you stated you lost the spare keys. indicating you still have a set. visit the dealer. they can match up the factory ignition key, and will most likely have the cabin key as well.
There are about 15 Mercruiser keys. And about 10 cabin keys. My cabin used to have the same key as my tool box and the cabs on many construction equipment
Check with your dealer
Off the top of my head, no. Too many variations over the years. Would have to see the unit. However reach out to Ariens support line and they will get you the exploded view and section of manual
The WIX filters listed are some of the best. Much better than the private labeled filters in the Quicksilver box
Remember, Mercruiser does not make oil filters, they buy them and put them in their own boxes
The yoke thru the forward gear is retained by a hardened screw that is torqued and loctited in place.
Milky fluid indicates there is a preceding issue.
You have been pulling the drive ever 100 hours or yearly to inspect bellows, bearing and joints?
I have run RV antifreeze in a boiler with temps over 250.
I have run RV antifreeze in various RVs and cabine plumbing systems.
Never have had a color change
Did you drain the water from the system first?
That motor and drive are 50 years old
If the heat exchanger maintenance has been kept up, then it may last another 50.
However that chunk of iron is heavy
A 4.3/A1G2 combo can be dropped in saving 200# and adding 50-60hp
I bought GM key blanks and GM fobs from a GM parts site and used the local dealer to cut 2 keys and pair the fobs. Doing some legwork saved me a few hundred
