coco95z28

95 z 128k miles

i replaced the water pump about 5k miles ago

car has orig. opti spark plugs and wires were changed 40k miles ago by the previous owner's friend of a friend (who knows if he changed all of them)

just did an oil change and have NO metal floating in the oil not even shavings

problem #1....................
car has a bad miss, every gear after 4600 rpm car acts like its hitting the rev limmiter

problem #2..................
im getting an annoying (knock, kind of noise- like a bearing or something) its external like its on the outside of motor... in the front.

we used a mechanic's stethoscope and a 3 foot wood pole to press up against the oil pan, top of motor, both valve covers,

its real, real, real, loud and bad right around the water pump

my question is... what does the water pump attach too called? does it attach right to the cam? are there bearings that can go bad in the pump? if i get an electric pump can i delete that shaft (if it is possible)

my next question is as far as the opti goes, is there any type of gear in them? that mybe goes bad? maybe thats causing the miss and also that noise?

thank you for taking the time to read all this, just want to get a good idea how this stuff works before i get into all this....

coco95z28

ok did some work on the car, i took the water pump off and it seems fine, spins free, no viberatins.

i used a pair of pliers and started wiggling that shaft that comes out of the motor (for the water pump) and it doesnt go in or out, it just wiggles around a little bit like its loose. seal still looks good though.

so is that shaft even suppose to wiggle like that?

and if not, i can pull the opti off, and crank hub off, since the water pumps off, how hard is it to remove that (timing chain cover?) i dont know whats back there?



also how far does the front of the oil pan have to come down? and what is the correct way to do this???

and if i just remove it all together (since its going to be off) i have a welder for the hole, i may just put an electric water pump on to delete that shaft?

JAKEJR

When did all this begin? Recently, all at once, gradually getting worse over time? Did it begin after you did some work on the engine?

Jake

My son, Ryan M. Cameron, graduated from West Point on 22 May 2010! He was commissioned as a 2nd Lieutenant and I pinned on his first pair of "Butter Bars" PROUDEST DAY OF MY LIFE!!

coco95z28

no no work done, i swear it just started over night. (i did beat on the car a little the night before) is that shaft suppose to move a little? i mean thats sure where that knocking, bad bearing noise is comming from...

4K+Converter

How old is the wire that goes from your coil to your opti? If its real old it could have gotten brittle and broken a bit inside the wire while you were working on the car. I had a similar problem, the car was missing hard after 5K after doing heads and cam. I replaced the coil to opti wire and it started missing after 6K. It turns out the Autozone coil I had on there wasn't up for operation over 6K, so I swapped in a MSD coil and it revved nicely to 6600.

madmike9396

iTrader: (29)

im going to say opti not sure tho but that would be my guess

97 SS LT1

problem #1....................
car has a bad miss, every gear after 4600 rpm car acts like its hitting the rev limmiter

Have you figured this out yet? i have the same problem after my cam and head swap!

defaultexistence

iTrader: (11)

yes the water pumps splined drive gear will wiggle a bit ,yes it can be removed once you have the timing cover off,no you dont have to remove it to install an electric water pump(EWP) "i didn't", the miss is likely the opti, especially if the ex-water pump ****'d on it any as it went out. the oil pan and timing cover mate into into an approximate 1/4in grove on the timing cover......ehhh