gq tb42 woes

[Fuddled]

hey guys at the end of my patience with this car, i got cheap then took out and backfiring so i fitted pertonix 2,extended rotor button and put a carby kit through it was running fine on both fuels then lost power on acceleration and if i pushed it would backfire through carby now at home in shed its not running on lpg runs on petrol but if i go to quick to flattern accelerator it backfires through carby little worrying lol i pulled carby apart again cleaned with carb cleaner and blew out all jets etc no difference any ideas before i burn the bloody thing

[Silver]

backfire through carbie while running on petrol = running lean on petrol? Check fuel filters including checking for one that a previous owner has put somewhere sneaky? Look for vacuum leaks?

Double check ignition timing?

[growler2058]

Gday mate welcome aboard gotta friendly mob here fulla great info and advice. Jump over to the intros and say gday mate youll get a better response ;-) great to see another crow eater on board

[Morton]

having some of the same issues, reset ur timing, check the coil, if spark is good go through the leads one at a time & test for spark & spark consistency, throw a scewdriver in the end of the lead & place it near metal, it should arc across, after that go through ur plugs one at a time, place the plug in the lead & leave it near metal, look for the same consistency in spark, check number one plug in particular, if you are getting a strong spark from the coil but a consistant weak spark from your leads then replace the leads first, if it is the same then it is related back to ur dizzy ie: cracked cap, condensor/resister thing etc, screw ur fuel mixture screw in all the way & back it out 1.5-2 turns then the idle screw in or out till it is at 7-800 RPM, another thing to look at is the gasket seal for the inlet manifold, this will cause those problems, sometimes u can here it sucking air, this is were I am at with mine at the moment

[Fuddled]

today i measered voltage at ballast resistor 13.4 on input side 12.8 on side to coil same voltage at coil also put my test light on neg battery terminal and had power both sides of coil is that normal

[bazzad]

Hi Fuddled,
Check your timing to make sure it is ok and in spec, then have a look at your valve clearances, Need to be sure that they are closing correctly. Make sure that when you are at TDC you can move the rockers a little bit.
cheers
bazza

[Morton]

today i measered voltage at ballast resistor 13.4 on input side 12.8 on side to coil same voltage at coil also put my test light on neg battery terminal and had power both sides of coil is that normal

Mate cant tell you, I leave that for the boys, I just bang my head till someone comes over & does some of the tests like you are talking about, they understand it all a bit better, I just do all the grunt stuff which usually gets me out of trouble

[Fuddled]

Hey guys I replaced everything found out was out of gas gauge on dash full and tank gauge empty at least everything's changed thanks for help guys