just wondering if i should be worried about a very faint light deep knocking when the engine was running and i was laying under the car, it was very faint but obviously enough for me to notice it. its on 80k so isnt exactly old. ive had a main go on a 350 before but that was really loud 100 miles before it 'went' and i just wanted to get to my destination, unfortunatly the engine had other ideas. my main concern is my 2500 mile trip in june.........

 

Because you love ya car you'll worry. Look at the simple things first zs (anything loose in the engine bay etc). My car's only got to click or creek and I think something majors gonna fall off!
I think I'd only start to worry though if it got worse and more obvious over the next few weeks.

Speed.

 

cheers mate, not just me then, lol im guna pull the engine oct/nov time just need it in france before then ;-) cant beat these motors for cruising

 

Aren't they great? I love getting on the highway and cruising along at 55mph with the tcc locked. Smooth and steady.

When does the 'knock' occur? On warmup? At operating temp? There's a number of things that can make a 'knock'-like sound.

 

i believe it was at operating temp, saying that its running at 130 degrees at mo i have a thermostat on order to sort that. its very hard describing sounds, and may have sound worse as i was under the car, the chassis prob ampliefied - we all know the bearings go on these pretty easy, so any sound just makes me think bad thoughts. it was a very deep knock sound.
on another note i have access to an 86 blazer with the 2.8, i can have the motor out of that as my mates putting a tpi in it, would the 86 have the improved specs????? or would i have to check engine nos as it was the changeover year??

 

Probably something normal you're just not used to hearing. If you notice any change in performance pay attention to it. There won't be any difference between the '86 block in his blazer and your motor (aside from tbi vs mpfi). The blazer cam makes more torque, but hp suffers.

 

I know how you feel. I have a sound comming from my motor that sounds like a slight knock on startup and goes away after. I'm pretty sure it is just something loose but I always prepare for the worst scenario.

 

get either a tech stethoscope or use a long prybar/screwdriver and touch it to the area that the sound seems to be coming from, this will amplify what youre hearing. then once you normally think its gone, check it again w/ the same method and see if its still there. it could be nothing, or it could be the beginning of something. if youre that unsure, you might wanna get it professionally checked out before you take that drive in june my friend.

 

colapsed lifter will give a definate sound..

 

hey dave i like the big screwdriver prybar idea nice one, ive got a few days off now so ill have a play around with it. apart from slight tuning - no power below 2k, and a 'jerky' drive train - need to check trans mount. its running 'ok' and has most of its horses. pretty sure its not a lifter. or anything up top.