Re: 1986 Merc inline 4 190hp, good or bad?
A-6 BN. Cool. I was a Marine EA-6B Prowler ECMO. Never went to the boat, although I did go to the boat
school.
You want to learn all about the 470, just read my recent posts. Here is my opinion. If I knew then what I know now, I would have avoided the 470 and looked for a 4.3l V-6 boat. There weren't many boats for sale when we went shopping. Most were either too big, too expensive, wrong type, or bigger pieces of crap. However, I'm now a 470 owner and that can't be changed.
I think nowdays our expectations are so high because even
Chrysler vehicles are built well compared to two decades ago. Some people heap scorn on any engine that requires any attention besides changing the oil. But you and I are used to doing thorough preflights and constantly scanning the gauges.
You know about the seal on the camshaft that could leak coolant into the crankcase. With two seals, if the first one starts to leak, you'll notice coolant dripping at the bottom of the timing chain cover before it starts leaking into the crankcase. Just keep and eye on it.
You've also been told about the problem with overheating and the head gasket. If it doesn't have the 4" heat exchanger, that upgrade will cost several hundred dollars. I've read that is a critical upgrade. Keep an eye on the temperature gauge.
Alternator conversion kit was easy to install, so don't sweat that. Replacing the starter with the engine in the boat is torture, especially if it's 98 degrees and you're stupid enough to ignore the shade of that big Magnolia tree in your front yard for half the day like I did.:redface:
Most doghouses drip water onto the engine in the number 3 or 4 piston area causing corrosion. When I pulled my head off, it wasn't usable. Too much rust. In fact, for some reason those two cylinders seem to be problem prone. I found coolant in the exhaust manifold of #3 and #4, so I suspect that either the exhaust manifold gasket was leaking or the gasket between the exhaust manifold and the coolant tank that sits on top was. You can add a gutter system under the doghouse to keep the crashing sea spray off the engine using large pvc pipe.
You'll hear a lot of complaining that there aren't parts for it, but I've been able to find all the parts I need for a complete rebuild, and if my block is flat, I'll be able to reassemble my engine with new pistons and bearings for $600 including the machine shop work.
I've found the engine easy to work on. I pulled the engine by myself with no problems. Very simple engine.
My only regret is that I paid too much for the boat to start with
, but hell it had a brand new pretty paint job and started and ran well, until I noticed the steam at startup
after I bought it. If you do make an offer, assume that you will need to pull the engine and rebuild it (if fact, assume that if you buy a 4.3L of a significant age).
I've learned a lot about what to look for in a boat and this was my first powerboat. I'll chalk up the extra I paid for the valuable knowledge I gained.
