1990 TB42 gas issue

[4X4MUD]

Back firing may suggest timing issues. Are you sure the timing is set correctly?

Yeah I think so... Adjusted it via the distrubutor cap till it ran perfect... Got any ideas?

[threedogs]

Timing or air leak some where. Get your timing light out, GAS likes it a tad advanced.
Where is convertor mounted?? Maybe full of Air, Bleed air from gas side of things with Heater on HOT

[threedogs]

@ GSC That's what I'm thinking the convertor has an air lock in it and water not converting gas properly,
Not even sure if plumbed up right at this stage.

[4X4MUD]

Timing or air leak some where. Get your timing light out, GAS likes it a tad advanced.
Where is convertor mounted?? Maybe full of Air, Bleed air from gas side of things with Heater on HOT

I just did a heater hose 2 weeks ago and i flushed the whole cooling system. Its toped up with no air in cooling system. Gas converter is mounted next to the right hand side of the engine bay. Up against the fire wall between the over flow bottle and the fire wall.

[4X4MUD]

Dumb question - are you using water (check radiator and overflow) and water out of exhaust under power whilst stationary.

If the diaphragm in the converter goes it will mix with water from your cooling system depending on the model/setup. This will not only see you run your cooling system dry and cause potential havoc, but will see dramatic decline in LPG power and/or performance.

May not be, but identified the issue and fixed one last year for another member that had this very problem.


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Happy for you to check it out if your keen? Also, can i have your number please? Inbox it to me please

[taslucas]

Yeah I think so... Adjusted it via the distrubutor cap till it ran perfect... Got any ideas?

But it's backfiring. That's not running perfect?
Did you use a timing light and how many degrees advanced did you set it?
GSC may be onto something but id check for air leaks and make sure the timing is set right first.

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[4X4MUD]

Guys, Thanks so much for your help... I had it set perfect before it started back firing. I did it by hand and keeped driving it till it started to ping and then turned it a notch back and it was perfect. Im gonna do the plugs and leads and maybe the rotor button and then look into leaks and see what happends. i will call you soon scot

[GQ TANK]

One possibility re backfire and not running well.

This happened with the RB30 carby (TB42 carby is nearly identical)

The rb30 started running crap on gas not too bad on petrol (backfires poor idle etc)

The problem was due to the bottom part of the carby (Butterfly) assembly coming loose. I could grab the top of the carby and shake it.

To fixe, remove the 4 bolts that hold the carby to the inlet manifold
turn the carby over

remove the gaskets and space (don't damage as you may be able to reuse.

You will see three flat bladed brass screws (one had a hole though it.

Tighten the screws and reassemble and test vehicle.

[threedogs]

My take on most things gas, I've found 99% of problems
are electrical. Check under bonnet in the dark for sparks etc. and load it up [rev it]
If convertor not freezing you have water, when you topped up water was heater in the HOT position

[4X4MUD]

Yeah mate, Put the heater on and let the car run for 15 min with the idle on about 3000 till it got hot and the thermostat opened and then switched it off and checked the water level again after it cooled down and took about 1.5 litres and then checked it everyday for a few days in the morning to make sure it was full. I know 100% its not water because it backfires on high gear and low revers...