Overheating-gctid395688

[cwiert]

Im at the boat right now. I just limped back to the dock on one engine. The stbd side overheated. When the alarm when off, I immediately shut it down. I checked the outdrive, no bags or anything like that. A visual inspection of the engine showed nothing abnormal looking. Next, I will pull the impeller and look at that. What else would cause this? Thermostat? How would I even check that? Im not super mechanically inclined, but I try my best, so please speak slow and don't use big words. Thanks a bunch,

John

[Guest]

Check your impellars, whens the last time they were replaced? I replace mine every other year. The only issue you have if an impellar tore apart, is finding the chunks of rubber stuck around the engine. You gota get those out best you can, if thats what happened.

Thermostat is good to check, could be stuck shut. Its pretty easy to replace, but you need a gasket.

Check to make sure the obvious, hoses, etc. Make sure your oil looks good also!!

These are just ethe 1st things I would check off the top of my head, you can go further down the list depending on what you find. How hot did the motor get and is it closed cooling?



Be aware that your impellars are below the water line, you will get water flowing into the boat if you unhook the hose to them. You can lift the hose up, should stop it or plug it. Just a heads up!

[Guest]

Hi

I take from your profile you run on fresh water lakes?

Have you got a closed cooling system ?

Locate your hose that comes from your outdrive and disconnect where it enters the engine, turn the engine over for a few seconds and see if you are getting a good flow and go from there.

Found this might help :

http://www.perfprotech.com/store/art...-shooting.aspx

Good luck.

[cwiert]

Tha ks. Ill check that. Impellers were done beginning of last year. Open cooling.

[Guest]

spike2450 wrote:
Hi

I take from your profile you run on fresh water lakes?

Have you got a closed cooling system ?

Locate your hose that comes from your outdrive and disconnect where it enters the engine, turn the engine over for a few seconds and see if you are getting a good flow and go from there.

Found this might help :

http://www.perfprotech.com/store/art...-shooting.aspx

Good luck.

this is incorrect, he has a bravo drive, not alpha. On a bravo the impellar is mounted on the engine, not in the drive so this will not be viable. (well i guess he could do that, but the impellar is right there might as well inspect it).

On that note, impellars that new shouldnt have issues, "SHOULDNT" but we know how that goes. Check it out let us know what you find.

Also when this happened were you going slow, or were you on plane?

[dktool]

If you have had no noticeable increase in normal operating temperature prior to this event than my money is on a stuck thermostat or momentary blockage of the cooling intake.

Did you restart this engine after it cooled and try it again ?

You could have had a bag or other debris on the outdrive intake that dislodged and floated away before you raised it for inspection.

I have had that happen many times.

[Guest]

dktool wrote:
Did you restart this engine after it cooled and try it again ?

You could have had a bag or other debris on the outdrive intake that dislodged and floated away before you raised it for inspection.

I have had that happen many times.

I've also had similar problems when picking-up seaweed, mostly kelp after a storm. Restarting the engine in this situation will result in the engine temp dropping vary quickly to the normal operating temp

[cwiert]

dktool wrote:
If you have had no noticeable increase in normal operating temperature prior to this event than my money is on a stuck thermostat or momentary blockage of the cooling intake.

Did you restart this engine after it cooled and try it again ?

You could have had a bag or other debris on the outdrive intake that dislodged and floated away before you raised it for inspection.

I have had that happen many times.

I'm thinking this may be what happened.

I was on plane...3900 rpm when the alarm went off and I looked down and saw the gauge at 250 degrees. I immediately shut that engine down. I got back to the dock and checked for a bag or something...nothing.

At the dock, I removed the black hose from the impeller...this is the one that goes to the engine. I couldn't get the red hose off...the one from the out drive, and i didnt want to pry the hose off and break the plastic water pump housing...been there, done that before. So with just the one hose connected, I briefly started the engine to check for water flow and I quickly filled my bilge with water. (I'm in fresh water, btw). The pump was working just fine. I hooked it all back up and started the engine. The engine had cooled on its own to 175 degrees and as soon as I started it the temp fell quickly to 120 or so. I let the engine run and the temp got back up to 175 and stabilized. It didn't get hotter than that. So, all seems ok now, but im still a little worrisome. Hopefully it was just a bag.

If it was a temporarily stuck thermostat, how could I check that and or fix that?

[Guest]

you dont check, you just replace the thermostat. I would run her for a while see how it reacts, sure sounds like you had something get stuck on your drive.

On that note, 250 is too high, constantly watch your gauges and watch. I bet I sweep my gauges every 30-60 seconds, just like when im driving my car. Keep an eye on em, they can heat up fast. You want to avoid getting to temps that high as it can cause damage to the motor. Sounds like you shut her down fast so im sure your fine though.

[Guest]

Check your risers/manifolds next.

[cwiert]

orca wrote:
Check your risers/manifolds next.

Check them for what? Cracks?

[cwiert]

If it was a bag, im surprised the impeller is still doing its job. It doeznt take long for them to rip apart with no water suppy.

Im wondering if it was a faulty thermostat. I wonder if i sbould just replace both to be safe.

[smitty477]

I am trying to remember if you had a similar problem last season and if so was it the same engine?

If yes and if the engine is fine unless/untill you get past idle speeds then you may want to check for a collapsing hose.

A fexible hose that is mounted between the drive and the pump itself will be under a vacuumn. In certain cases they will delaminate internally and will block flow at higher volumes without you be able to see it - when the moter is shut off and then operated at lower speeds the volume is less and the problem does not appear.

So please check/replace the hoses that are on the vacuumn side of the pump - you can likely guess how I know this one.

BTW - we will be back up in your area August 1-4 in Hamburg cove with 25-30 boats in the club. (Some at Essex) We come in your cove for gas at times and will swing by in the dinghy and say hi if you are around.

Hope this helps

[Guest]

cwiert wrote:
Check them for what? Cracks?

Total or near total closure of water jacket due to rust.

[cwiert]

smitty477 wrote:
I am trying to remember if you had a similar problem last season and if so was it the same engine?

If yes and if the engine is fine unless/untill you get past idle speeds then you may want to check for a collapsing hose.

A fexible hose that is mounted between the drive and the pump itself will be under a vacuumn. In certain cases they will delaminate internally and will block flow at higher volumes without you be able to see it - when the moter is shut off and then operated at lower speeds the volume is less and the problem does not appear.

So please check/replace the hoses that are on the vacuumn side of the pump - you can likely guess how I know this one.

BTW - we will be back up in your area August 1-4 in Hamburg cove with 25-30 boats in the club. (Some at Essex) We come in your cove for gas at times and will swing by in the dinghy and say hi if you are around.

Hope this helps

No, I never had an overheating problem before. This is new. I took it for a 20 minute ride after dinner and all was normal. I may buy an extra thermostat and just keep in on board in case I have a sticky thermostat.

Sounds good about August. If I'm around I'll look out for you!