Texas Deep Freeze = Cracked...something on 2016 Mercury 4.5L Alpha

Speaking of which, i was in the store buying bottom paint today, and on the wall they had a list of reman long blocks and prices. No 7.4. Had 8.1. is 8.1 a bored out 7.4?
 
Nope. The 8.1 is GM's metric motor. The 7.4 can be bored and stroked to increase its size but usually call it a 496.
 
Many "Boatmen" are moving away from I/Os in favor of the new 4-stroke Outboards. Certainly, the boat manufacturers are moving in that direction with many new models as well.

This thread certainly demonstrates why that may be a better approach.

Regardless of freezing issues, the 3 hour winterizing procedure that is now a 20 minute task is enough for me to make the switch.
 
Well Jim I agree about OBs being easier to winterize. But (always a but), was at boat store today, merc 175 was 16k. Takes 2 at 32k to make the same power as 1 7.4 for 7-8k. So for me - No.
 
Pirate Lady said:
Well Jim I agree about OBs being easier to winterize. But (always a but), was at boat store today, merc 175 was 16k. Takes 2 at 32k to make the same power as 1 7.4 for 7-8k. So for me - No.
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Obviously, not practical if you are re powering, but for a new build IMHO its the only way to go.
 
That said, I love my outboard on my zodiac, been on a lift at marina all winter, self draining, but (there that word again) I can replace cheap if anything happens to it. I got a prob hanging 32k off transom that 7k does same job.
 
If you buy a 190, the OB to I/O price is the same, comparing equal performance.

If you go with a 320 Dancer, the OB is a (roughly) $50K premium. But it also is comparing 600 HP vs. 750 HP for OB.

The 400 would provide a $100K price increase, also comparing 760 HP vs. 900 HP for triple OBs.

I guess its all a matter of personal preference.
 
Marcus:
I wish you the best of luck on this. The freeze plug did relieve some pressure. There is no reason to anticipate the worst.
Early on, didn't you say you used a commercial winterization kit of some sort to add polypropylene anti-freeze. If that's right, were there instructions?
There are bound to be some disappointments in boating. The risk tends to define the participants.
 
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Arminius said:
Marcus:

Early on, didn't you say you used a commercial winterization kit of some sort to add polypropylene anti-freeze. If that's right, were there instructions?
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I've used these kits for many years. I don't know which one the OP used, but mine did indeed come with instructions.

All the expert gurus warn against using these kits because its so easy to not have them work right. The key is that the thermostat has to open fully, thus the engine has to be fully warmed up.

The newer engines with all the plastic blue plugs are much easier to drain with assurance that all the water is out. In my case all I had were 3 brass plugs and they were a PITA to take out and get sealed back up. I replaced them with brass stopcocks that didn't need to be resealed. Every time I did the task I would drain out a small cupful of coolant and check the SpG. I always found that what came out of the block, the manifold and riser were almost straight antifreeze. But, as they say YMMV...
 
Marcus said:

"As far as winterizing, the procedure I followed was to run the engine in the water until it was at normal operating temps, then on my lift (engine off) I drained it completely through the seawater drain. Then, I attached earmuffs connected to a CAMCO winterizing kit and let the engine pull the propelyne glycol through until it began expelling through the prop. Shut off, done."
 
Damage confirmed. Despite my efforts I'm guessing the thermostat wasn't open long enough to let the antifreeze circulate. :(
 

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JimG said:
Marcus said:

"As far as winterizing, the procedure I followed was to run the engine in the water until it was at normal operating temps, then on my lift (engine off) I drained it completely through the seawater drain. Then, I attached earmuffs connected to a CAMCO winterizing kit and let the engine pull the propelyne glycol through until it began expelling through the prop. Shut off, done."
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If it was indeed drained first there should have been no water left to freeze. Adding the AF should have done no harm (you would think).

The "kit" calls for running a full 5 gallons thru the engine, not just until pink shows up at the exhaust.
 
Sorry to hear that Marcus. Please keep us up to date on the re-power if you choose.
 
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