Morris Minor Owners Club

Before I plumb for some piece of fragile tat that breaks when I remove it from the box, can someone recommend a good compression tester please?
Thanks.

This is the make and type of compression tester I use and it has given good service over many years.
https://www.ebay.co.uk/itm/326785013031 ... R6TeuPfgZg

I have the Draper 35880 which is very good and has a hard case to keep it in. It is a tool that I use so infrequently that it would have made more sense to borrow one really.

Stephen

Like Phil, I have a Gunson's compression tester, similar to that linked. However, it's very old with the scale in lbf/in2, not bar. Although rarely used it has done good service over the years. I did use it aout 6 months ago to check my Minor's cylinder compressions, all four around 160/165p.s.i..

It really does not matter if the reading is read as lb/sq in or bar - what you are looking for is a good pressure and even readings across all cylinders.
12 bar/168lb.sq in is a good reading.

Many thanks.
What it should read was my next question.
I don't know why but I like the look of the Draper unit and have had good service from other Draper tools.
Onwards and upwards.

"It really does not matter if the reading is read as lb/sq in or bar" It does to me Phil, I'm old school
It wouldn't surprise me if my old gauge is better quality than the modern equivalent - even Gunson's (made in Taiwan).

I have ordered the Draper 35885 which covers 4 sizes of thread.
It will as suggested by Stephen probably be used once in a blue moon, I could rent it out to the neighbours of course.
I have within a stones throw a TVR an MGA an E type a Mini a MK1 landy and a few specials too.
Thanks again.

Mervin
Being old schools does not make the compression reading any higher. It is what it is.
Phil

Checking back through my maintenance log (for the Minor I still run), I found this entry from 48 years ago. It shows that measuring every 2-4k miles can tell a useful story. In this case, new piston rings, please! The floating dots at 57.2k miles show that - when fitted - the new rings brought them all up to 132 psi (+/- 3psi). It had an 803cc in those days, doing 11,000 miles/annum. Nowadays, and with it's recently installed (1979 ) 1098, it's more like 1000 mpa.

Wonder why 2 was so low??

John ;-)

Thanks for the chart, that's interesting.
Coloured lines like that just highlight my colour blindness, but I get the gist.
I think I should do something similar when I get my tester delivered.

Sleeper wrote: ↑Thu Dec 11, 2025 5:06 am Wonder why 2 was so low??

John ;-)

My 48 year old notes show I replaced the middle 3 of its 5 rings.
Incidentally I sold that engine to a Southampton student in 1979. Has anyone still got it (No. 221137)?