When did you last use a compression gauge?

Ray’s latest deals with picking a compression gauge. I was surprised he hasn’t used one in years. Mine? 25 years, at least, but I don’t have a shop. When did you last use one?
No Need To Break The Bank When Picking A Compression Gauge - Car Talk

3 years a go. The Mustang is due for another test. Not because it is running poorly but just curiosity.

I haven’t done a compression test in 25- 30 years, but before that I did them routinely as part of replacing the spark plugs during the yearly or biannual tune-up. It’s probably a good idea to do this test for maintenance reference purposes, since the test is neither difficult nor time consuming if spark plugs are removed anyway. So the reason I no longer do it? Just lazy I guess.

I used mine a couple months ago, on my lawn mower. I check it every year. Compression actually went up since last year. It’s the kind you have to hold in place while turning the key which is a little hard. I got it from target 50 years ago in the kit with the other items I can’t recall fir $15. Oh yeah
the remote starter cable that burned up years ago, the never used timing light, and maybe something else. Had to buy the dwell meter separate but haven’t had any points in 40 years. Everything is for sale but the the compression gauge.

Last year but sat idle for a decade before then. Checking motorcycle that has issues and wanted to rule out poor compression… BTW, the seals on the gauge had deteriorated so I had to find some new ones before I could use it.

Roseanne Roseannadanna: “it’s always something” … lol …


Only thing worse- I know I have a compression gauge- where the h#ll is it? Guaranteed to surface shortly after buying the replacement. And it’s now in a conspicuous location like gnomes or something are playing tricks… :grinning:


It was about 4 years ago when I purchased my '62 Caddy.

I “lost” a pair of pliers last winter, looked and looked for hours, this went on for at least a week. Finally found them sitting in plain sight on my living room couch, where I watch tv nearly every evening.

Stuff I have trouble finding in the drawer I paint yellow so I can see it. I have found nearly everything that was once lost, except my wood handled scratch awl. Last I used it was over a year ago in the garage working on the mower for lining holes up. I even bought another but they are plastic now. I keep looking every once in a while to no avail. I’m starting to think maybe a coon carried it away for a project.

Around 2020 during covid lock down doing a red light to bridge run (cough cough) I shifted at my normal 6K rpm but this time I lost a cylinder while doing so… oops…

Then again about a year ago while checking out a 84 Civic DX that my friend drug out of some ones back yard after sitting since sitting since 2004 IIRC…
BTW it runs like the glorious 76 HP power house that it was meant to be… lol

So about every few years or so…

People use compression testers and leak-down testers all the time today. A better question would have been “when was the last time you used a timing light?” which is something a lot of people don’t use anymore.

When did you last use a compression tester?

I last used a compression tester in January of 2021, together with a leak-down tester. That allowed me to definitively diagnose a bad head gasket and bad exhaust valve, and I then took apart the engine and had the head rebuilt. That car is still in use today.

In HS, some ‘friends’ crosswired my Plymouth 361. I start it, why is it running like this? So, of course I rev it up, one push rod through the rocker like yours, one pushrod bent, one hydraulic lifter collapsed.

Over a decade. One of my son’s friends cars. His friend wasn’t happy with the results.

Mine was just from years of shifting at 6K rpms, no running issues trust me… lol
I bought all new push rods, rockers and both shafts and installed them and right back to 6K shifts…
I do have a set of roller rockers to install one day… Not bad for an engine I built back in the mid 90;s…

Did you replace the pushrods with OEM or beefier ones?

I bought a car with botched timing belt job. I retimed it and it cranked crazy fast. Zero compression. Funny what 2 bent valves per cyl will do to compression. 5 yrs ago.

OEM stuff, Mopar’s LA engines don’t have a lot of issues with pushrods, the pushrod didn’t bend, it just simply pushed through the rocker arm… I built the engine back in the early 90"s, so it has seen a lot of 6K shifts over 25+ years, I had this engine in a different car at 1st…
I have all the parts (mostly, 99%ish) for a future upgrade, I am going to roller tip rockers with hardened shafts (already have them), but I will have to measure and order custom pushrods once the new cam (already have) is installed with new rockers and I am going to a thicker wall pushrod for less deflection then…

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