Mac5

High engine temperature

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Hi all, I'm new to this site and new to the boating world in general. Just picked up my first boat last week (no experience with boats). I got a 1994 Malibu Echelon. I have a few questions for anyone willing to help. 

1.The temp gauge wasn't registering so I changed the sender.  It began to work but the temp was hitting about 210 today after about an hour on the water.  The boat has been off for about 2.5 hours and parked (its hot here, about 105 degrees outside) and the gauge still says 210 and the engine and all hoses are very hot to the touch. Is this normal or is this temp way too high? If too high, what should I check? 

2. On the back f the boat there are two small white pieces (one on the right, one on the left) with black wires/tubes attached. Both are broken.  What are these parts and how important are they? I have a picture but don't know how to attach.

Thanks!!  

Mac

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1) Change the impeller and thermostat.  They are relatively cheap and then you'll know you've eliminated the basics.

2) I'm guessing those are the pitot tubes which show your speed.  Pic below, one on each side of the exhaust:

IMG_0157.jpg

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The engine temp should be measured with the engine running. Not sure, but one way to read your post was to assume gauge showed 210 after being parked as in off?

temp will climb when you shut down and go back down when you start up

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Formula Ben- thank you for the reply. Yes on the "pilot tubes" that is what I was talking about.  Neither of my speedometers work.  This must be the reason why? (I have a fish finder that I've been using to tell the speed) but would like them to work. 

The guy I bought the propeller from said it was almost brand new but I see some dings in it so I'm not sure. How expensive are those two parts? Any recommendations on brands/models I should get?

I also saw somewhere that I could have a blockage in the water lines. Should I start to flush those hose lines? If so, which ones?

Thanks!! 

 

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Boz- the temp was at 210 while I was out on the water. 

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Did you get a high temp alarm? My 93 skier has a buzzer type alarm. Does anyone know the setpoint for this sensor? Is it 220 degrees, or?

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These engines stay warm a long time. How long about did it run at 210?

Steve B.

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2 hours ago, Mac5 said:

Formula Ben- thank you for the reply. Yes on the "pilot tubes" that is what I was talking about.  Neither of my speedometers work.  This must be the reason why? (I have a fish finder that I've been using to tell the speed) but would like them to work. 

The guy I bought the propeller from said it was almost brand new but I see some dings in it so I'm not sure. How expensive are those two parts? Any recommendations on brands/models I should get?

I also saw somewhere that I could have a blockage in the water lines. Should I start to flush those hose lines? If so, which ones?

Thanks!! 

 

1) look for a propeller repair shop.  For not much money they can do amazing work.   New propellers are expensive.

2) Consider a GPS speedometer.  They work well and are more accurate   http://www.nauticlaugic.com/Products.html

3) blockage:   look at the hose that goes from the raw water pump to the block.  there maybe a transmission cooler, really a small tube type radiator about half the size of an empty paper towel roll.  When the rubber impeller self destructs the pieces will get caught in the hose before the transmission cooler.

4) like ben said above, check the rubber impeller, replace the thermostat with a marine thermostat.  Yours maybe a 140 degree.   Or pull the thermostat, put in a pot of water and heat it up.  Use your wife's candy thermometer to measure temp when it opens and closes.

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My 93 skier (5.7 l comp skier carbed)  runs with a 140-degree thermostat and she's a tiger.  I truly think they were designed that way (unique riser gaskets). Plus I only run in salt water, where they say it is better to have that lower temp? Something about the salt does not get hot enough to fully dissolve? Or?

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Posted (edited)

14 hours ago, Mac5 said:

Hi all, I'm new to this site and new to the boating world in general. Just picked up my first boat last week (no experience with boats). I got a 1994 Malibu Echelon. I have a few questions for anyone willing to help. 

1.The temp gauge wasn't registering so I changed the sender.  It began to work but the temp was hitting about 210 today after about an hour on the water.  The boat has been off for about 2.5 hours and parked (its hot here, about 105 degrees outside) and the gauge still says 210 and the engine and all hoses are very hot to the touch. Is this normal or is this temp way too high? If too high, what should I check? 

2. On the back f the boat there are two small white pieces (one on the right, one on the left) with black wires/tubes attached. Both are broken.  What are these parts and how important are they? I have a picture but don't know how to attach.

Thanks!!  

Mac

Welcome to TMC and owning a boat.

1. Where are you located? There are many members here that are willing to help out in person if need it.

2. Do as  @Bozboat stated on the impeller and thermostat and also his 3rd item.

3.Most likely you have the Mercruiser, this should be helpful http://www.atlanticmobilemarine.com/service manual 5&57.pdf

4. You can go to Mercury's website, https://www.mercurymarine.com/en/us/parts-and-accessories/parts-catalog Click on the Launch Parts Catalog button and then use the serial number to look at all the parts for your engine too.

5. Use the search feature in the forum, it works well and there is a lot information. Or go to gooogle.com  and type in  site:themalibucrew.com "search word"  . This will search the site using google.

Good luck and enjoy the boat.

 

P.S. http://www.defender.com/product.jsp?path=-1|311|2349076|2349083&id=3092416 GPS gauge for under $90

Edited by footndale
added gps
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14 hours ago, Mac5 said:

Hi all, I'm new to this site and new to the boating world in general. Just picked up my first boat last week (no experience with boats). I got a 1994 Malibu Echelon. I have a few questions for anyone willing to help. 

1.The temp gauge wasn't registering so I changed the sender.  It began to work but the temp was hitting about 210 today after about an hour on the water.  The boat has been off for about 2.5 hours and parked (its hot here, about 105 degrees outside) and the gauge still says 210 and the engine and all hoses are very hot to the touch. Is this normal or is this temp way too high? If too high, what should I check? 

2. On the back f the boat there are two small white pieces (one on the right, one on the left) with black wires/tubes attached. Both are broken.  What are these parts and how important are they? I have a picture but don't know how to attach.

Thanks!!  

Mac

So, you turn on the key, and the guages activate, and you see your temp at 210, correct?  It is not uncommon for the temp to rise after it has been shut down, especially on a hot day outside.  Odds are when you start it, (in the lake again or with a hose water supply in your driveway) it will immediately drop back down.  Do you know what the temperature is of the body of water you were in?

I agree with the suggestion of a 140 degree thermostat.  Have you done stuff like that before?  When you take off the top plate that the thermostat was under the gasket will likely come apart in a few pieces.  Make sure your mating surfaces are completely clean before reassembly, or they will leak.  I usually use a wire wheel on a cordless drill.  Also, you will likely need to replace the gasket at the base of that big thermostat housing, that goes into the intake manifold.  Same thing - make sure the surfaces are clean.

I agree with the impeller, change it for sure.  There is one end that the water goes into that the pump that comes up from thru the hull.  The impeller pulls water in thru this end.  The other end goes into a hose that goes under the engine to the transmission cooler, that round long thing that was mentioned, this is where the water is pushed to.  At the end of that hose is the transmission cooler.  At the input end of the transmission cooler is a honeycomb-like screen, that can get plugged with debris.  That can certainly cause a high temp issue.  In fact, I'd check that spot before doing anything to the thermostat.  But either way - if you don't know the age of the impeller, then change it.  I change mine every two years.  I did it this year and the old one looked mostly good, but did have some signs of cracking.

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Wow you guys are awesome.  This is a great forum!! I'll do my best to answer the replies. 

We were on the water for about 3 hours and by about an hour and a half in the temp gauge got to about 210 degrees.  

Steve B- Good to know. Boat was running for about 3 hours. 1/2 of which was at higher than desired temps.  

Malibu paradise- the temp alarm never sounded.  I never reached 220 though. 

Boz- thanks again for the more in depth info. Very helpful. I've begun tackling the impeller changeout. The hose going from the raw water to the housing is being extremely difficult to remove. Thinking about cutting it off and installing a  new one.  

FootnDale- I'm in granite bay next to Folsom lake in Northern California (outside of Roseville/sacramento) Last week I noticed an echelon owner in citrus heights which is very close to me.  Can't remember who it was but I would love to connect with him. Thanks so much for the rest of the information!! 

Mich. Boarder- Great info! The boat was definitely running high when on the water and engine was running. I'm tackling the impeller change out and as I stated above one of the short hoses is extremely difficult to remove. It's a thicker type with no flex in it so its tough to pull off combined with the awkward position of where it's located.  This is just the beginning phase of "experience" though, I'd imagine one of you would have the skills to pop it right off. All part of the journey for me I suspect. 

I also removed the hose going into the housing of the transmission cooler (I think). I took some photos of the honeycomb screen that appeared to have some light blockage.  I removed the blockage (photo also) just not sure how to upload.  The photos look like broken pieces of impeller but it wasn't blocked all that much so I would be surprised if this is the cause of high temp. 

Questions:

1. Should I cut off that short hose going from raw water to impeller housing and install a new one because it is being so difficult to remove? Is it a special type of hose or the same as the rest (so long as I get the right size)?

2. Is there a chance that there is more debris inside the transmission cooler or other parts/hoses that I should be checking? Should I try and vacuum out the transmission cooler? 

Thanks guys! Awesome info!! I hope I addressed everyones responses. 

 

 

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I have a 2001 Sunsetter VLX monsoon, mine has been running on the high side for as long as I can remember, (180?) I recently changed the thermostat (160), but it still shows the higher temp all the time.  Sender?

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Changed thermostat and impeller... temperature shot up to 210 while I was leaving the dock. Did I install impeller wrong? 

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For parts go to www.skidim.com.

Also call them as they are a great resource!

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7 hours ago, Mac5 said:

Changed thermostat and impeller... temperature shot up to 210 while I was leaving the dock. Did I install impeller wrong? 

How quickly after starting the motor and leaving the dock did your temp get to 210? It should take several minutes to get there. If it jumped to 210 really quickly and before your risers got hot then there's a chance a sensor is off. Did you have a chance to pull the thermostat and test it? It's a pretty simple process. Also, what did the old impellar look like after you removed it? I doubt if you improperly installed the impellar as it's a pretty simple evolution. You just have to be careful not to overtighten the brass screws in the faceplate. Have you run it on a trailer? I would be curious to see how the water flow is coming out of the exhaust ports. 

You did right by checking the transmission cooler for debris. It's something that should be done annually as part of your winterization plus if you boat on a lake with a lot of debris it can get clogged fairly often.  

Concur with dlb in calling Skidim. They're great to work with, extremely knowledgeable and will send you a parts catalog for future reference. 

 

 

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jgates 237- The temp started rising immediately.  Within seconds it began to climb and within a minute it was over 200. 

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If you were only at idle it is possible pump did not prime and you need to bump the throttle to get the water flowing.  Another option is that your circulation pump has failed.

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When at 210, you should not be able to put hand anywhere on engine. Normal operating temp you should be able to place your hand on the risers and on the thermostat housing.

i would go back and think about this step by step, maybe run engine (idle and neutral only) on a trailer with a Waterhose or fake a lake

verify water flow out both exhausts (no blockage, could be an obstruction like a failing exhaust hose, broken baffle in muffler)

verify engine temperature with an infared thermometer or by the laying of hands

You can put your hand on the thermostat housing and actually feel when the thermostat opens

If water flow is good, raw water pump is good, thermostat opens, engine gets hot above being able to put hands on risers, pull the circulation pump. 

if you need more information on any of this, let us know. this is something you can fix

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Thanks Boz and Chuck,

I need to set up a fake lake or hose. Can you explain how to do that? 

In the front of the thermostat housing is a large hose that has a spring in it. Is the spring necessary? Could this be the culprit and if I change teh hose do I need a spring in it?  

I know for a fact water was running through the impeller housing becasue at first water leaked out of the thermostat housing.  That means I installed the impeller correctly right? 

Thanks, Mac

 

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Disconnect the inlet hose where it gets the raw water at the bottom of the boat. Put a garden hose in it and turn the water on.  This is the hose you wanted to cut. :)

You have mercruiser engine right? The thermostat housing should have a thermostat and and sleeve.

 

35127919140_0b1b0d64b9.jpgthermostat' by footndale, on Flickr 

 

 

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Progress has been made...I had to cut the raw water line to work on the impeller because the hose was old, stiff and practically glued to the inlet coming into the boat.  I replaced this piece of hose with a new hose of similar strength rather than just a rubber hose. 

I got the impeller installed and also disconnected and flushed out every single hose along with the transmission cooler.  I also installed a new thermostat and hooked up a fake lake in the driveway. I turned on the boat and within a 1-2 minutes the temp was over 200 and a few hoses became too hot to touch so I turned off the engine immediately. 

I took the boat to a local parts place/mechanic and showed him how I installed the thermostat. He verified it was correct (it's very easy to do).  He told me to take the thermostat out and run the fake lake. I went home and did as he suggested. The boat stayed cool. Started at 120 got up to 160 then began to drop back down as it idled.  Let it run for about 5 minutes.  

I then took the boat out with the family without the thermostat and it ran perfect and stayed between 140 and 160 all day (mostly at 160).  At this point I may just run it without a thermostat for the summer and then take it to a mechanic or dive into it again in the fall.  Thanks everyone for the great advice! While it was a pain the last few days it was all worth it because I learned a ton about my first boat. 

 

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What temperature thermostat did you install?

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Rednucleus- I installed a 160.  It ran hot during my fake lake test so i took it out. Used the boat today and yesterday with no thermostat and it ran perfect.  I bought a 140 and plan on putting it in, in the fall....it may or may not do the trick.   In the meantime I'll run with no stat. 

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Well, you are better off running cool than hot, but something is still wrong.  Your boat should run very cold with no thermostat.  So either your guage is wrong, or there is a restriction somewhere in the cooling.  I would just run it for now also, but keep an eye on everything, check inside your hatch regularly.

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