Gunson Gas Analyzer

An alchemy of sparks, copper wire and earth

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kentishvanman
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Gunson Gas Analyzer

Post by kentishvanman »

HI,

Has anyone used or have any thoughts/comments on this product?

Might buy one.

Thanks
1987/8 Autosleeper, 1.9dg (Automatic) hightop. Petrol/ LPG

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937carrera
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Re: Gunson Gas Analyzer

Post by 937carrera »

I have one & use it for my classics.

It takes a bit of time (5-10 minutes) to allow it to settle down & calibrate properly but works well for setting idle mixture on carbs. Verrry fine tweaks on the calibration dial when setting up, but you'll soon get the hang of it

Don't expect to use it for reading gas composition at higher revs

With our rear engines it's much easier to run it off a spare battery.
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

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itchyfeet
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Re: Gunson Gas Analyzer

Post by itchyfeet »

The one I have only does co but I use it to check the co before MOTs
1988 DG WBX LPG Tin Top
1989 DJ digijet WBX Holdsworth Villa 3 Pop Top
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itchyfeet
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Re: Gunson Gas Analyzer

Post by itchyfeet »

937carrera wrote:
With our rear engines it's much easier to run it off a spare battery.

I clip onto the alternator on a late van but not easy on an early van
1988 DG WBX LPG Tin Top
1989 DJ digijet WBX Holdsworth Villa 3 Pop Top
itchylinks

kentishvanman
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Re: Gunson Gas Analyzer

Post by kentishvanman »

Hi,
itchyfeet wrote:The one I have only does co but I use it to check the co before MOTs

As you may have seen in the Alternative Fuels section I am going to fit a new lpg regulator.
Tinley Tech reckon you can set them up quite well by ear but there is not much point in arriving for an MoT and finding that my ear is not tuned as well as the MoT equipment.
They are £100+ which I want to be sure it is money well spent.
1987/8 Autosleeper, 1.9dg (Automatic) hightop. Petrol/ LPG

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itchyfeet
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Re: Gunson Gas Analyzer

Post by itchyfeet »

personally I put the vehicle in on petrol.

If you want the LPG set up right in my opinion you need a lambda sensor fitted in the exhaust and an air fuel gauge so you can adjust it over time or a rolling road session.


I fail to see how it can be done well with a gas analyser and not moving because the engine is not under load.

a lean mixture with your foot hard down on a motorway could be damaging to the engine.

I have spend hours getting the mixture right with an air fuel gauge to find flat out on the motorway it's lean.
1988 DG WBX LPG Tin Top
1989 DJ digijet WBX Holdsworth Villa 3 Pop Top
itchylinks

kentishvanman
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Re: Gunson Gas Analyzer

Post by kentishvanman »

Hi,

[quote="itchyfeet"]personally I put the vehicle in on petrol.

As a matter interest.... why? I always put mine in on lpg 'cos that's what I use.
When I had my lpg conversion done (Gasure) the only tuning instructions I received were about the power valve ie the one on the rubber gas inlet pipe. About 3 year ago the MoT emissions reading for CO was 3.6% for some reason. The system was tuned, using a Gunson, by an Autogas engineer. His workshop was 80 miles away from me but his home only 20 miles. He agreed to the tune up at his home where he did not have his larger machine. Emissions are now .5% and HC 255 ppm vol.
I agree the engine is not under load but it passes the MoT and runs well so that wil do me. I do not have a rolling road centre within reach.
I am going to change my regulator, straight swap OMVL R90 but the tuning is the main issue hence the Gunson query.
'Sods law' that since receiving the new regulator my 'bus has taken on a new lease of life and is running probably better than it ever has.
1987/8 Autosleeper, 1.9dg (Automatic) hightop. Petrol/ LPG

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937carrera
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Re: Gunson Gas Analyzer

Post by 937carrera »

Have a look on ebay - if you have the space you can probably pick up a proper MOT analyser for less than you were going to pay for a Gunson.Gives HC and works at higher revs too.
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

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itchyfeet
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Re: Gunson Gas Analyzer

Post by itchyfeet »

937carrera wrote:Have a look on ebay - if you have the space you can probably pick up a proper MOT analyser for less than you were going to pay for a Gunson.Gives HC and works at higher revs too.


really? just did a search, I think you would need to have some experience in what to buy
1988 DG WBX LPG Tin Top
1989 DJ digijet WBX Holdsworth Villa 3 Pop Top
itchylinks

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itchyfeet
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Re: Gunson Gas Analyzer

Post by itchyfeet »

kentishvanman wrote:Hi,

itchyfeet wrote:personally I put the vehicle in on petrol.

As a matter interest.... why? I always put mine in on lpg 'cos that's what I use.
When I had my lpg conversion done (Gasure) the only tuning instructions I received were about the power valve ie the one on the rubber gas inlet pipe. About 3 year ago the MoT emissions reading for CO was 3.6% for some reason. The system was tuned, using a Gunson, by an Autogas engineer. His workshop was 80 miles away from me but his home only 20 miles. He agreed to the tune up at his home where he did not have his larger machine. Emissions are now .5% and HC 255 ppm vol.
I agree the engine is not under load but it passes the MoT and runs well so that wil do me. I do not have a rolling road centre within reach.
I am going to change my regulator, straight swap OMVL R90 but the tuning is the main issue hence the Gunson query.
'Sods law' that since receiving the new regulator my 'bus has taken on a new lease of life and is running probably better than it ever has.

because it;s easy to get a carb to pass much harder to get the lpg right and mine does not pass on lpg

they have to test it on the fuel it was present with.
1988 DG WBX LPG Tin Top
1989 DJ digijet WBX Holdsworth Villa 3 Pop Top
itchylinks

izzybarnard
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Re: Gunson Gas Analyzer

Post by izzybarnard »

To be fair I'd suggest that these types of gas analyser are simply for an indication and not an actual exhaust analysis.
If they achieved an uncertainty of +- 5% I'd be surprised. At this level they'd be unable to accurately set up a carb accurately.



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1987 Hightop with Subaru EJ25 Conversion

kentishvanman
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Re: Gunson Gas Analyzer

Post by kentishvanman »

Hi,

937carrera wrote:Have a look on ebay - if you have the space you can probably pick up a proper MOT analyser for less than you were going to pay for a Gunson.Gives HC and works at higher revs too.

I just did a quick search and they seem to be quite expensive. Do not really wish to go that far.
If I bought one of those neighbours might think I know what I am doing and was a proper mechanic. Mechanics are the last thing I will ever master and I struggle as it is. I only cope because of the 80/90 experts.
1987/8 Autosleeper, 1.9dg (Automatic) hightop. Petrol/ LPG

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937carrera
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Re: Gunson Gas Analyzer

Post by 937carrera »

https://www.ebay.co.uk/itm/Sun-Snap-On- ... SwAQBasVkC

Erith is your neck of the woods isn't it ?

£60 BIN, or Gunson s/h starting at £55 auction
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

kentishvanman
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Location: Weald, Kent

Re: Gunson Gas Analyzer

Post by kentishvanman »

[quote="937carrera"]https://www.ebay.co.uk/itm/Sun-Snap-On- ... SwAQBasVkC


Did not see that one. Tempted but it would take up limited space.
Thanks for looking and interest in my queries.
1987/8 Autosleeper, 1.9dg (Automatic) hightop. Petrol/ LPG

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937carrera
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Re: Gunson Gas Analyzer

Post by 937carrera »

No worries, might buy it myself then - I'm in Kent next weekend
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

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