Bad dewinterization- any thoughts

[Ruger761]

Well that throws out my guess on the starter and connections. Do you have jumper cables to do a quick test vs pulling batts out?


If it is hydro locking on you, water will drain into the crankcase with time as motor sits, releasing the motor to crank a few times until the cylinder starts to fill again. This increase compression to a point where the starter turns slowly until it fills enough and cant turn the motor anymore which can mimic a weak battery.

[GUY_RPM]

Well had not thought about that. Again oil is clean, no water present as far as I can tell. Just to be safe I am going to take batteries to Interstate store and let them check it.

[TeamAllen]

Maybe I missed it in there somewhere, but how old are the batteries?

[Joeprunc]

OP please do what Mike recommended. Try to turn the motor over by hand. Put a wrench on the crank bolt and see if you can rotate it. If it is hydrolocked you can easily replace the needed gaskets. If you keep trying to start a motor that is hydrolocked you easily can damage much much more, like a bent rod. I too hope that it is not hydrolocked, but please do this before you do anything else. The fact that it turned over before stopping makes me a little suspicious that enough water had drained out of the cylinder to allow for another cranking. Like Mike stated you will not be able to tell if there is water in the oil unless you drain all of it. Checking your dipstick will not let you know if you have water or not. I really hope your motor is not hydrolocked, but please check before anything else.

After verified try jumping your truck battery to the boat battery, see if there is enough juice to get it to run. I hope it is just your batteries, as deep cycle batteries are very very difficult to bring back from the dead.

[GUY_RPM]

Batteries are at least 3 years old as I was told they were new when I bought them. This hydro-locking thing has me scared, don't want to throw a rod. First thing I am going to do because I think it is a good place to start is pull the batteries and have them checked. If both batteries show bad I feel like I will have found the problem. I am going to start there and will let you guys know what I find tomorrow.

[Joeprunc]

Sorry don't mean to scare you, I just like trying to avoid any additional pain by taking a little extra time upfront to address an issue.

[boatwakes]

FYI everyone, pull the spark plugs BEFORE rotating the motor via the crank bolt to check for hydrolock, it should then rotate with less than 45 ft/lbs of torque. Every motor we've ever had to diagnose from a lock up has spilled water out when we pulled the plugs too. If you get your plug wires mixed up , here's the chevy firing order: 1-8-4-3-6-5-7-2 and the distributor rotor spins clockwise.

And to Guy, be sure when you restart with known good batteries that your volt gauge is reading at least 12volts but should show more like 13+volts with the engine running. If not, rev the engine to upwards of 1200rpm and then return it to idle. Some of the mercruiser alternators have a slow to activate excite wire which will "excite" with the increase in rpm when they won't at idle. If your voltage is under 12 even after following these steps, your alternator needs to be replaced.

[boatwakes]

FYI everyone, pull the spark plugs BEFORE rotating the motor via the crank bolt to check for hydrolock, it should then rotate with less than 45 ft/lbs of torque. Every motor we've ever had to diagnose from a lock up has spilled water out when we pulled the plugs too. If you get your plug wires mixed up , here's the chevy firing order: 1-8-4-3-6-5-7-2 and the distributor rotor spins clockwise.

And to Guy, be sure when you restart with known good batteries that your volt gauge is reading at least 12volts but should show more like 13+volts with the engine running. If not, rev the engine to upwards of 1200rpm and then return it to idle. Some of the mercruiser alternators have a slow to activate excite wire which will "excite" with the increase in rpm when they won't at idle. If your voltage is under 12 even after following these steps, your alternator needs to be replaced.

[GUY_RPM]

Bad news, had both batteries checked and both were good. It is at a shop now and he said he would pull the plugs to check for water. Next question is how much work does it take to change the seals, kind of curious as to what type of money I am looking at?

[Ruger761]

Ah man that is not the answer we wanted to here. Was really hoping for bad batts.

It kind of all depends on what is wrong and the full extent of the damage. If water is getting in, it can be any where from blow head gaskets, bad/cracked heads, cracked/rusted exhaust manifolds, to a cracked block. So without fully knowing the extent of the damage, just throwing a really rough number out there $500-4000. Parts can add up but labor adds up very fast.

What all steps did you do to winterize the motor last fall?

[GUY_RPM]

Ran motor on fake a lake to get motor hot. Pulled plugs to let water out. Bought a pump that pumped RV antifreeze from huge 5 gallon jug to fake a lake, started motor until I had a good stream of antifreeze coming out the exhaust.

[Ruger761]

hmm your meathod should have been fine in my opinion, long as you didnt miss a plug somewhere, but even then the antifreeze should have mixed enough to keep you ok. So I wouldnt think it was a freeze issue. I assume in KY you are in fresh water not any kinda brackish water that would promote early rusting? It will be interesting to see what the shop says on it.

Trying to think of other possibilities if it comes back and its not a hydro issue. Did the starter stick/hang in when you started it the first time? would have sounded very bad kinda growling and can make for what would seem to be a rough idle. This in turn would basically burn up your starter, so when you tried to start it the second time it cranked a few times until the starter finally died.

[GUY_RPM]

Just would like to say thanks to all of you for your help in diagnosing the problem. I enjoy the time I spend on this site with my Tige brothers.

[kko]

Being its a mercruiser the most common cause of your concern and its VERY COMMON is the upper starter solenoid. About $20.

http://www.jmsonline.net/710-89-9615...FVJp7AodGXEAkg Should look something like this.

[GUY_RPM]

Bad news, it did have water on top the cylinders. At this time my mechanic is thinking cracked head, riser or manifold. Any thoughts? I hope since I was able to shut it down before it shut itself down that maybe I averted any major damage to the motor itself?