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Tan, MerCruiser Certified Technician
Category: Boat
Satisfied Customers: 11077
Experience:  40 yrs. experience with complete engine repairs both inboard/outboard and MerCruiser Certified Technician.
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I have a Chapperal 250 signature with a Mercruiser 350

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i have a Chapperal 250 signature with a Mercruiser 350 engine. There are only 260 hours on the boat.
JA: Sometimes boat issues seem like they'll be really complicated, but end up being easy to fix. The Marine Mechanic I'm going to connect you with knows all the tricks and shortcuts. Tell me a bit more about what's going on so the Marine Mechanic can help you best.
Customer: Last Saturday when we used the boat, as we were docking, the engine sounded rough and it sounded like a rattling in the engine compartment. We docked without any problems and shut the engine.
JA: Is there anything else the Marine Mechanic should be aware of?
Customer: 15 minutes later I tried to start the engine and it was frozen.(locked).

Hello, I'm Tan. Welcome to JustAnswer. I'm reviewing your question and will reply momentarily.

This sounds like a hydro lock condition. Have you removed the spark plugs and checked for water? What happens is the riser or manifold will start leaking. The water will leak into the cylinders causing rough running. Then when you shut engine down the water continues to fill the cylinders. Then when you go to start engine it won't turn over. This is due to water in the cylinders. You can't compress water.

Does this sound like what happened?

Customer: replied 1 month ago.
What is the fix?
Customer: replied 1 month ago.
I am not mechanical. All of my service is done at my marina. I purchased the boat there. They usually take good care of me. The head mechanic was on vacation this week. a technician took a look and is recommending new valves and lifters at a cost of $4500. The engine only has 260 hours.

Replace manifolds and risers. First disconnect water lines going to the manifolds now remove spark plugs blow all the water out of the cylinders. Squirt some oil in each cylinder now turn engine over to lubricate the cylinders.

Have you removed the spark plugs yet and removed any water?

You need to do this as soon as possible. If you don't do this immediately the engine could seize.

No don't go that route. You can get a long block for less than that. Here is a link to a complete long block.

Post back with findings and questions.

Customer: replied 1 month ago.
I'd prefer continuing in writing
Customer: replied 1 month ago.
What is a long block?

No problem. Did you open the link I sent you?Open that link and it will tell you everything that comes with the engine.

Why did the tech say valves and lifters? If the lifters are damaged then the crank and crank bearings will be damaged also. Is the engine oil full of water?

Customer: replied 1 month ago.
I don't know about water in the engine. There was no water in the engine compartment when I checked it at the time of the incident. I live 2 hours from the marina so I couldn't get there. I was dependent on having someone diagnose the problem accurately. That is the purpose of me going there tomorrow.Do you think the time to reverse the hydro lock has been exceeded?
Customer: replied 1 month ago.
Are you still there?

Is this boat used in saltwater? If yes then the engine is most likely already seized. The cylinders will be rusted causing the pistons to seize. When the tech said valves and lifters this indicates to me the engine has water in the oil causing lifter failure. That would be the only reason for replacing lifters. If that is the case then the bottom end crank and all bearings will be damaged also. This is why I suggested a long block. You will get all new parts that are damaged in this motor now.

Customer: replied 1 month ago.
I am not 100% sure what the tech said. I may be mistaken about valves and lifters.With only 260 hours on the engine why would this happen. I would understand if I had 500 hours but not 260

It wouldn't normally but if you got water in the engine that would be a reason to have the valves done.

I am basing my diagnosis on your symptoms and what the tech said.

Customer: replied 1 month ago.
We had the boat out on the water Saturday for about 2 hours. There were no issues until we got close to the marina. Noting was unusual to even cause
Water to get in the engine. There wasn't any water in the bilge when I check the oil and drive fluid when we're docked.
It is saltwater by the way.

You said engine started running rough and it was making noise. The water would have gotten in the engine through the exhaust. What year is the boat?

Customer: replied 1 month ago.
2008. All maintenance was up to date.
Several weeks ago there was a leaky
Seal in the drive fluid system. The seal had to be replaced. Did that have anything to do with this problem?

The drive shouldn't cause engine to run rough.

What seal was replaced?

Did the drive have water in it?

The manifolds and risers are way over due for replacement. The replacement period for risers is 3.5 to 4 years of age or 350 -400 hours of use or which ever comes first. The manifolds are 500-600 hours of use or 5- 6 years of age or which ever comes first.

This is the average life of these components. I worked on boat in Fla for 40 years. Your symptoms are riser and manifold failure.

Customer: replied 1 month ago.
Is the long block basically a rebuilt used engine? Will it work as well as the alternative that the marina was recommending.

Yes and this engine comes with a 1 years parts and labor. Does their engine come with this warranty?

Customer: replied 1 month ago.
Since I am not capable of installing the long block myself, I am dependent on the marina to do the work. Do you think the installation is going to bring the cost back to $4500?

You need to find out everything they are going to do for that price. Does that include a long block and new manifolds and risers removal and replacement?

Customer: replied 1 month ago.
I will know tomorrow.
I was thinking of getting another boat and trading this in. Do you think I need to fix this first? Can I negotiate the repair with a
Purchase? Your thoughts?

You will definitely have to get this one repaired.

They won't give you much as is. You would be better off repairing this one and selling it to an individual with new motor. Trade ins they really take advantage of you and really give you way under market value.

They are not going to do you any favors with a trade in repair.

For the amount you have used this boat it might be better for you to sell this boat and when you want to use a boat rent one.

Lack of use is the death of a boat. Renting is cheaper in the long run if you aren't a heavy boater.

You have used your boat about 29 hours a year.

Customer: replied 1 month ago.
There aren't many boat rental operations in NJ Most of them went under. You have many more in Florida.We actually use the boat most weekends in the summer through October. The weather on the weekends this year was not great. We normally stay in the bay as my wife doesn't like the ocean. In September I plan a full day trip Atlantic City or New York with friends.I appreciate your help tonight. I this whole thing is very stressful. I didn't expect this to happen since all Maintenance is done by professionals.Have a great evening. You have been extremely helpful.

Not a problem. Post back if you need further assistance or questions on the repair they are offering.

I hope I’ve provided the information you were seeking. If you are happy with my service, your 5-star rating at this time is most welcome. If you need more help, please let me know so l can continue to assist you.

Thank you...........Tan

Customer: replied 1 month ago.
I definitely will5 star all the way!!!!Thank you.

To rate click on the stars at the top of the page.

Thank you......Tan

Tan and other Boat Specialists are ready to help you
Customer: replied 1 month ago.
The final result of the problem was the marina service dept. was able to drain the water from the engine and lubricated it fully. The engine was running as a result of their action. The manifold and riser is being replaced at an approx. cost of $3,500 (down from $4,500). They will inspect the engine components (valves, etc.) when the old manifold is removed.
I appreciate your help in keeping my stress in check with your advice.
Thank you,
Scott Maynard

Glad you got the issue resolved. Your welcome. Let me know if I can be of further assistance.

Why so much for manifolds and risers. The manifolds run $335.95.

Then risers are $240.00.

Then say 4 hours labor. @ $100.00. That comes to 1551.90 add freight and tax. So say $2000.00 that still 1500 high.

Customer: replied 1 month ago.
Thank for the info. I will definitely have that conversation with the marina.

Your welcome.

Thank you......Tan