This is the troubleshooting flow chart for both TB iV & V

https://bpi.ebasicpower.com/faq/MERCSB92-11.htm

Take this for what its worth as I haven't done a SBC stroker. Most of my engine rebuild epxerince is on 65 GTO's ...and I would just stay with of the shelf full dish pistons to keep it simple...
...

If you look at other similar posts Rick had a habit of arguing with everyone , especially this long tirade on piston profile we have all seen a hundred times...Jim who runs this site and marine...

Drain the raw water between uses. Should be in the mercruiser docs that come with the boat or look online

Does it have closed cooling ?

yes the oil does get pushed out to the cylinders and back.what I did for the same reason you are looking to change it, was suck the reservoir dry with a turkey baster, refill, run the drive up and...

and the correct information is the OP can swap his engine to a 4.3 and go up in pitch on his existing drive and this will work very well for him. Any of the other horse $hit you have written like the...

rick why don’t you contact mercruiser since you seem to have sooooooo much time on your hands

stop obfuscating the OPs original question with long winded off topic posts. We are not talking about...

this is just plain wrong , the experience I lay out in post #3 is evidence of that. I’ve used this boat for 5 seasons and works perfectly in all phases of operation - holeshot, cruise, WOT.

im...

best post in this thread. Started with what is a workable compression ratio? ..... and end up with all this crap. I’m just glad we didn’t get the model T ignition system drawings again.

it’s not...

I suspect you will need to go up 2” in prop pitch, assuming your current prop gets the 3.0 to 4600-4800 rpm.

I swapped a 4.3 for a 5.0 on my current boat, kept the 4.3 drive and it’s 1.81 ratio...

What is your oil pressure at hot idle and under way. You want 10 psi per 1000 rpm. If the engine is still tight and make s40 psi at 4000 rpm then 30 wt is ok, if the bearing clearances are looser run...

It fits fairly tight to the shaft

Carbon wouldn’t cause that, if valves were stuck he wouldn’t have compression in that cylinder

Carbon wouldn’t cause that, if valves were stuck he wouldn’t have compression in that cylinder

Back to the OP, every well working, Alpha gen one or two I’ve had had at least 1/8” in and out play in prop shaft. Years back I asked my mechanic too as it doesn’t seem right. Zero side play on the...

Its not a shaft seal, it’s not supposed to touch the housing. The merc impeller kit cones with a fixture to slide the slinger down the drive shaft and correctly position the slinger just above the...

That rattling sounds a lot like the one in this video https://youtu.be/HRyOwnhQwgE

poster claimed head gasket was blown due to overheat and ,raking a small amount of water into combustion...

Coolant or water in oil turns it milky , cream colored, and tacky

This is how staged helps you - chevy used only two types of starters for all its engines . If you need to replace look under there for a straight or staggered bolt pattern order accordingly. Make...

Because you can’t get the alignment in spec. There’s only a couple of things that can go wrong

rear mounts collapsed evidence is the lack of alignment if front is all the way down like you are...