Replacing camshaft bearings in 4.0 Inline 6

Is buying a $150 camshaft bearing tool the only reliable way to replace the camshaft bearings? Can these be rented at local autoparts stores?

They very well may be available for rent at a McParts store but you might consider that proper installation is difficult for the beginner with the engine on a stand and neer impossible with the engine installed.

Yes and maybe…Call a parts store and ask…

A better way is to have a machine-shop do it…And replace that welsh plug at the rear of the cam bore…The oil holes in the bearings must be lined up EXACTLY or it’s certain disaster…

The way I was looking at these camshaft bearings was like a clock. The bearing hole had to be at X…say 2 o clock for arguments sake. How much lee way is there on that? I’ve read in a couple places that you have between 2-3 o clock vs being exact. Does anyone have any experience with this? Saw an idea to bend a coat hanger to confirm the bearing hole lines up with the hole in the block.

Also, the haynes manual suggests using plastigauge to check bearing clearance between the bearing and the shafts (crankshaft now not camshaft). Is this the best way to do this?

Yes, use a Plastigage on the rods and mains…The cam bearings need to be lined up pretty close…In some engines the oil going up to the rockers originates from a passage in the cam bearing gallery. If the holes in the bearing shells don’t line up, no oil flows to the rockers. This is not true of all engines, but it is a common arrangement…