Originally Posted by barry123400

Actually we do have and use a method of establishing the quantity of blowby. Removing one end of the breather tube and obstructing it totally with your finger while timing the seconds till engine quits. It is a very useful way of guestamating the remaining life left in these engines. The actual time to exceed is something like 10-12 seconds before engine dies. The engine quits because the built up back pressure shuts off the injection pump. I will not consider an engine with a time of less than 10 seconds myself but the true range of times is buried in the archives somewhere. Of course perform the test with the engine up to operating temp. I also would be very interested in the time a freshly rebuilt engine just broken in gives as have missed the mentioning of it or perhaps has never been posted to my knowledge. Maroon this is about as practical as it gets as it is almost absolute and I prefer it to the oil cap test even though it is also a good test.. Neither gives actual volume but both indicate to some extent reality with the tube test perhaps a little less subjective as I can describe the run length better than an exact description of how much the oil cap is moving. The common expression is dancing by the way. I want all my 123s to be 10 second or better cars. Twelve seconds is a lot better for example. Well have to go down to the workshop and turn out some loaded oil caps. Need to melt and conceal about a half pound of lead to each one..Watch out for loaded oil caps coming to an ebay auction near you. I thought I had seen it all in life. Then ebay surfaced. I can almost a visualise it now. Good for a million miles and the oil cap does not even move when loosened.