[ZHFairlaneV8]

ive having a real problem with my Carby on the ZH. First when the car is cold (like in the mornings) the car will stall if i dont continuously rev the motor, also it seems to flood (as you can smell petrol), and its REALLY hard to start, ive checked the auto choke and its got power and it actually appears to work so what could it be?

 

[ZH_302]

Are you sure the auto choke works as thats what it appears to be
Accelerator pump is probably stuffed aswell, Do you have to pump the pedal a lot before starting?

I wouldnt stuff around , just get it rebuilt. Should cost you around $300 exchange
Just make sure they include the auto choke and secondaries diaphrams in the price

 

[ZH_302]

Forgot to add that you could just ditch the Carter and put on a Holley, a lot of people will tell you to do this because the Thermoquad's are hard to setup properly.

Once setup they are a good carby though

I prefer to keep my cars original, so I chose to rebuild the Carter

 

[ZHFairlaneV8]

Thats exactly what i have to do, pump the accelerator quite a bit to start it, and floods, i was thinking of replacing it with a Holly 650 or ive been told by a mechanic that a Eddelbrock carby would work well on it. With the Holly would it use More petrol? because at this point in time i get about 100k's and gone thru about 2/3'rds of a tank. Is this too much???

 

[GreenMachine]

80L tank (or, even worse... possibly the 100L option)

2/3's of 80L = let's say 54 litres

54L/100k's... not great economy! My ZH 302 is running like a pig, similar carbie problems to you, i'm getting between 260 (city/thrashing) and 400 (highway) k's per tank...

Just remember - chances are the fuel guage is NOT accurate... I ran mine dry three times before i worked that out. And once they're dry, they're a bitch to prime and get running, not to mention the rubbish that must've gone in to the carb!

 

[ZHFairlaneV8]

Yea The Gauge is very screwy, if i thump it :AAHHH: the gauge will go like 3mm towards Full, Also This morning i drove from my mates house to mine and back and the gauge went from 3/4's of a tank to 1/2!!!!! :AAHHH: which is like 50k's. Then went from mates place to shopping centre which is like 10mins away and it now says 1/4 left!!! its a Stock ZH (302,C10) So im guessing this carby is the problem here! Ive cleaned the entire carby with carby cleaner, and in the throats aswell, there appears to be No fuel leaking or air leaks. Hmm....

 

[ZHFairlaneV8]

Oh yea and its the 77ltr Tank (80ltr)

 

[GreenMachine]

well, if everyone can just put up with their crap Thermoquads (and let's face it, there's LOTS of us!) for a few weeks, i'm going to rip mine off, pull it apart and see what the go is. I'll do up a tutorial thing when I'm finished.

Just got to get the exhaust fitted on monday... mmm... twin system...mmmmm

 

[ZHFairlaneV8]

Exhaust sounds nice....

 

[GreenMachine]

yeah... twin 2.5's, Genie extractors, both pipes going up the driver's side and exiting together in the cutout... should be sikmate! will look ultra tuff from the back with the 245 tyres!

 

[XEesp351]

Hi, if possible id recommend to keep the Carter, i love em for a street driven car, Holley maybe better for racing. Saves hassles at rego, and with coppers. Ive tried a 600 ,725 and 750vac Holleys, but have gone back to good old TQ. I may try a 650 DP as i have a 4 speed?
Heres a few links to get u going,
http://anusf.anu.edu.au/~jgs900/thermoquad.html -best place to start.
http://www.invisionphoto.com/projects/CrtRbld.htm
http://thermoquads.com/index.html
just do a search in copernic for them, heaps of info.
btw, our TQ's r rated at 625cfm, but in USA they r rated at 850cfm, they r exactly the same specs, apparently they use a different way of determining airflow than Holley. They also make a 1000cfm, but we never got it.
good luck.

 

[Chris Brooks]

You said that the auto choke has power. What voltage is it getting? It is supposed to be getting 7 Volts from the back of the alternator, not 12V from the battery.

Mind you, that would be making it run too lean soon after starting as the choke would heat up too fast. Just something to check.

Thermoquads are a good carby for the street when they are running right. It's just hard to get bits and even harder to find a mechanic that knows anything about them. They will mostly tell you to dump it and get a Holley. Your choice but if you can get it sorted out it will keep ya happy unless you have a big cam. Thermoquads don't like poor vacuum signal.

Good luck.