Subject: Ring JOB
Date: Monday,November 20,1995 3:56PM
I am a first time MGB owner who is attempting to "follow the book" and
replace the piston rings in my '79 MGB roadster. I have a simple question,
but feel compelled to provide a detailed background.
I changed the oil and then set out to adjust the carb. I heard a "blopp"
and out of my tail pipe came BILLOWING BLACK, BLACK SMOKE. Enough smoke to
make me hack and cough. After shutting down the engine and visually
inspecting for damage under the hood and underneath, I attempted to start
the car again. Guess what. I killed the battery trying so many times.
Pulling the plugs showed that the plugs were coated with black, wet oil.
1. Have I blown the Oil rings on one (or more) of my pistons??
Perhaps... Maybe even poked a hole in one. Do a compression test. Maybe this
is just some emission do hickey problem which is putting oil from the pcv
valve into your carb. ***Coulds you have put too much oil in there? Check
the oil level.***
2. Now that I have started to pull the head, I want to replace all the
rings for all four cylinders. Moss sells them in a kit, but what is the
difference between the ring kits which say:
a. std. (I assume this means standard)
Well, unless your engine was just rebuilt like 5K ago, you don't generally
just replace the rings. You will need to have the cylinders checked and they
will probably need some boring to get rid of scoring and ovalling. The
amount that they have to cut determines which pistons and rings you will be
buying. The number refers to the amount oversized. If you put oversized
rings in a std piston you will get a bit of piston slap and this is not too
good. Generally, to do it right, your looking at quite a bit o money for a
rebuild. Please recharge your batery and do a compression test to determine
what actually happened. check out the possibilituies listed under 1 simple
things tend to be cheaper and more frequently the cause of the problem
3. Should I wait to measure the cylinder walls before phoning in my
order to Moss for the standard rings?
4. Should I also order new cylinder liners?
You realize that your going to need a good machine shop for this stuff...
Tim Moses USNA '86