new engine rebuild BACKFIRE IN INLET MANI???????

[Dubsingh 0]

Hi guys as you many know from my other posts i have rebuilt the engine on the g, turned her over and she started first time no problems, at this point i did not have all the sc pipe work hooked up and just let her ideal till she went thru a few cooling cycles.....i thought wicked alls well until the thermo stat packed in......taken it out for now as the engine is gonna be hot while running in even more so due to the tighter tolrances of the new parts. got it timmied up via the usual method, connected all the pipweork let the car warm up then disconnected the blue temp sensor and got it timed according to fly wheel mark (0) reconected the sensor and seemed ok till i decided to give it a few blips of the throttle.....low and behold on one of the blips i got back fire....it dnt do it all the time but presistant blips will induce back fire????wot have i not done right???

 

 

 

another problem is the water flage on the side of the head after running it seems the pressure seems to be escaping from here, causing the expansion tank to bubble up. i took it of cleaned it checked the seal which was ok, used instant gasket as extre precaution and now the water seems to seepin out of one of the bolt holes????....has any one got a pic of which way the flange goes on? asone side seems diff to the other. i am going to order a new one as i think the bras insetrs are to loose i pused them our wiv my hand is that normal?

 

dad reckons i should fix the water leak and just run the car in till everything beds in and then start to worry about fine tunning, he also sugested if the cars pinking on initial throtle its ok it will let the car rn a bit cooler....i knw that ok but how dose this effect the g60? never had one of these, did this on my valver it ran ok wiv out any problems

[flusted 0]

poppin in the inlet is lean mixture

[coolrado 0]

I had similar symptoms which where caused by a sticky closed throttle switch, it would idle fine but as soon as i gave it any throttle it would splutter and backfire into the inlet manifold, check the output from the closed throttle microswitch to make sure it changes when the throttle is opened.

[Dubsingh 0]

backfire sorted i nipped the mani bolts a bit more and checked for other leaks as it cnt be runnn lean all i smell is fuel lol. timing is spot on. but the car is being weird it seems to idle lumpy and sounds like its missing, soon as i throttle up it misses then smoothes out. when i let go of the throttle its fine for a few seconds then it goes back to missing....what have i done wrong or wot have i overlooked? plz help as i wana gether back on the road asap