So, about a few weeks ago I did a seal job on my 88' GL. Took out the AC pump and made a bracket. I now run one belt for all pumps and pulleys. (is this ok?). Upon starting up and driving it after the seal job here was a loud clacking from what we thought was a lifter. After driving it 30 miles the clacking went away completely. After 270 miles, and as my fuel gage showed low the clacking started randomly again. I thought that maybe there was some crud getting captured in the hydrolic lifter passage and it had just worked out. I did a oil change the other day to get out any crud from the seal job th inking this would help. The clacking is still there and changes pitch (high pitch to lower) even when I maintain a certain RPM (oil pressure should be the same and not be the cause of pitch change right?) I have heard that running a oil detergent can help. what is the likely hood that it is some crud getting caught in there or lifter issue?

 

thanks for the help!

-Jesse

Without hearing it myself,I'm shooting in the dark, but my educated guess is that you might have a piece of RTV stuck in a lifter. If it is RTV, using ATF(basicly high detergent motor oil) or seafoam willn't do anything, because neither will breakup RTV.

 

It could be an obstruction thats starving a bearing, but the noise would be more consistent(usually). Try pulling the valve covers and check the valve train for slop at the back of the lobe(valve closed the most), if one is noticably sloppier than the rest, I'd get a new lifter. Lifters are more likely to give you inconsistent symptoms. Good luck

As said before, hard to diag without hearing it,,,

If the sound started right after you did the single belt conversion it is possible the belt is vibrating against something. You might want to remove the belt and run it for a minute or so to see if the noise is still there, don't run it long, before you pull the covers.

You can also use a long screwdriver between your ear and various parts of the engine to pinpoint where the sound is coming from. If it is a lifter you should hear it loudest from the valve cover.