Rebuilt 2.5L making slight grinding sound during initial start.

[Barry Boyle]

Could swapping the bolt with the stud that supports the oil pick-up tube on a 2000 2.5L, have any adverse effects? After having done that and then some while installing a rebuilt engine; I noticed a slight grinding sound from the block @ the front end (with the serpentine belt removed). Engine seems to be running fine and the noise is barely discernable after 4 days. Just wonder if there's a cause for concern at the beginning of a 3-year warantee; otherwise plan on checking out the first oil change for metal shavings.

[4Banger5speed]

Did you rebuild the motor? If so did you use any kind of assembly lube? STP oil treatment is the best thing to use on close tolerence cam/crankshaft bearings and really anything that moves inside the motor. Just brush it on with a paint brush it is thick and tends to stick to stuff like that until you get her ready for initial fire up. Its not uncommon to hear a little squeel or slight grind in a newly built motor as long as it not a "knocking or pounding" sound and it goes away quickly. You say you have a warranty but a proffesionally built motor often in the fine print will not honer it unless it is installed by a certified mechanic/ garage. It is their "out" and they love to use it. Its a way for them to put blame on someone....ANYONE else. I would get a rare earth magnet (a strong small magnet available at most hobby and or science store) Put it on the oil pan drain plug. Leave it there until you make your first oil change. (which I would make between 300 and 500 miles) Carefully and slowly remove the magnet (on cold motor you let set overnight) and loosen the drain plug. Get it loose enough to turn with your fingers and slowly "snap" the magnet back on.... Back it out and see what you have. You could even get a few quarts of cheap Wal Mart brand oil and pour through the top of the motor and let it drain down and through the drain hole to wash out any metal shavings or dust that remains before filling it with the new oil that you intend on using. Just my oppinion take it with a grain of salt. As for your original question about the bolt you used.... Im sorry I have no idea. Good luck with your new motor!

[Barry Boyle]

Thanks for the response; the rebuilt engine was supplied by Advanced Auto for $1,800, and installed by a cetified Mechanic. After the first start we were postulating about what could be the cause of the sound and the bolt / oil pump pick-up tube stud was the only modification to the new block.

I now have 100 miles on the motor, and it still runs well and sounds better.