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57 Mercrusier stern Drive Hydrolock starting issues

faderbain

New member
"My boat was running fine had

"My boat was running fine had no issues at all, no starting issues, no running issues none. After About 4 trips this summer. I started it up ran it out of a no wake zone and throttled up, shortly after throttling up I had overheating alarm. I shut the motor off. restarted same problem. shut it off and used my trolling motor to trailer the boat. I took the boat into a Mechanic and they told me the Impeller was burned up. and showed me the burned impeller. I had them do some general maintenance and fixed the impeller..

On the very first trip out. about 3 days after getting it from the shop. I started it up ran it for 2-3 mins, and I had smoke billowing from the engine compartment. (no ALarms) I shut the motor off opened the compartment and it was 2/3 full of water. I ran the bilge pump and drained it. looking over the engine I found that a lower cooling hose had come unattached. I re-atttached it and started the motor. it started up and ran fine. I went up lake about 20 miles with no issues. I shut down the motor and did some fishing about 2-3 hours. When I went to start the motor. I heard a horrible grinding noise and the motor would not turn over. I assumed that the starter was fried since it got submerged in the water. I replaced the starter and had the same horrible grinding noise. I trailered the boat and took it back to the mechanic. They told me that one of the teeth was broke on the flywheel and that the motor was (hydro locked). they suspect that the starter was fine. they cleaned it up replaced oils, plugs etc. I took the boat back to the lake the next week, It had a little issue starting the first time. but started up and ran fine. I ran up lake about 20 miles. shut it down and let it sit for 3-4 hours and same problem, horrible grinding noise, motor wont turn over.

After taking it back to the repair shop, I took it out for a test run on a local lake, and it started up ok but it struggled the first time to start. ran for about 15-20 miles. trailered it took it back to the shop and they said they couldn't find anything wrong and it ran good at their shop. the boat sat at my house for about 3-4 weeks.
I took it to the lake. when I tried to start it, the same horrible grinding noise, engine wouldn't turn over. I took to a shop at the lake. he replaced the starter motor and told me there was water in the cylanders. I put it on the lake 10 mins after coming out of the shop. it started perfect. ran it about 40 miles up lake, stopped and started it 2-3 time but it never sat more then 5-10 mins. parked the boat at a different marina, got up the next morning and Wham same exact problem. the mech at the boat marine managed to get it to start after hand cranking it several times he told me that the new gear now had teeth missing on it. I ran the boat for about 10 miles, shut it down and never could get it to start agian, same horrible grinding noise. I removed the plugs and I can hear water draining from one of the cylanders as I crank it by hand.

the mechanic is claiming that the motor being flooded wouldn't cause anything like this. and that my problem stems from my intial over heat.

anyone have any idea's what could cause this kinda problem."
 
Sounds like you have a cracked

Sounds like you have a cracked manifold where water is leaking down through an exhaust valve and into a cylinder or two. Might have been caused by the over heat condition as the manifold temp sores due to lack of water.

You could have also blown a head gasket but i think that is less likely.... especially on that engine.

Time to have someone take the heads of NOW before the rust sets in and you need to replace or rebuild the engine.

Think you got some bad help on the front end. Those boys should have uncovered these issues before sending you away with the boat. Wish you luck.
 
"Of course, if you tore up the

"Of course, if you tore up the ring gear and or starter - those need to be addressed again as well... but are symptoms of the problem."
 
"I have same engine and overha

"I have same engine and overhauled heads recently.
What I can imagine on your problems.

< Verify missing teeth of flywheel first>
1. If some teeth missing and it arrives before first cylinder firing the starter can not keep turn the flywheel and the starter might make a horrible grinding noise. If this guess is true you can manually turn the crank little bit, just by-passed the missing teeth, by using the box wrench then you will be able to crank up at least next 360 degree.

2. Or, you can inspect teeth by your eyes if you remove the starter.

I hope this helps your thinking.
HaeWoon / Seoul, Korea / ’97 Monterey 256CR – Mercruiser 5.7LX
(Sorry, English is not my Mothers language)"
 
"It sounds to me that the shop

"It sounds to me that the shops you are dealing with are a bunch of MORONS!!!

It does not take a masters degree to figure out that if you have water in the cumbustion side of the engine you have a water leak!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

1.YOU have to remove both exhaust manifolds and have them pressure checked!
2.The engine needs a compression check done on each cylinder, post results.


Normally when you over heat an engine due to impeller failure there is a real good possiblity that you burned a passage in the head gasket.

Hydro lock is water in the cylinders period!! you need to find out where the water is comming from.

If you have broken teeth on the flywheel, the motor has to come out so it can be replaced.

That is my opinion."
 
"Steve:

You are getting gre


"Steve:

You are getting great advice. Since there was an overheat condition, inspect/replace the exhaust shutters due to them breathing fire from the exhaust instead of their normal diet of hot water. Take a look at the inside of the rubber exhaust couplers to see if they also were cooked by the flame throwing exhaust.

HaeWoon Lee;

Welcome aboard; there is nothing wrong w/your english."
 
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