I have an oil leak coming from the main seal in front and from the valve cover according to the dealer. They want to replace the timing belt/water pump/tensioner/belts and do a tune up as well. How hard is it for a do it yourself on the issue of repairing the main oil seal and valve cover gasket? ANYONE????
The Mitsubishi is a 1993 Montero SR 3.0L engine

Your lucky to only have this start at 203,000. Mine did it at 135,000. Got a local shop to do all of this for $600.00. Changed both cam seals as well, all were leaking.

It is probably not the valve cover, it is probable the cam seals at the back of the engine. All of those jobs are time consuming. To change the timing belt you have to take out the radiator and a bunch of other junk. The cam seals have very limited acces between the head and the firewall. I had the dealer replace those on my engine. I dont have a mechanic that I trust and felt the dealer would stand behind any future problems.