5.0GL water intrusion into cylinder 1

[mikeneal]

I have a 99 5.0GL with a fair amount of time on it. (~1500 hrs). All salt water.
Was away this weekend and boat started hard at sandbar, I hoped was low battery from stereo. Checked oil when running back (was about 2 hrs north of condo) oil looked clear. Boat sat overnight in slip and this morning was hydro locked. Cylinder number one had fair amount of water in it. Sprayed wd40 in it and got towed to ramp. Compression test shows 175psi in that cylinder and about 150 in others. (Last time I checked was about 150 in all.) Maybe #1 is higher cause I hosed it down with wd40. Manifolds and risers are about year old GLM, I had both risers off about 2 months ago to do steering ram . But has been fine for about 50-60 hrs since it was apart. Boat didn't overheat, think there is chance it is just riser gasket? Seems like center cylinders would be first to get water but maybe those exhaust valves were closed? I guess tomorrow rip manifold and riser off and go from there. Do people make block off plates to pressurize them?

 

[mikeneal]

Worked on it this week. Removed the exhaust with riser intact and filed it wait water and let it sit and it stayed dry. Then rigged up pressure gauge to block drain and pumped water to riser water feed hose and plugged other side. . With about 10 psi saw the leak. Water leaking into exhausted valve area around the guide . So it seems for sure I have cracked head. Halfway thinking about doing top end but with 1600 hrs of salt water maybe a new long block is proper route.

 

[jerryjerry05]

Yup you wore that puppy out!!
​If your gonna use it as much as the old one??
Maybe think about a closed cooling system.
Include the manifolds too.

 

[mikeneal]

Got the drive off, admittedly it had been three years but wholly crap the trim pin was lockeddddd". Heated and beat it and wouldn't budge. Ended up drilling and tapping the end it and using sections of pipe and grade 5 bolt to make a puller. Now I found oil in the bellows too.

 

[Senior B]

When I was getting water intrusion, it was from the intake manifold gasket on the right side. Manifold bolts were very loose.

 

[mnjjansen]

What's your current status ? You didn't seize it right and you were within 24 hours of discovery ? Did you pull the engine apart or not or did you go straight away for a long block ? Despite the reasons outside the engine block, what about the block itself affected by the intrusion (cylinders, pistons, camshaft, bearings) ?

 

[mikeneal]

I bought new long block and swapped everything over. To fit in and out of my particular boat the manifolds and risers have to be removed. Local shop set it in the boat and aligned it for me and now have to assemble exhust and rig, For curiously sake took old heads off and the cyilnders had some wear and water jackets in the bloxk had some corrosion but not as bad as I would have thought.