What Compression tester

[bofh]

Hi folks, I'm sure I read a thread somewhere on here regarding what compression tester should be used on saws, but I can't find it now I need it

 

So could someone advise me what type/brand I should be looking at. Or link me to the thread.

 

Cheers

[GardenKit]

There was a thread a while ago. Basically you need an automotive type tester which will read up to 300psi, although your operating range will be 50 to 180psi generally.

 

It needs to be a screw in one, not a push fit.

 

Most 2 strokes used 14mm plugs until the last few years when a few 10mm plugs have appeared, so make sure the tester has a 10mm adapter, many do not.

 

I have two currently. One is an old Draper and the other a new Sealey CT955 V2

[spudulike]

The Gunson Hi Gauge is suitable but it keeps blowing valves on my 357 - it does run at 200psi though:001_rolleyes:

 

You dabbling again Bob??

[bofh]

Thanks guys, I'll get looking for one :-)

[JAMIE1]

For two stroke engines you need one with a schrader valve in the end (exactly like the valve in a car tyre) you cant use 4 stroke compression testers on 2 stroke machines.

[Adamam]

The cheapo Gunson one is fine as far as I can tell (tested against a couple other random alternatives).

 

It's not like it's a mission-critical piece of kit in terms of absolute accuracy...

 

...more about online super-heroes banging-on about their amazing compression!!

 

[spudulike]

Beware some of the car types - the schrader valve in the tip of the compression gauge MUST have a low opening pressure, if it doesnt and is a typical tyre valve type, it will only be suitable for large vehicle engines and not saws.

 

The Gunson one does work as it should, some of the ebay ones don't

[bofh]

Well I nipped into a certain high street car centre and got myself this

 

 

I shall have a tinker with it tomorrow I hope.

 

Cheers for the advice

[spudulike]

  bofh said:

Well I nipped into a certain high street car centre and got myself this

 

 

I shall have a tinker with it tomorrow I hope.

 

Cheers for the advice

 

Thats the one - lok for 150psi on a well running engine, 175psi on a saw just run in and 200+psi on a modded saw!

[Maico490]

I have one of those and have found it to be very good and it agrees with the gauge on the compressor.A while back I hadn't used it for several months and as in the picture I had stored the bigger adaptor on the end.Managed to convince myself I had lost the adaptor for "standard" sized plugs and wasted three hours looking for it and searching the internet for a replacement.Bit of a DOH moment when I realised what had happened !!!!!!!!!