Valve job shouldn't cost 400 each, maybe on the high side 400 for both, might look for another shop.
I think you needs rings which means it needs to be bored, new pistons and the rest
Should do the heads when doing the block
That's bad for a rebuilt, weak for and old one
Check for moisture in 6
Could do a leak down test to determine if its rings or valves but my guess is a head isn't flat within .003
Do you have an alignment bar?
Best way to do alignment
Snug bolts in rear mounts.
Attach a lift on the thermostat housing and pick front of motor up barely off the front mounts
Adjust bottom nut so both nuts just touch the bottom of the mount.
Lower motor onto the mounts
Now adjust up or down...
The water system from the drive is not connected to the HW heater.
There can be a connection between the engine block and the HW heater to warm the water, but I'm talking about the fresh water which comes from the holding tank or shore connection
Post a pic so we can see
No
Post a pic of the rear mounts
Does the alignment bar go into the coupler at all, and if so how far?
If it doesn't go in, where does it touch (top, bottom, side)?
Can the fiber washer be moved?
Need to stick with this thread instead of starting another. Your new thread is in the FAQ section and no one can reply. Stick with this thread
Post a pic of your rear mounts
If the rear mounts were replaced with new style then you might not use the spring washers. If not then are the spring...