Afstellen lpg

Forum voor Technische vragen over Amerikaanse auto's.
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Afstellen lpg

Post by yentederooij » Sun Jan 21, 2018 2:22 pm

Ik ben sinds gisteren eigenaar van een Lincoln Mark IV uit 1972. De auto loopt op LPG. De auto loopt goed alleen als ik voor een stoplicht sta dan begint de auto wat te pruttelen en valt soms uit. Ik zat zelf te denken aan afstellen.. Hebben jullie nog tips?

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Re: Afstellen lpg

Post by boyanka » Sun Jan 21, 2018 3:20 pm

Een beurtje?

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Re: Afstellen lpg

Post by yentederooij » Sun Jan 21, 2018 5:21 pm

Wordt volgende week gedaan, kan ook nooit kwaad natuurlijk

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Re: Afstellen lpg

Post by boyanka » Sun Jan 21, 2018 6:15 pm

Eerst maar eens het beurtje afwachten. Meestal zijn het toch de bougie kabels

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Re: Afstellen lpg

Post by FritsVrolijk » Sun Jan 21, 2018 7:17 pm

SjakBrak is van het forum verdwenen

Anders hem ff mailen dat is de LPG kenner hier

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Re: Afstellen lpg

Post by Camatruder » Mon Jan 22, 2018 5:21 pm

Mijne is een OMVL R90E en ik heb de procedure hieronder gevolgd. Loopt als een zonnetje.

I GOT THIS OFF A ENGLISH WEB SITE IT IS FOR OMVL 90E AND IT TOKE SOME FINDING TO,,,, LPG Vaporizers and Tuning - The very basics . . . .
« on: January 27, 2006, 14:27:28 PM »
OK - Here is a little guide to the very basics of a vapouriser and basic tuning.


Your timing and things are set reasonably OK. I'm not going to argue over whats the best timing as every engine is different. 6° to 8° BTC should be enough to get you firing.
You ignition circuit, sparks and leads are all in good order. No spark - No bark.

The Vapouriser

Based on an OMVL R90 vapouriser, and ignoring how it changes the liquid state LPG into gas, the part of the vapouriser that meters the amount of gas to the engine looks similar to this:

The big diaphram gets pulled ( downwards in the piccie ) by the suction from the manifold. This then pulls on the arm. In turn at the other end of the arm, the arm controls a little cap covering the main large outlet of the gas. The more the arm is pulled by the diaphram, the more the cap opens up the hole and the more gas you get.

How much the arm moves in relation to the vacuum is controlled by the spring. The larger of the 2 adjuster screws puts preload onto the spring that the arm has to push against. The more preload, the more vacuum required for a given amount of gas delivery.

The second smaller screw directly controls the opening of a smaller vent hole supply of gas to the engine. This supply is given regardless of the position of the arm / manifold vacuum. So even at idle with the throttle body all but closed over and no displacement on the arm ( and thus no opening of the main supply ), this vent will allow a steady flow of gas to the engine, and thus its called the idle bypass.

The smaller idle bypass adjustment screw is magnitudes more sensitive compared to the tension adjustment screw. Its in the range of 1:6. Supposedly 1 turn of the idle bypass screw will delivery the equivalent of 6 turns of the tension adjuster.

For both adjuster screws:

Turning the screws clockwise towards the the body of the vapouriser will reduce the gas supply. Turning them anti-clockwise will increase the gas supply.

Enough already - Just tell me how to adjust it all . . . .

[ If the engine doesn't run atall on LPG, then goto the bottom section to get some hints / ideas. ]

First of all, get the engine upto normal operating temperature.
Assuming the engine runs on gas, just not very well, then:

Open up the max power adjuster on the gas feed pipe that runs to the manifold. On the large rubber tube, there should be an adjuster valve which can close the diameter of the feed pipe. Turn this so that its fully open and is not restricting the flow of gas.

With the engine idling...
Turn the tension adjuster ( the large one ) outwards a lot to make the diaphram really slack. This will mean that plenty of gas is supplied to the engine when it sucks.
Then slowly turn the idle adjuster clockwise all the way in so it fully closes. If you find the engine is stalling, then unscrew the larger one to reduce the diaphram tension to keep it idling.

[If you cant do this without fully stalling the engine, then stop screwing the idle bypass inwards - leave it at a point where the engine just manages to run ]

Now with the idle bypass closed off, slowly start to the increase the tension on the diaphram by turning the 10mm adjuster clockwise and inwards.
Eventually, you should see the engine start to slow drastically down as the gas supply is cut off.
Stop when the engine is faltering under the normal idle speed, but still managing to run.
Now to get the engine back upto a normal idle, unscrew the smaller 8mm idle bypass adjuster . . . SLOWLY . . . this is a sensitive adjustment so do it a little at a time
On mine, after about 1 1/2 turns, the engine speed will pick up and start to return to a normal idle.
Adjust the idle screw until you reach a smooth idle speed. On mine its idles at about 800 - 900 rpm.

Now what you have set is the idle is controlled by this bypass adjustment, but if there is anymore demand from the engine ( by the throttle body being opened ) then the diaphram will immediately move and start to supply the additional gas.

Next step is to adjust that max-power adjuster that you fully opened at the start ( you did remember to do that didn't you? ) The max power adjuster just clamps and sets a limit to the top amount of gas flow that is given at the higher revs and loads.

To set this, get someone to rev the engine to about 3000rpm and keep it there. With the person holding the pedal steady, screw in the valve until you hear the engine start to slow slightly ( with the person still keeping the pedal still ).
Then unscrew ( open up ) the valve 1 complete turn.
Now you have set a limit that you know the engine will run at high revs with enough gas, but that you won't be letting an excessive amount through.

Then go back and re-do the 2 vapouriser screw adjustments just to be sure that the max-power adjustment hasn't upet the vapouriser setup.

And that should be enough to get you going reasonably well.

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Re: Afstellen lpg

Post by Jeroen_Sp » Wed Jan 24, 2018 9:40 pm

stel bij die lincoln ook de afstand tussen de pick up en de rotor af. Daar ging het bij mij altijd mis.
Wel even met messing voelermaatjes, niet met stalen.

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Re: Afstellen lpg

Post by gert » Fri Jan 26, 2018 10:17 pm

zou wel handig zijn om te vermelden om wat voor lpg installatie het hier gaat.....
er zijn nogal verschillen in afstelwijze.

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