Compression tester: recommendations?

[aprophet2]

I have a cheap Harbor Freight tester that shows everything to be damn near 1/2 the compression of what I know it to be (yes, I know how to use it. throttle open, many pulls, etc). I'm sick of doing the math and just want one that works. I did a quick Amazon search and most of them look like the same exact thing I already have! Does anybody have an accurate one that they like for small engines? Let me know...Thanks

 

[Andyshine77]

Snap on

 

[CausticUC]

There are many out there, really depends in the resolution you are looking for which comes down the the gauge itself. Maybe you just need to replace your gauge dial (I am guessing it is analog).

They are simple to make as well if you dont need anything fancy: Good gauge, pipe, tire valve, and a rubber plug or spark plug adapter. This is the way the older ones were made.

Only downsides of building it that way is you need a screwdriver or something to release the pressure. It will also only show you max compression; for bleed down you would remove the valve core.

There are fancier analog gauges that also have a pressure release.

 

[Vintage Engine Repairs]

Anything that is good quality. Spend around $100 USD and ensure there is a shrader valve on the threaded insert and also one on the dial connector too. I brought a cheap one before taking it right back and sourcing a Kincrome one, haven’t looked back.

 

[MacAttack]

I have a Craftsman tester with accessories that works nice.

 

[jp233]

yeah I think mine is Craftsman, about 15 years old. But I also have one which is probably 70's or 80's, it still works fine too just the hose is getting a little sad

 

[SteveSr]

You need one that is specifically designed to handle the small combustion chamber in small engines. It needs to have a low pressure (white) Schrader valve in the tip of the adapter. After considerable searching here is what I came up with...

 

[Deleted member 117362]

You need one that is specifically designed to handle the small combustion chamber in small engines. It needs to have a low pressure (white) Schrader valve in the tip of the adapter. After considerable searching here is what I came up with...

View attachment 842471View attachment 842472

Nice. They rank in top 5 best of 2020.

 

[ammoaddict]

You need one that is specifically designed to handle the small combustion chamber in small engines. It needs to have a low pressure (white) Schrader valve in the tip of the adapter. After considerable searching here is what I came up with...

View attachment 842471View attachment 842472

That's the one I have. I was getting ready to post up a link.

https://www.amazon.com/dp/B0002WSC0G/ref=cm_sw_r_cp_apa_i_RwIdFb3HE660E
Sent from my moto g(7) power using Tapatalk

 

[lone wolf]

Snap on

Yup!

 

[brad ruch]

I use a Mac tools CT70.comes with spare valves and Orings.

Sent from my Pixel 2 XL using Tapatalk

 

[CausticUC]

I have a few, but I use my allstate the most, looks like this one:

Simple, fast.

 

[RanchDad]

I use a Mac tools CT70.comes with spare valves and Orings.

Sent from my Pixel 2 XL using Tapatalk

I second this ^^. I’ve had mine for years and it’s been flawless:

 

[Andyshine77]

I have found the testers that use a regular O-ring tends tend to blow out around 180psi, the flat washer on the Snap-on holds! and the lines are nice and strong too. myself and a few others went through a bunch of different branded testers before we all settled on the Sbap-on, though the Mac looks better than most of the others. IMHO if you want one tester that lasts and gives repeatable readings grab the Snap-on, not cheap though.

 

[PV Hiker]

I have found the testers that use a regular O-ring tends tend to blow out around 180psi, the flat washer on the Snap-on holds! and the lines are nice and strong too. myself and a few others went through a bunch of different branded testers before we all settled on the Sbap-on, though the Mac looks better than most of the others. IMHO if you want one a tester that lasts and gives repeatable readings grab the Snap-on, not cheap though.

How much is the Snap-On? And do you still need to find the truck visiting shops to buy?

 

[Andyshine77]

You can find them used for about $150 or new for $230-$250 no not cheap. I got buy with cheaper gauges, but they always seemed to go out of calibration or totally stop working all together, so I broke down and picked up a really nice used Snap-on from Ebay.

 

[Vintage Engine Repairs]

It’s a great tool to have. I was told that my rings were shot and right on the verge of no longer usable, however a good quality compression tester doesn’t lie. They are showing 150 PSI and I know this gauge is accurate.

My junk 180 showed 110 psi
My new 180 showed 170 psi
My rebuild 260 showed 190 psi
Now this 034 with old piston and rings but good shape shows 150psi.



exactly where I’d expect them to be