PosessionSound26PC
Petty Officer 3rd Class
- Joined
- Sep 21, 2020
- Messages
- 76
Back in September I posted about a possible seized starboard Merc 4.3 motor on my 1989 Formula 26PC, link here:
At the time, both the shop where I store my boat and myself thought it was the motor and they quoted ~$10k for a new motor R&R. With suggestions from this forum, I decided it was cheaper to do it myself but wanted to verify the problem during this last winter. So I did the following:
1. Removed and/or disconnected all accessories, including risers, exhaust manifolds, wiring, plugs and cables, carb, etc. I would have to do all this for swapping the motor anyway so no harm done.
2. I was also trying to figure out why the motor would not turn w/ a breaker bar on the crank shaft. As I tore off the riser and exh manifold on the right side of the motor (looking aft), I noticed the riser was very rusty and in need of replacement, but also a tiny bit of rust down the no.3 exhaust passage (VERY little, like a few tiny spots down the tube). I thought maybe water had gotten into no.3 cylinder and seized it up.
3. I tore off the intake and the head on that side. The intake was spotless. The head was spotless except for a light rusting around the exhaust valve on the inside of the cylinder.
4. No rust was evident on the inside the cylinder itself. That piston was near TDC but I could see enough of the cylinder wall to realize that it was unlikely this was the source of the problem - the wall was completely shinny and not a spot of rust anywhere. When winterizing in 2019, I had sprayed a good deal of fogging oil down the carb's throat...
5. I tore off the exhaust on the other side as well - no rust anywhere, plugs were spotless.
6. Tore off that head - no rust anywhere.
7. Motor still doesn't turn even w/o any drag from push rods and accessories.
8. Soaked cylinders w/ PB Blaster, let sit, and tried lightly tapping on piston heads w/ a block of hardwood between piston and hammer. Got about 1/8" of CW movement and no more. Backed it the other way w/ same method but only about 1/16", then stuck.
9. Today I decided to finally tear off the drive - should have done this first but I'm new to boats so... learn the hard way
10. Unbolted and pulled off drive (boat is in neutral - realize now I should have left it in fwd to help re-assembly...?)
11. Noticed the following: U-Joint was VERY rusty in appearance but moved freely. There was rusty colored grease all over the inside of the gimble housing, with chunks of solid grease and something gritty and white all around (at 65F here in the Puget Sound, the grease?). Gimble bearing LOOKED ok but didn't try to move it so not sure... does this need to spin freely for motor to turn? Don't think so since shaft can turn anyway, right? Shaft on outdrive was spotless/clean.
12. Also noticed that I could only turn the input shaft one direction by hand but that it turned freely. Is this normal in Neutral? Would think it should spin both ways... Stupid me didn't note which direction I was able to turn it...
13. The motor now turns easily with the breaker bar, feels like the port one.
What is going on? Is the drive shot if it only turns one direction in neutral?
I can't remember if I stated this in the original post above but toward the end of the 2019 season, I forgot to put the boat plug in one day and put the boat in the water. After starting the engines I did my usual engine bay check and saw a bunch of water in there, possibly as high as the oil pan. I quickly pulled the boat back on the trailer and out of the water. I ASSUME this could be the cause even though others have said it's not - that when the boat was back on the trailer, the water in there tilted backwards and somehow worked its way into that outdrive. I am not familiar with the seals, if any, in that area from the inside. Either that or the bellows seal had failed prior and was already leaking? It looked fine last I check it but it's hard to see the whole thing... didn't feel crusty, felt supple...
Any thoughts appreciated. I'm currently looking at putting the motor back together and letting the shop deal w/ the outdrives.
Formula 26PC - Possibly seized starboard Merc 4.3L
At the time, both the shop where I store my boat and myself thought it was the motor and they quoted ~$10k for a new motor R&R. With suggestions from this forum, I decided it was cheaper to do it myself but wanted to verify the problem during this last winter. So I did the following:
1. Removed and/or disconnected all accessories, including risers, exhaust manifolds, wiring, plugs and cables, carb, etc. I would have to do all this for swapping the motor anyway so no harm done.
2. I was also trying to figure out why the motor would not turn w/ a breaker bar on the crank shaft. As I tore off the riser and exh manifold on the right side of the motor (looking aft), I noticed the riser was very rusty and in need of replacement, but also a tiny bit of rust down the no.3 exhaust passage (VERY little, like a few tiny spots down the tube). I thought maybe water had gotten into no.3 cylinder and seized it up.
3. I tore off the intake and the head on that side. The intake was spotless. The head was spotless except for a light rusting around the exhaust valve on the inside of the cylinder.
4. No rust was evident on the inside the cylinder itself. That piston was near TDC but I could see enough of the cylinder wall to realize that it was unlikely this was the source of the problem - the wall was completely shinny and not a spot of rust anywhere. When winterizing in 2019, I had sprayed a good deal of fogging oil down the carb's throat...
5. I tore off the exhaust on the other side as well - no rust anywhere, plugs were spotless.
6. Tore off that head - no rust anywhere.
7. Motor still doesn't turn even w/o any drag from push rods and accessories.
8. Soaked cylinders w/ PB Blaster, let sit, and tried lightly tapping on piston heads w/ a block of hardwood between piston and hammer. Got about 1/8" of CW movement and no more. Backed it the other way w/ same method but only about 1/16", then stuck.
9. Today I decided to finally tear off the drive - should have done this first but I'm new to boats so... learn the hard way
10. Unbolted and pulled off drive (boat is in neutral - realize now I should have left it in fwd to help re-assembly...?)
11. Noticed the following: U-Joint was VERY rusty in appearance but moved freely. There was rusty colored grease all over the inside of the gimble housing, with chunks of solid grease and something gritty and white all around (at 65F here in the Puget Sound, the grease?). Gimble bearing LOOKED ok but didn't try to move it so not sure... does this need to spin freely for motor to turn? Don't think so since shaft can turn anyway, right? Shaft on outdrive was spotless/clean.
12. Also noticed that I could only turn the input shaft one direction by hand but that it turned freely. Is this normal in Neutral? Would think it should spin both ways... Stupid me didn't note which direction I was able to turn it...
13. The motor now turns easily with the breaker bar, feels like the port one.
What is going on? Is the drive shot if it only turns one direction in neutral?
I can't remember if I stated this in the original post above but toward the end of the 2019 season, I forgot to put the boat plug in one day and put the boat in the water. After starting the engines I did my usual engine bay check and saw a bunch of water in there, possibly as high as the oil pan. I quickly pulled the boat back on the trailer and out of the water. I ASSUME this could be the cause even though others have said it's not - that when the boat was back on the trailer, the water in there tilted backwards and somehow worked its way into that outdrive. I am not familiar with the seals, if any, in that area from the inside. Either that or the bellows seal had failed prior and was already leaking? It looked fine last I check it but it's hard to see the whole thing... didn't feel crusty, felt supple...
Any thoughts appreciated. I'm currently looking at putting the motor back together and letting the shop deal w/ the outdrives.
