LPG Mot

Post Reply
Message
Author
mgrover
New member
Posts: 103
Joined: Thu Dec 19, 2019 8:41 am

LPG Mot

#1 Post by mgrover »

I noticed on my MOT test cert it said something to the effect of non catalytic test. Does that mean they don't actually test the Cat?

I ask this because I think these cats are on there last legs, and am fairly tempted to chop em off rather than replace them if they are not actually required since the car is LPGed. I know it would cause am error(I think), but am sure theres bypasses that could be used.

Brian_H
Intermediate Member
Posts: 2461
Joined: Mon Jan 23, 2012 12:21 pm
Location: Milton Keynes

Re: LPG Mot

#2 Post by Brian_H »

The standard for test on LPG is slightly different to on petrol, The MOT tester manual gives more details as it somewhat depends on the vehicle which exact test gets done.

https://www.gov.uk/guidance/mot-inspect ... on-8-2-1-2

That said, I've found some MOT testers really don't understand it and will either just test it on petrol regardless of what fuel its presented on, or test it incorrectly anyway.

Gilbertd
Advanced Member
Posts: 8823
Joined: Wed Apr 09, 2008 10:00 am
Location: Peterborough

Re: LPG Mot

#3 Post by Gilbertd »

If running on LPG when presented for test, it should be tested on LPG. Make sure you tell the tester that it is on LPG though in case he doesn't realise. You still may have a problem with some testers though as the rules say that if cats were fitted when new they should be when tested otherwise it is an automatic fail. Most take the view that as it is on LPG and cats are not required then it is OK to not have them but you may find the odd awkward one. The other way, rather than chopping them out, is to bash the guts out of them so it looks like they are still there but are only empty boxes (assuming they aren't on their last legs because they are rotting away).
96 Saab 900XS, AEB Leo, sold
93 Range Rover 4.2LSE, Lovato LovEco, sold
97 Range Rover 4.0SE, multipoint, sold
98 Ex-Police Range Rover 4.0, AEB Leo, daily motor
96 Range Rover 4.6HSE Ascot, AEB Leo, my spare


Proud member of the YCHJCYA2PDTHFH club.

mgrover
New member
Posts: 103
Joined: Thu Dec 19, 2019 8:41 am

Re: LPG Mot

#4 Post by mgrover »

Nah unfortunately the are solid as but toast af. I can hear the rattle when they get overly hot and they've started to ruin my top end by restricting exhaust gases

Also looking at that link does that mean the cats actually do something in this case and I need them?

LPGC
Installer
Posts: 4571
Joined: Wed Sep 29, 2010 6:01 pm
Location: Yorkshire
Contact:

Re: LPG Mot

#5 Post by LPGC »

To bash the guts out of some cats you need to cut them open, bash the guts out, then reweld where they were cut.

If the cat has a heat shield then to hide the cut/weld you'd do it where the heat shield will hide it... remove the heat shield to do the decore and refit the heat shield when done.
Full time LPG installer
Servicing / Diagnostics / Repairs to all systems / DIY conversion kits supplied with thorough tech support
Mid Yorkshire
2 miles A1, 8 miles M62,
http://www.Lpgc.co.uk
Twitter https://twitter.com/AutogasSimon
07816237240

Gilbertd
Advanced Member
Posts: 8823
Joined: Wed Apr 09, 2008 10:00 am
Location: Peterborough

Re: LPG Mot

#6 Post by Gilbertd »

mgrover wrote: Tue Jan 25, 2022 8:07 pm Also looking at that link does that mean the cats actually do something in this case and I need them?
Not if you present it for MoT running on LPG. If you take it in running on petrol, it will be tested on petrol, you will need them and it will almost certainly fail the emissions test.
96 Saab 900XS, AEB Leo, sold
93 Range Rover 4.2LSE, Lovato LovEco, sold
97 Range Rover 4.0SE, multipoint, sold
98 Ex-Police Range Rover 4.0, AEB Leo, daily motor
96 Range Rover 4.6HSE Ascot, AEB Leo, my spare


Proud member of the YCHJCYA2PDTHFH club.

mgrover
New member
Posts: 103
Joined: Thu Dec 19, 2019 8:41 am

Re: LPG Mot

#7 Post by mgrover »

Gilbertd wrote: Wed Jan 26, 2022 9:39 am
mgrover wrote: Tue Jan 25, 2022 8:07 pm Also looking at that link does that mean the cats actually do something in this case and I need them?
Not if you present it for MoT running on LPG. If you take it in running on petrol, it will be tested on petrol, you will need them and it will almost certainly fail the emissions test.
Perfect thanks

mgrover
New member
Posts: 103
Joined: Thu Dec 19, 2019 8:41 am

Re: LPG Mot

#8 Post by mgrover »

LPGC wrote: Tue Jan 25, 2022 9:38 pm To bash the guts out of some cats you need to cut them open, bash the guts out, then reweld where they were cut.

If the cat has a heat shield then to hide the cut/weld you'd do it where the heat shield will hide it... remove the heat shield to do the decore and refit the heat shield when done.
Am hoping to go for that, we'll see what the shop says on Sat.

Post Reply