Isuzu Repair: isuzu hombre 1997. clutch, blown head gasket, 1997 isuzu hombre

Question
QUESTION: i have a 1997 isuzu hombre there is a knocking type of sound at the bottom of engine and when i press the clutch it goes away. is this a release bearing and is there a way to grease it. the truck sat for 2 yrs.
thanx

ANSWER: Well does the knocking go away with certain speeds or is it constant?

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QUESTION: now that noise went away on its own. but another knocking noise is there and it is at bottom of engine, now it appears to go away when i accelerate it sat in drive for 2 years with blown head gasket had head machined doesn't blow any smoke. a buddy of mine had used washer fluid in the rad and leaked into cylinders. it is a 2.2 liter engine GM

Answer
Well it could be a number of things to be honest Robert. Like a thumping noise is usually a bad main bearing. Or a connecting rod bearing. Although a main bearing would knock as caused by sudden force of combustion which causes the piston and connecting rod to go down on the crankshaft bearing and crankshaft so I would consider this as well. These are very difficult though to diagnose accurately as I cannot hear it for myself so if you have any concerns or questions please let me know okay?