Those motor mounts, along with the port and SB side mounts, are basically molded rubber with a square metal base and stud that the bolts tie into. They shrink, dry out, and break/split all the time. It’s like your windshield wipers, the rubber vulcanizes and they they’re done. I’m more impressed that they last for decades in some cases. I wish my windshield wipers lasted more than 6 months. And the price to buy new ones is absolutely ridiculous.
To get at all three you have to take the swivel bracket off. It’s a relatively simple disassembly.
There are 4 screws at the bottom, two in the front, two on the port side. Hopefully the two port side screws aren’t stuck from salt water. They stick a lot up here in the northeast. You’ll need a long reach socket to remove them. There are two bolts, one on each side of the motor that you can wrench off. Don’t be surprised if the studs don’t twist off or break during removal. The last one is the front/bow side nut which you should be able to access via a ratchet and two extensions (or a long).
Once all are removed, you’ll have to use force to yank the thing off because they are wedged into the 3 studs (near the top of the motor). If it falls off, then you’ll know pretty quick which ones are no good.
If you have broken ones, go find a junk motor from 1957-2006 (18, 20, 25, 28, 30, 35hp of any of these years utilize the same ones), the motor mounts are all the same. Don’t pay more than $25 for a junker, and cannibalize the ones you need!
The front motor mount seems to change the most depending on age, weather exposure, etc. That one will literally shrink down by 25%, then it separates, or the bolts break, or whatever, but when you try to reinstall things or tighten down that nut,it will just split in half or break if it is already on it’s way out.
A shaky motor may not seem very evident until you pull that steering bracket off. But is sure makes a big difference in vibrations of course!
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