j_lambert_1

Ok so i just put my 5.0 back together after a quick tear down to find the cause of a knock. I checked the valve train, lifters and everything seemed fine. The knocking sounds like its coming from the drivers side valve cover and is pretty loud. Put all new gaskets and a timing chain on it cause the old one was really loose, put some cheap 10w 30 and fired it up. The knocking sounds louder than it did before, but i used to run mobil 1 15w 50 in it. Pretty sure its not and exhaust leaking cause it got new header gaskets too. If anyone could help or knows more about valve train that would be great, thanks in advanced.

Timspony

...might be coming from the lower end!?

j_lambert_1

idk definitely sounds like its in the head but not sure if i should just get new rockers and see if that fixes it, ive been wanting some better ones anyway lol

84conversion50

i would get a stethoscope and check out the pan. there cheap and it will def tell you where its coming from.

mjr46

I just finished puling a 351 out of a 94 bronco today that had a upper end noise, long story short Ifound the number 5 plug ,burnt electrode a had 70 psi compression, upon head removal the head had a crack between the exhaust and intake valve and the piston had so much piston rock side to side it wasn't even funny, long story short the rest of the motor is out now awaiting a jasper motor arrival, , did you inspect the oil/lifter galley plugs when timing cover was off to make sure none blew out, if one did oil pressure might be a little low, also you may have a bad lifter.

j_lambert_1

Had lifters out and stripped to long block everything looked brand new, nothing seemed to have any visual defects. This was my first motor tear down but like i said the knock was there before and coming from what sounds like the drivers side head. I will definately check out the bottom end tomorrow. I first noticed the knock developing when i was low on oil and it gradually got worst till the point that it is now. The motor has about 168,000 on the clock and i just didnt have the $$$ for a bottom end rebiuld.

mjr46

looks means nothing with regards to lifters since everything is internal and not visible with regards to what keeps lifter lash tight, since you ran it low on oil it may have a bearing issue now.

Portmaster

You should know that if you have a noise that just disassembly and reassembly isn't going to make the problem go away. A lifter can look perfect and still be bad.

j_lambert_1

obviously i dont know a whole lot about lifters and how to tell if there bad, apparently i shoulda got new ones while i was in there. What would i be damaging further if a lifter was bad also could my rocker arms be making as knocking noise for any reason.

mjr46

if a lifter isn't pumping up then the ticking would be the result of a rocker slapping around since the lifter isn't holding the lash tight