
to those bolts, but depending on the year of your car it may be
difficult to loosen the driver's side (LHD) mount if the steering
shaft goes through it (i.e., rubber bumper models).

Dan D
'76 B
'65 B
Central NJ USA

[Dano58]

On Jul 1, 12:03 pm, cosmo <s...@dfsdf.com> wrote:

Oh, just saw the subject - with a '73, you may be able to loosen that
driver's side mount. On my '76, you actually have to remove the entire
steering rack assembly to replace the engine mount!

[Kevin Hall]

The cross member is removeable.
KH
"Dano58" <dan.d...@gmail.com> wrote in message
news:d13ecb87-973b-4479...@r66g2000hsg.googlegroups.com...

[Dan Beck]

Hmm,

another thought...

Seeing how you only gained 5 lbs wet it makes me wonder if your valve guides
are bad, and maybe losing compression because of bad valves. Find yourself
one of those pressure hoses with the spark plug adaptor, used for
pressurizing a cylinder in order to change valve springs with the head still
on. Connect this hose to an air compressor, set the #1 piston to TDC, and
pressurize the cylinder to 100 psi. Listen to the tailpipe (bad exhaust
valve), open up the throttle and listen to the carburetor air inlet (bad
intake valve), and take off the radiator cap and see if you have gas leaking
into the coolant (leaky head gasket).

Regards,
Dan

"cosmo" <sd...@dfsdf.com> wrote in message
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