New boat owner has Overheating question

Knot Waiting

Senior Chief Petty Officer
Joined
Jun 23, 2006
Messages
761
I appreciate any input that someone could give me on this. I just bought my first boat [1989 Celebrity Crown LIne with a Mercruiser Alpha 1 I/O[

I was winterizing my boat today, hooked up the "earmuffs" to the sterndrive and started the engine. I then began running coolant through the system and everything seemed to be going ok. Then suddenly after about 3-5 minutes of operation the engine died (quick not even a suptter) and the temp warning light came on. I felt the engine block and it wasn't even hot to the touch. Then I pulled one of the coolant hoses from the intake (topside) and found nothing inside of it (ie: no coolant of water). The engine started fine about 20 minutes later and sounded alrignt but I was too afraid to proceed. Could anything have gotten damaged in the breif peirod enven though nothing seemd to be alarmingly hot? What did I do wrong? Could this be a faulty coolant temp sensor like on a car?
Please help I am new to this and don't want to wreck my boat already. Thank you very much for any advice - Logan


P.S. I did have never had a temp issue with this engine in the water.
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: New boat owner has Overheating question

What engine do you have?
Did you have the coolant hooked to the muffs? If not, where did you have the coolant hooked in at?
 

Knot Waiting

Senior Chief Petty Officer
Joined
Jun 23, 2006
Messages
761
Re: New boat owner has Overheating question

Its a 5.7 L, GM 350. She only has 275 engine hours on her. The muffs were hooked to and elevated (aproxamately 5 feet up) funnel that I pourd coolant into. There is no hose hook up available in my garage and the weight of the water seemed sufficient as it was being forced past the seal with the engine off.
I'd appreciate any advice you could offer Don, Ive read your other posts and you really seem to know your facts. Thank You - Logan
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: New boat owner has Overheating question

Without water pressure, don't expect that pump to pull up water from a funnel. I would guess you have raw water cooling, I would also bet money you need a new impeller after your overheat. You probably burned it up due to lack of water. Dumping coolant in a funnel, even at 5' won't do the job.
If you want antifreeze in your cooling system, try this.
Run the engine on a hose with plenty of water pressure, fog the engine while running.
After shutdown, drain the raw water cooling system (all of it) then backfill (with antifreeze) thru the hoses at the thermostat housing. You may have to remove the thermostat to fill the block properly
If you don't understand what I mean, and don't have a Merc service manual for your engine, we will expect you here in the spring complaining of water in the oil due to a cracked block because of improper winterization.
How much of this other stuff have you done?

Winterizing your engine and drive.

Winterizing your boats engine and drive is a lot of work. Not doing it or doing it improperly WILL be very expensive to fix , and that is also a lot of work.
Plan on giving yourself the full day to winterize your boat, and don't wait till the last minute to do the job. As difficult as winterizing can be, doing it when it's 35º outside, snowing or raining, windy and in the dark is not something you want to do.
Read and think about everything you are about to do before you start, and plan for it. Tools, parts, helpers, (oh yea) even if just to hand you stuff and talk with you. Make a checklist if it'll help.
All set? Here we go.

Before you start the engine, add fuel stabilizer to the fuel tank. If possible, put in the stabilizer on the last trip of the season and top off the fuel tank before you get to your driveway or where the boat will be stored. This will allow the stabilizer to mix completely in the tank.

You do have your Service manuals for the engine and drive handy, don't you?
If not you are looking for trouble.

A few things you will need to have:
Get all your parts together before you start. Filters, gaskets, o-rings, seals, etc.
Note: (Gaskets, o-rings, and seals are not reusable, they may look like it, but they are a one time use item. )
Look at your manual before hand and know what types of grease, oils, lubes, gear lube, sealers, fogging oil, etc. you are going to need and have them on hand and ready.
Have the tools needed to do the job. Including filter wrenches, alignment bars etc.
Plenty of rags and oil absorbent pads

1. Start by hooking up a corrosion inhibitor to the muffs inline with the water, an example would be the Salt-Away mixing unit. This will do several things. Warm and mix the oil for changing, and flush the cooling system if you have been running in salt or brackish water.
2. After running, change oil, filter.
3. Change fuel filter/s, be sure to check the contents of the filter. If there is around a 1/4 of the contents water, you should drain the water out of the tank. (That won't be covered here)
4. Check the antifreeze level and be sure it's in the proper temperature range. -35 degrees is a normal 50/50 mix of antifreeze and water.
5a. Remove the Outdrive. (Mercruiser, OMC, and Volvo DP-S and SX)
Check ALL the bellows. if any of them look weather cracked or seem excessively stiff or weak, replace them. A leaky u-joint bellows ruins gimbal bearings and u-joints and drives if allowed to keep leaking.
On Mercruiser, OMC, and Volvo DP-S and SX style drives check the engine alignment (If you are going to do your own work, you MUST have an alignment bar)
5b. For those with the Volvo 270 through 290 style drives. Remove the upper gear box and check the bellows and u-joints. The bellows are not as strong as the Merc and OMC bellows so replace them every couple of years just to be safe. If they go bad, you must pull the engine to change the intermediate bearings in the bell housing. Be sure you don't loose the shims between the upper gear box and the intermediate housing.
6. Check the gimbal bearing. Does it turn smooth? if not replace it. Check the u-joints do they feel smooth also? Any catches indicates they are worn and should be replaced. If ok, grease the zirks or pull the plugs (if equipped) and lube them.
7. Was there any gear lube in the bellows when you removed the drive? If so, the input shaft seal is leaking and should be fixed before reinstalling the drive.
8. Drain the gear lube from the drive and refill per manufacturers specs. ALWAYS use new gaskets and o-rings on drain, fill, and vent plugs and dipstick fittings and plugs, along with new gaskets and seals for mounting the drive back on the boat. Don't forget to remove the gear lube monitor (if equipped) and clean it. The gear lube will form sludge in the bottom after a couple of years. Clean it yearly and you won't have a problem.

NOTE: For those with Mercruiser Alpha drives. If you are planning on changing the impeller, now is the time to do it. Since you must remove the lower unit to get to the pump, no reason to put in new gear lube till it's done.

9. Remove the prop and check for any fishing line around the prop shaft (very common problem, even for those that don't fish), clean and grease the shaft with a good quality marine waterproof grease prior to reinstalling the prop. Any kind of grease is better than none at all. And if you remove your prop yearly, you should never have a problem with the type grease you use.
(DO NOT use Neversieze) it may be great for cars, trucks, tractors etc. but in the boating business we call it "Eversieze".
If you notice nicks, dings or bends in the prop blades, now would be an ideal time to send the prop out to a prop shop for repairs.

10. Reinstall the drive per the manual. (new gaskets and seals, right)

11. Check the batteries, is the acid level where it should be? Are they fully charged? A low charged battery can freeze and crack and make a very big mess.
Terminal ends clean and greased.

12. Start the engine, make sure the oil filter doesn't leak, fuel filter doesn't leak and the drive still shifts and run it till it warms up. All ok, GOOD. Now it's time to make it safe for cold weather.

13. Bring the rpm up to around 1500 rpm and start squirting fogging oil into the carb till the rpms drop and you are getting a lot of smoke out the exhaust. Then shut off the engine. If the engine diesels, restart it fog some more, make sure the idle is very low and shut it off again. You don't want water backed up into the cylinders from running backwards.

14. Disconnect the water and muffs and allow the water to drain out of the drive. Now get your manual and remove every drain plug on your engine, manifolds, coolers, heat exchangers, water pumps, and anything else that could have RAW water in it. DO NOT drain the anti-freeze side of a closed cooling system. Look at the book and make sure you have them all removed. Look around, missing one could cost you an engine block. Get a small screwdriver and probe inside every hole you remove a plug from. Make sure there is nothing blocking the water from getting out. Be sure the engine is also as level as possible so as much water as possible is drained out. Some of the coolers for oil and power steering can be drained by removing a hose easier than removing the plugs.
Put all the plugs back in and hoses back on.
If you are one of those that must use antifreeze instead of just draining, for whatever reason, you can fill the block and manifolds with a 50/50 water/antifreeze mix through the hoses to the manifolds and coolers and removing the thermostat and pouring antifreeze into the engine block. Many of the RV type antifreeze do not have corrosion inhibitors in them because they are meant to be used in the domestic water system.

15. Spray your favorite corrosion blocker on everything (except fiberglass).including the battery terminals. Turn the steering so most of the rod is extended, make sure it's clean and spray it with a light oil, turn it back and forth a few times spraying in between so it's well lubed.

16. Store the boat with the bow up and the drive down. If the drive is up the exhaust part of the drive behind the prop can fill with water, freeze and crack.......Not Good!
It's also a lot easier on the u-joint bellows to have it in the down position.

17. Shut off (Better yet, disconnect) the batteries. Tag the cables and wires so you know where to put them back in the spring (trust me on tagging them).

18. Don't forget the rest of the boat, this is only for the engine and drive. There is still the domestic water system and the head to deal with.
 

Knot Waiting

Senior Chief Petty Officer
Joined
Jun 23, 2006
Messages
761
Re: New boat owner has Overheating question

I was kinda thinking that but I wanted an experts opinion on it. I did do what you said though. I removed all the hoses and drained the water out (alot of water) then I poured some raw coolant into the thermostat housing and reassembled it. I also pulled the 4 seacocks out of the exhaust risers and removed the fuel/gasoline seperator. When I restarted the engine I did snub it with fogging oil and sprayed the engine down. I am still a little nervous that there might be some water trapped in the water jackets in the block. Would draining the system like I did clear these? Also I disconected the battery, greased every zerk, and changed the sterndrive oil.
As far as the impeller goes I got some instructions from Mercury and was going to change that too. They reccomend to do it seasonally!? Is that true? Anything else I need to do. We get pretty cold up here in Wisconsin, just want to be safer than sorry.

P.S. Sorry to keep botherin you with trivial questions but this is how you learn right? Thank You again - Logan
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: New boat owner has Overheating question

There is nothing wrong with replacing them yearly, but they should be ok with 2 seasons. Of course, if you see overheat problems developing, then the impeller is the first thing to check. It doesn't take that much to destroy one, and often (most) times you don't even see what may have caused the problem.

From your discription, I'm not sure what you drained. But you need to drain the block, and the manifolds if your engine is raw water cooled. Then fill things back up with antifreeze. I can't see what you did, and by your discription couldn't say for sure if you did it right or not. That's the reason for the manual. There are pictures, and diagrams of your system.
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,133
Re: New boat owner has Overheating question

then I poured some raw coolant into the thermostat housing and reassembled it.

Did you Remove the T-stat,..??..??.....

If Not, you Probably Winterized the Manifolds,+ Not the Block...........

(edit),.......
I just came back to Actually Read that post Don,.......
It's an Extremely Clear, Concise, Complete article,....
Very Well Done,.... You've covered about Any drive that's usually talked about here at iboats.....
Although I Don't Agree with the adding Antifreeze part of it,......
I'll be C&Ping it for others to see,........ It's a Great FAQ answer............

Thanks Don,..........
 

shelikesit

Petty Officer 2nd Class
Joined
Nov 23, 2005
Messages
171
Re: New boat owner has Overheating question

not to get off topic, and i dont plan putting my boat up for the winter, do they sell warmers for the outdrive and engine?

cover them both with blankets like the plants? seriously, i would really like to follow Don's concise steps but if its 30 on the weekend and a day later climbs back to 75......... the boat will go back out.

what do ya'll do down here?

i did keep the steps, they were to well written incase i venture north one day. which i honestly doubt will ever happen.
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,133
Re: New boat owner has Overheating question

From about Now til sometime in December,.......

I just Drain ALL the Water out of My Boat,.....
So I can continue to Go Boating.........
 
Top