Hi to all...
Recently I buy a 87 Montero SWB with 4G54 engine with 167K miles. Actually I'm installing a new cylinder head due to corrosion on the old one. Looks like this engine never saw coolant just chlorinated water. Due to this, oil and water get mixed (milk shake). During the installation I notice that the camshaft and the cylinder head was damage on the journals. I know this could be caused by poor lubrication but I think I run the engine 1 or 2 times with the milk shake until I notice the problem. The questions are:

This attrition in the cam and head could be caused by the milk shake?

Or the oil pump could be failing?

Is time for a new oil pump?

Any comment will be appreciated.

 

if you want to do the pump you may aswell do the cam chain and guides.

Worn journals at 167k? Something not right...

 

without seeing the amount of damage, any bearing surface that is scored will have to be repaired/replaced - remember, a bad bearing surface will not heal itself

depending on how you consider "damaged" - I'd replace the head, probably the cam, the main & rod bearings, the oil pump.

sometimes, you can clean up the cam or crankshaft surfaces since they are much harder than the bearings.

Again, this depends on what you consider damaged.

luck,greg