XFChris

Both the mixer and converter had worn diapghrams,and needed fixing up, that's what I was told.

Wow I must have missed something. Car is going again, I threw in the towel and had it sent to a mechanics and minus quite a few $$$

My XF with a straight lpg 250 decided it didn't want to start one morning. It will crank fine, and kicked over and ran for a second when i sprayed starter fluid into the intake. So far, with the help of Panko, we've estabished that the car has spark, both the solenoids at the tank, plus the lockoff right next to the converter are getting power and clicking. The safety switch also seems to be working fine. I've disconnected the mixer from the throttlebody, smelt no gas coming out of there. Also took the soft large line from the convertor to the mixer off, only smelt a faint smell of gas. The mixer is a Impco 200, and convertor: a LG B2. I am suspecting that one of them has failed. Does anyone have other ideas of what has stopped my car from running?

Looks like I'll eventually have to chase a impco 425 setup. A 225 probably wouldn't have much gain over a 200, though I'd give it a go if i found one dirt cheap. I dare say it has a 2.77 diff in it now, does a crack above 70 in 1st, and sits at around 2200 at 100kmh in 3rd. I know the autos are a power robber of sorts, but with the info given in this thread, a mixer change could help greatly.

I have heard of, and seen Impco 300A mixers used on crossies, it looks like they are made for a dual fuel setup. with some sort of push/pull operated diaphram. I've heard of someone getting good gains with a impco 425, who ran the same cam as me, but I wonder if it will use much more gas while driving sedately? I may also turbo the car in future.

I bought a car early this year with a rebuilt EFI crossflow, running a Dynotec stage 2 cam (CM251) 214/214 @0.050 , 112 LSA, 2000-4800rpm. It's got a D head that has apparently been worked to suit LPG and the cam. The mixer is a Impco 200, convertor a LG B2 from memory. Since buying the car, I've put in a electronic dizzy that was recurved to suit the car, swapped out the stock exhaust for a 2.25" freeflowing system plus pacemakers. In the new year, ill hopefully get a 2nd lpg tank put in for extra range, convert the car from auto to manual, and do a proper CAI, using a shielded pod or a factory EFI airbox if I can make it fit. Then get the LPG system tuned. Can anyone who is well clued up about LPG tell me if the Impco 200 mixer is up to the task of running my car well, or should I be looking at something else to get better efficiency? As it is now, it drives well under part load, but seems a bit underwhelming at WOT.

Can anyone running these up front comment on how comfortable they are, when set on a softer setting? Just wondering how good they'd be for comfortable driving in a daily.

Thanks Valvebouncer. I gravity bled the brakes yesterday, and the brakes feel significantly better now, it's made the car driveable again.

I just done the above tests , and the master cylinder checks out ok. So that weeping caliper must have let in air over time :S

It has the factory booster that is integrated into the master cylinder I believe. I'd have thought if it lost vaccuum to the booster, the pedal would be very firm, but I will have a look at the rubber line during the week if I have time.

Yesterday the brakes in my XF (disc on all 4 wheels) didn't work as well as they used to, the brake pedal was super spongy, and it took a lot of pedal travel to get the car to pull up. Previously the car would stop quite well. I have given the car a quick look over, brake fluid in the reservoir was just about at the full mark, and there was no leaks I saw, aside from a weep at the back of the rear left caliper, where the handbrake plate bolts into the caliper body. Aside from that weep possibly letting air into the lines, what else should I be looking at, as the cause of the poor braking?

^This If its a common brand of tank, there will be a service panel cover, which will be secured by 2 nuts or similar, take that off, You then should be able to see, amongst other things, a brass? looking knob, or tap. Turn that fully clockwise and that should cutoff gas supply from the tank. Tanks do not need to be decanted to change a converter, just cut off the gas supply as described above.

You thinking of making it a work truck? Could be a good way to earn a bit of coin, while getting to drive around a massive V8 truck

If you can find a XF that runs EST at a wreckers, take the black plug on the side of the dizzy, and take the plug and some loom. Wire the MSD wires to the offcuts of the loom. I have the pinouts written somewhere if you go down that road. I would say so. Only MSD small black and orange are to be connected to the coil. Connect the factory tach wire to MSD grey wirre.

You could bypass the TFI module - remove it. And wire the MSD direct to the dizzy. I got mine working like that. Though I'm not sure how reliable that method is long term. I'll have to look up what wire goes where.