cyamaha2007

iTrader: (3)

My sister is in school and she bought my old DD 2003 grand prix 3.1 pos. I have put 1 engine and 2 heads on this thing. It keeps pulling the rocker bolt threads out of the head ive tried helicoils like GM told me to. It was a 6 month fix each time thats it. I have a tig welder at my disposal. Can i get crafty?? This is a 3 grand car im not too worried about it. Hell if i could i would weld the steel stud to the aluminum head but that wont work. I want this thing out of my garage so any help will be greatly appreciated. Oh and so you dont ask all the rocker arm bolts are torqued to gm new spec. Also the push rods are the correct lengh.

livefast1

iTrader: (1)

you check preload? maybe bad lifters? something is wrong you can't deny that.

cyamaha2007

iTrader: (3)

The 1st engine was replaced by gm under warrenty for this problem. Im on the second set of heads on the second engine. All the gm techs i talk too say say that its a crappy casting. I needed space in the garage so i put the thing back together with one less rocker arm and one injector unpluged. A compression test revealed 2 cylinders low on compression. Time to remove the engine and find a donor. I wonder how long it will last. It seems to drive fine with a slight hesitation.

terryr

You can cross drill the stud and head and pin it like they did in the old days.

cyamaha2007

iTrader: (3)

thanks ill look into it.

Rich2279

iTrader: (7)

Ah, those 3.1L's are indeed a POS.

z28camaro1996

iTrader: (1)

put a ls1 in it problem solved

BigRich954RR

iTrader: (1)

try pinning it first

If you have to weld on the alum CLEAN CLEAN THEN CLEAN THE ALUM AGAIN to get all the oil out of the ALUM casting before you weld on it.

MikeGyver

iTrader: (5)

The weld and the metal around the weld will be as soft as butter. That is the nature of aluminum. Heat treating is the cure, but the valve seats will fall out in the oven, and the entire head will need to be re-machined.

cyamaha2007

iTrader: (3)

i gave up on the car it will run as a 5cylinder till she blows

98pontiac

3.1s are great. there intakes will eventually leak, usually every 100,000 miles... but other than that there great. along with the 3.4 and 3.8, both sharing the same intake problem.