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Reducing CO EMISSIONS after MOT FAILURE
Posted: 10 Sep 2018, 17:04
by maxstu
1985 2.1 on Pierburg and CAMPERSHACK BLOS LPG.
LPG decommisioned for now. MOT failure due to excessive emissions of 5.82. Max allowance is 4.50 percent. Not really far off but mixture screw set at about 2.5 from fully in.
However, how can the carb breathing properly with this BLOS thingy blocking intake between filter (K&N Style) and carb pancake?

Obviously l can remove it. But when l get LPG operating again how does this work? Is it moved by vacuum ?
Regards
Stuart
Re: Reducing CO EMISSIONS after MOT FAILURE
Posted: 10 Sep 2018, 21:09
by 300CE
Stu, would they allow you to use the gas analyser at the mot station so you can adjust the carb to reduce the emissions?
Re: Reducing CO EMISSIONS after MOT FAILURE
Posted: 10 Sep 2018, 21:37
by maxstu
300CE wrote:Stu, would they allow you to use the gas analyser at the mot station so you can adjust the carb to reduce the emissions?
Hi Justin,
Hope you are well?
They might well do. However the question lm asking is how one sets correct mixture with the BLOS slide blocking 4/5th of the air intake betwix air filter and carb?
Its not moving when l gun engine on petrol as LPG is disconnected. And it should move back allowing open airway at mid full throttle.
Is it vacuum operated or electrical?
Re: Reducing CO EMISSIONS after MOT FAILURE
Posted: 10 Sep 2018, 22:52
by mrhutch
i'm guessing you didn't present running on gas because its not working?
whats the problem with the LPG system? fix that first.
Re: Reducing CO EMISSIONS after MOT FAILURE
Posted: 11 Sep 2018, 06:09
by maxstu
Just found this on TINLEY TECH WEB
Product Description
This BRC Blos LPG mixer has a 70mm inlet and outlet. It is designed to fit in the air intake hose and works in a manner similar to a Stromberg or SU carburettor, in that it has a diaphragm that lifts a slide as the air flow increases. The lift allows more air into the engine and proportionately more LPG.
This version is fitted with a vacuum-operated slide lifter that allows freer air flow when running on petrol. This can be an advantage on engines that are sensitive to inlet restrictions.
A single model of BLOS fits the full range
of vehicles. The stainless steel gas feeding pipe is currently supplied with four types of slits:
Slit E: normal flow (80% of the vehicles)
Slit D: increased flow (15%of the vehicles)
Slit A: much increased flow (5% of the vehicles)
Slit P: weak flow
This mixer is fitted with a D slit.
Re: Reducing CO EMISSIONS after MOT FAILURE
Posted: 11 Sep 2018, 06:12
by maxstu
mrhutch wrote:i'm guessing you didn't present running on gas because its not working?
whats the problem with the LPG system? fix that first.
The BLOS LPG vacuum slide sittimg between air filter and carb is not fully opening on petrol too allow full air flow.
will remove BLOS temporarily for emissions testing
Re: Reducing CO EMISSIONS after MOT FAILURE
Posted: 11 Sep 2018, 06:33
by ajsimmo
maxstu wrote:
The BLOS LPG vacuum slide sittimg between air filter and carb is not fully opening on petrol too allow full air flow.
They don't.
It'll move far enough to let the air demanded through. It's not vacuum operated on petrol either, I've never fitted that model. You're reading the wrong blurb.
Why not present it on gas? To service the blos just find the initial setting, then remove the centre tube, clean it (and the hole in slider plate), polish if scored, lightly oil and replace. Check plate now rises and falls smoothly by hand. Refit. Adjust on gas analyser.
Am I correct in that you've swapped the engine for a 2.1?
Sent from my ONEPLUS A3003 using Tapatalk
Re: Reducing CO EMISSIONS after MOT FAILURE
Posted: 11 Sep 2018, 07:04
by Sir Brixalot
As far as I know unless the law has changed recently, vehicles on LPG don't have to be emissions tested. My blos rattles internally, any idea what would cause that Andrew
Re: Reducing CO EMISSIONS after MOT FAILURE
Posted: 11 Sep 2018, 07:43
by ajsimmo
Sometimes they chatter at idle, as the plate barely opens at that and the inlet pulses causing it to bounce on the bottom. Can be improved by screwing in the emergency plate opener screw a turn so it holds it open a fraction at idle.
Btw Stu, if you want to take assumed inlet restriction out of the equation for MOT on petrol just screw this screw right in. You'll find it makes little or no difference, but at least then you will know that. Then adjust your carb.
Sent from my ONEPLUS A3003 using Tapatalk
Re: Reducing CO EMISSIONS after MOT FAILURE
Posted: 11 Sep 2018, 09:17
by maxstu
ajsimmo wrote:
Btw Stu, if you want to take assumed inlet restriction out of the equation for MOT on petrol just screw this screw right in. You'll find it makes little or no difference, but at least then you will know that. Then adjust your carb.
Sent from my ONEPLUS A3003 using Tapatalk
Early coolant 1.9 to 2.1 on rebuilt Pierburg 2E3
Thats the bit lm after. Cheers Andrew.
Van came to me as non runner due to carb meltdown. A mess in inlet manifold heater plate and melted pancake had bog seat. LPG System without cut off solenoid for petrol. I guess l could flip to lpg and blank off fuel supply?
Donor 2.1 fitted with 1.9 inlet manifold and rebuilt carb. Runs really well. Idles and choke operation spot on. Nearly that is

Apart from a slightly high Co emissions. 5.82
Next on list to either purchase solenoid from you or Tinley Tech?
Regards
Stuart
Re: Reducing CO EMISSIONS after MOT FAILURE
Posted: 11 Sep 2018, 09:22
by maxstu
Sir Brixalot wrote:As far as I know unless the law has changed recently, vehicles on LPG don't have to be emissions tested. My blos rattles internally, any idea what would cause that Andrew
Only if from manufactory they had LPG, and or no alternative fuel supply perhaps ?
Re: Reducing CO EMISSIONS after MOT FAILURE
Posted: 11 Sep 2018, 09:38
by 300CE
maxstu wrote:300CE wrote:Stu, would they allow you to use the gas analyser at the mot station so you can adjust the carb to reduce the emissions?
Hi Justin,
Hope you are well?
They might well do. However the question lm asking is how one sets correct mixture with the BLOS slide blocking 4/5th of the air intake betwix air filter and carb?
Its not moving when l gun engine on petrol as LPG is disconnected. And it should move back allowing open airway at mid full throttle.
Is it vacuum operated or electrical?
All good cheers mate - my bus is up for it’s MOT on Friday so will see how that goes!
Sorry mate, wouldn’t have been able to provide much assistance with your predicament but looks like you’ve got it sorted

Re: Reducing CO EMISSIONS after MOT FAILURE
Posted: 13 Sep 2018, 08:26
by maxstu
Well lm finally waving a pass certificate.
Took a bit of adjusting and fettling. But garage is very VW (Kings, West Malling) friendly and got the CO readings down to around 3.6.
Sorted headlamp issue. Connector incorrectly wired

£9 wasted on new bulbs.
Rear brakes adjusted and handbrake set.
Rest day today...well chain sawing wood. Its my de-stress therapy.

Re: Reducing CO EMISSIONS after MOT FAILURE
Posted: 13 Sep 2018, 09:21
by maxstu
FOILED ONCE AGAIN!!! Small 52mm joining pipe leaking nice new coolant.
So one newly MOTed & insured van out of action due to a £5 piece of poxy pipe. And my keeper van uninsured for now.
Wheres me chain saw?

Re: Reducing CO EMISSIONS after MOT FAILURE
Posted: 13 Sep 2018, 09:49
by 937carrera
You'll never get a chain saw in there, you'll have to use a screwdriver
Poxy pipe to be delivered tomorrow ?