I recently bought a 93 dakota 4x4 with the 5.2l. First had to replace tires as they were garbage, then on first test drive had radiator blow the top off.

Put in new radiator and thermostat, worked ok for 20-30 miles then started overheating again. Eventually blew the upper radiator hose. Replaced upper and lower hoses and flushed the system. Now I got the cooling system working and it has a terrible knock coming from the valve cover.

I took valve cover off and can see the 8 rockers, starting from the back of the rocker arm, number 1 nad number 3 rockers are very loose on the lifter although the bolts are tight.

I have minimal mechanical knowledge and would appreciate any insight as to the probable fix needed to correct this situation.

 

To me sounds like your lifters have failed. They are hydrolic rollers. So they lost the fuild and collaspts. If you replace it right now before anymore damage happens I belive it should be a simple fix. You should replace all lifters. If you got the money replace the lifter rods and rockers.

 

I don't really understand your response? I took off the valve cover and then removed on set of rockers. I also pulled the lifter rods from under the rocker. They were certainly fouled and dirty, but were clear through the center.

If I were to try and guess at what my current situation is, I waould say either the springs under the two loose rockers are not springing back fully, or, there is an indent on the under side of the lifter rod (not sure what is there?) camshaft?

Prior to my overheating there was some lifter noise, but now it is extreme.

 

yah i've seen those indents on the rods but it's rare. i would say that when the engine overheated that the valve springs lost there tension. it's kinda like heating up a spring with a torch, it just don't work right after that. take the fact that two failed after it overheated and that kinda says it all.

 

Tore down the engine and found cracked heads. Sucks to be me. Replacing with another 318 out of cherokee. Hope it lasts.

 

That's rare to see a 5.2 go bad, how many miles did you have on that?

 

It had 162000 miles but I am sure that the overheating problems I experienced caused the cracked heads.