Re: Strange 327 Knock

Posted by Mike On 2011/7/5 14:35:04

Ok took it outside and got it good and warmed up, and did some stethoscope checking and found it's not related to the timing cover in anyway and it's not the fuel pump but is louder down in that area than the top.

After getting it totally up to operating temps and running it about 1000rpms where you here it the most at idle, i did the spark plugs one by one and found that when you remove the number 2 that a) it gets noticeably quieter and b)even if you have welding gloves on you can feel it shocking you if you pull the boots off.

Taking off numbers 1 and 3 made no difference, which makes me feel like it's not main related, and most likely a rod bearing?

Again, when putting it away, put it in park, gave it lots of gas to get over the drain bump in the driveway and pulled it in the garage and no noises. You really don't hear it under heavier loads, just at idle like i've described and when at cruising RPMS.

Wonder if that one bearing got some debris in it and the others haven't made their wear noticed yet? I wouldn't think the rod is bent or anything like that since it runs fine with no noise most of the time.
Can you drop the pan while the engine is in the car in a bathtub?

I'm wondering if i shouldn't just drop the pan and do new bearings and get away with it. If it doesn't work, that's $250 in bearings wasted but then again small price to pay to avoid having the engine out and professionally redone.

Comments anyone?