Quote Originally Posted by Throbbinhood View Post
For what it's worth, mine runs like a pig too in this weather. I've wound off my electric choke, and am missing the heater grid and heater flap stuff, so I'm not surprised - it's not my daily so it doesn't stress me too much.

What I have noticed though, is that I think my carb ices if I haven't let it warm for long enough. Generally happens if she hasn't warmed much, and I jump on the freeway on these cold cold mornings. After a while at 100kph, she just starts losing power.

It still idles fine though at that point, so it feels like the secondary is closing or something like that. If I pull over for five minutes and just let it idle, I can take off again with it having warmed up, and the issue doesn't re-occur.

If I sit in traffic first, or let it warm up for longer at home (or just go on a more start stop drive first), I don't have the issue. #carbylife
Yours is slightly less complicated to pin point the issue 'cos it's pety only as oppose to mine.

You symptoms above(losing power after well warmed up) can be either due to intake sucking in the too moist air or it can be the mixture leaning due to faulty fuel return valve. But, afaict, RB30 fuel return valve is pretty good. It's controlled by an engine revolution sensor unit under the dash(kicks in when the rpm get to 1500-2000).

In mine, heater grid and flap are all in good nick as intended in the stock setup. Only thing's missing is the directional cup under the carby(inside the intake manifold) & the aircleaner preheat plumbing duct from the exhaust manifold shroud. I can't do much about the carby/manifold directional cup 'cos it was shattered into pieces late 2015 for some weird reason. I can put back the aircleaner preheat duct back(I would need an aluminium duct to join it to the air cleaner duct/pipe), but I don't think it can make much of a difference. We hardly get any really cold weather in Melbourne. Those preheat duct setups are mainly for sub zero freezing temperatures, which we usually don't get here. I think the carby is an absolute bastard to start with. I might have to bite the bullet and get a new carby. It's that I can't justify that much money for a carby, when I can put that money and add another couple of hundred bucks to get a good EFI engine. I'm also suspecting the LPG converter for LPG running like crap. I think the converter either need a rebuild kit through it or a new replacement. Mixer looks good, but I've heard that looks probably not the best way to judge the wear and tear of the mixer. Problem for me is that my Impco 300A mixer looks spotless and no rips or tears in the diaphragms.
I've seen raggedy looking mixers of the same model number running like a purring cat.

It's better to diagnose it rather than throwing a grand worth parts at it, to find out the problem's still there. And I like diagnosing it myself. That's the other problem.