Volvo Penta 3.0 I/O Overheating. Brand New Engine!

[JayBird2015]

Just purchased my first Volvo Penta IO. It's a BRAND NEW "Michigan Motorz" engine put in last fall. She was run for a short period, less than an hour I was told by the seller. It was winterized by the marina and stored until the end of April. I closed the deal this past Monday. Took her out Monday for an hour. Everything worked perfectly. Took her out Tuesday. She overheated. :-( So hot that the Exhaust hose in the engine compartment melted. I replaced that and the overheat sensor on the elbow. Next, I went through the entire cooling system looking for issues. Checked the impeller, which was brand new. The seller gave me the old impeller for a spare.....It was in good shape yet.

I connected the garden hose to the inlet in the engine compartment. Started and ran to temperature at 1000 rpm.

I pulled the hose coming from the raw water pump to the thermostat housing....no water flow????? So I put the other impeller in. Now there is flow??? Going to check the part number of the new one and see if it's the wrong one.
Temp looked stable....did not spike as before. Stayed right in the 175 to 180 degree range....
Next, I put the water on the muffs. She started to overheat getting to the 200 mark after a few minutes. Again, I pulled the hose from the raw water pump and no flow????

I have read many posts in several forums and watched a few YouTube videos to gain more information about the drive. I have the Manual and have accessed the Volvo Penta Shop. Looked at system diagrams. I am looking at the Thermostat now. Thinking it may be getting stuck shut, and not exhausing the hot water. The manual and many posts advise against operating the engine without one. So I won't remove it till I have a replacement.

I also learned that the raw water pump is mounted on the front of the Volvo Penta engine, and not inside the outdrive. Looking for a bit of 'Ole Salt' wisdom here. I ran my 1986 Mercruiser 140 for 33 years and aside a few wear and tear parts, I never had trouble. In fact, my lil '86 is in my pole barn, but recently deemed "UnSeaworthy" because a rotted transome.

 

[Bondo]

Ayuh,..... Welcome Aboard,...... The raw water comes through some hoses, 'n fittings from the lower drive,....
Make sure that path is clear, so that the pump can pump water,.....

 

[Lou C]

Well here's the thing, on the OMC/Volvo style thermostat housing, the exhaust manifold(s) always gets water from the impeller whether the engine thermostat is open or not. So if both the exhaust and the engine are overheating as you have, it is likely that the impeller is not pumping water or its pulling in air. Because if the impeller was fine and the stat was stuck closed, then your engine would run hot but the exhaust would be normal temps. My experience with these stats is they rarely stick closed, they can not close all the way in which case the engine takes forever to warm up. One thing that can cause problems, is using an aftermarket impeller in an OEM housing, sometimes they are dimensionally off. Also, for it to pump properly the wear plate should also be replaced, if they are scored or the housing is otherwise worn, the whole works should be replaced. I change my Cobra impellers every 3-4 seasons, replacing the impeller, wear plate and internal cage, I re-use the housings as long as they are good.

Also: some muffs do not seal well enough on the drive water intakes to allow a pump on the engine to prime easily. Keep in mind that the impeller in an Alpha is right above the water intakes, so it can prime easier, and the impeller in a Cobra is just a bit higher, at the tail end of the upper gear housing. But on a Volvo or Merc Bravo with the engine mounted pump, the water has to travel up about a foot, then foward 3-4 feet to get to the impeller housing. I found the Tempo dual inlet ones come with rubber that is too stiff for the pump to prime on mine, I use the Merc/Quicksilver round ones made of softer rubber with the metal clamp so they can't fall off. These work a lot better. This will keep you from frying your new impeller when you start up on land. In the water hydrostatic pressure forces the water through the raw water intake passages up to the impeller so its less of an issue.

Dropbox

www.dropbox.com

see how much water is getting exhausted under the exhaust bellows and transom mount? this is what you should see...

 

[JayBird2015]

Well here's the thing, on the OMC/Volvo style thermostat housing, the exhaust manifold(s) always gets water from the impeller whether the engine thermostat is open or not. So if both the exhaust and the engine are overheating as you have, it is likely that the impeller is not pumping water or its pulling in air. Because if the impeller was fine and the stat was stuck closed, then your engine would run hot but the exhaust would be normal temps. My experience with these stats is they rarely stick closed, they can not close all the way in which case the engine takes forever to warm up. One thing that can cause problems, is using an aftermarket impeller in an OEM housing, sometimes they are dimensionally off. Also, for it to pump properly the wear plate should also be replaced, if they are scored or the housing is otherwise worn, the whole works should be replaced. I change my Cobra impellers every 3-4 seasons, replacing the impeller, wear plate and internal cage, I re-use the housings as long as they are good.

Also: some muffs do not seal well enough on the drive water intakes to allow a pump on the engine to prime easily. Keep in mind that the impeller in an Alpha is right above the water intakes, so it can prime easier, and the impeller in a Cobra is just a bit higher, at the tail end of the upper gear housing. But on a Volvo or Merc Bravo with the engine mounted pump, the water has to travel up about a foot, then foward 3-4 feet to get to the impeller housing. I found the Tempo dual inlet ones come with rubber that is too stiff for the pump to prime on mine, I use the Merc/Quicksilver round ones made of softer rubber with the metal clamp so they can't fall off. These work a lot better. This will keep you from frying your new impeller when you start up on land. In the water hydrostatic pressure forces the water through the raw water intake passages up to the impeller so its less of an issue.

Dropbox

www.dropbox.com

see how much water is getting exhausted under the exhaust bellows and transom mount? this is what you should see...

Ahoy Admiral Lou! Well I have better news to share today. Yesterday, I pulled the tstat and put it in a pan of boiling water. I dunked it several times and each time the stat opened, and then closed when I put cool water on it. Good Thermostat.

Next, I put the boat in the water. Fortunately the launch is just 5 minutes from my home. I left the Tstat out, just wanting to see if there was some other issue with the cooling system. I idled at the shore watching the temp gauge closely. You know what they say about watching pot of water boil.....lol. At shore, she warmed up pretty quick. Within 5 minutes, the temp was over 175. Frustrated....I pulled the impeller housing off again. Should have taken a couple pictures, but I found that not all the rubber blades were going in the same direction. And it looked as if it were backwards. I reinstalled the impeller....this time being super careful to make sure the blades were going the right way as the engine spins.

I took here out just for a minute to get up on plane at about 20mph. The temp dropped like a rock. In fact, It went all the way down to 120 degrees. The water temp is still pretty damn chilly up here in Michigan. In fact, there were ICE BERGS just a FEW DAYS AGO.... Well, maybe not that bad.

Next, reinstall the thermostat. Then take her out again. I am very happy to say the cooling system is working fine. The temperature leveled out at about 175 degrees and rose another 5 degrees at idle speed, but as soon as I was on plane, dropped right back to 175. As I waited for the trailer, I sat at idle, and the temperature stayed in normal range. I'm a HAPPY SEAMAN! Literally. I'm retired from the U.S. Navy Reserve, and have always loved being on the water. So this Memorial Day, I would like to thank the Lord Above for this little victory, and most of all, for the Men and Woman who paid the ultimate sacrifice so that we can enjoy the FREEDOM to go BOATING!

 

[Lou C]

That’s great to hear! I guess some impellers have to be installed that way. On my Cobra they have always been self-correcting. I also would lube with a bit of Dawn dish soap which maybe helps the blades flip the right way. Normally mine runs at 160, it might rise to 170-175 after coming off plane but will cool down to 160 after idling a bit.
BTW now you have to take a look at your charging system or battery. Mine usually runs at 14 bolts.

 

[Lou C]

PS
Here’s a trick I use to make impellers last longer, by avoiding a dry start on the first start of the season. Hook up the muffs & turn on the water. Then go up on the engine and disconnect the hose from the impeller to the stat housing at the stat housing. Now fill that hose with water with a bit of Dawn dish soap mixed in, then reconnect it. This will lube the impeller till the water gets fully through the raw water intake hose from the transom. I usally change them at 4 years I see just a bit of stretch marks on the blades then.

Also I have had good luck using OEM impellers....

 

[JayBird2015]

That’s great to hear! I guess some impellers have to be installed that way. On my Cobra they have always been self-correcting. I also would lube with a bit of Dawn dish soap which maybe helps the blades flip the right way. Normally mine runs at 160, it might rise to 170-175 after coming off plane but will cool down to 160 after idling a bit.
BTW now you have to take a look at your charging system or battery. Mine usually runs at 14 bolts.

Yeah...I've noticed that too. I'm going to connect my MultiMeter to it later and make sure it's charging okay. Haven't noticed any thing odd except the gauge showing 11 volts or so. Thank's Lou for your incite! Much Appreciated.

 

[Lou C]

You're welcome! If you need engine electrical stuff like starters or alternators I can recommend ARCO I have both on mine. Better than the off brand cheap stuff. If the battery is very weak and won't hold a charge, the charging rate in volts on the dash gauge will tend to be low. Check battery charge first.

 

[JayBird2015]

You're welcome! If you need engine electrical stuff like starters or alternators I can recommend ARCO I have both on mine. Better than the off brand cheap stuff. If the battery is very weak and won't hold a charge, the charging rate in volts on the dash gauge will tend to be low. Check battery charge first.

Great Advice. Thank You. Had her in the Water all day Monday. I believe she's good to go. I am so happy and excited. The 2005 is an UPGRADE from my 1986 FourWinns Freedom 16. I still have this boat. I brought her in for Outdrive Service. Got the dreaded call that she was dead. Well the wood support in the Transom has rotted. She was deemed Seaworthy. Plan to rebuild here this winter with my son's who both are AutoBody experts, and know fiberglass too. Plus they have access to guys that do it all the time. Doing the work myself is really the best. If I hired it out, it would have been 3-5K, and the boat is really not worth that. ENGINE under 400 hours and runs great. I have owned her since 1988, so 33 years of bliss.

I appreciate your Wisdom! HAPPY BOATING!!!!

 

[Lou C]

Love the lines of the classic Four Winns. Glad you’re fixing it and not parting it out. If I can ever find one I’d love a 201 Liberator (same hull as my 88 200 Horizon) with a 383 stroker and thru hull exhaust.

 

[JayBird2015]

THE SAGA CONTINUES. Couple weeks ago, had a Hose Clamp fail on the exhaust system and my bilge was filled with HOT WATER. Had the overheating issue under control, and planned to replace a sticking Thermostat. But the bilge flooding got to the Starter so damn it....nothing but a click when I turn the key. When I shorted across the solenoid and the starter motor only spun... didn't engage the Flywheel. SO. Ordered a new Starter. Also ordered a new Thermostat and Impeller for the cooling system. Oh by the way, the Power Tilt quit working. It tilts up, but not down. Swap out the relays an I could get it to tilt UP. WTF. Parden my french. So I ordered two new relays for the Power Tilt. Meantime, I can switch them from one socket to the other and either get the outdrive up <or> down. Oh Yeah. This really is a bugger.
So I put in this afternoon to test. I couldn't go more than a minute or two and she overheated again.....Not sure if you caught it......I had a 1986 Four Winns Freedom 16 for 33 Years and could trust this boat with all my heart. 33 years of BLISS and wonderful boating. Main Difference.....My '86 is a Mercruiser and BAD ASS! 140 HP of excellence. Besides Maintenance items she's been super reliable! Am I CRAZY?????? SHOULD I GIVE UP????? I am so Fed Up. Over 20+ hours wrenching on this engine. I want to SCREAM! And I have! A few times now. Looking for your Boating Wisdom again. I have an appointment on July 6 at a Marine Repair Shop. This week I am going to see if I can get it in earlier. I am beside myself right now. Tonight I put the Trolling Motor on her, and it brought us back to the launch. My Auxillary Propulsion Unit. APU. People laugh at me when I call it that. But on the U. S. NAVY ship I served on, they had TWO APU's that were extended from the Hull and used to help Maneuver and Dock. They were BAD ASS! I look for your incite and advise. I am not one to give up. But if this is a worthless cause, I'll sell it! Hate to do that 4 Sure

HAPPY BOATING MY FORUM FRIENDS!

 

[Lou C]

Have you found a reason for the overheats? Or do they come more or less randomly? There is a document (PDF) called Volvo Penta Overheat Diagnosis. See if you can find it & print it out and if you follow all the steps I bet you’ll find the cause.

 

[JayBird2015]

Have you found a reason for the overheats? Or do they come more or less randomly? There is a document (PDF) called Volvo Penta Overheat Diagnosis. See if you can find it & print it out and if you follow all the steps I bet you’ll find the cause.

Greetings Admiral Lou. I have an appointment at a Marine Engine Repair business. Will drop her off on July 5, and they will start on July 6. So besides getting the Power Trim/tilt working, I AM DONE!!!!!! I've wasted a whole month of precious weekends here in Michigan. We only get about 3 months....lol. Then the lakes FREEZE. This boat is certainly not a ICE BREAKER.....LOL. None the Less, I will look up the PDF and add it to my library. Always good to have information available in my hand when the stuff hits the fan.

CHEER'S!!! And Thanks for your incite!

 

[Lou C]

I'm sure you'll get it sooner or later. Definitely don't give up. These I/O cooling systems can be tricky. So you are fixing the old boat too? I hope so, I love the classic lines of the old FWs.
Couple of little things....on the Volvo SX (just like the OMC Cobra) there is a plastic fitting in the pivot housing, that the transom water hose connects to. Now if the boat's not winterized properly this can crack and suck in air, and lose water supply when the boat gets up on plane. To replace the drive has to come off but the pivot housing I think can stay in place. The key to having them not crack is when winterizing, put the drive down. Then disconnect your raw water intake hose at the stat housing, point it down to drain, then hold it up and fill it with -100 marine antifreeze till it runs out the water intakes on the drive. You can test for leaks from it by putting duct tape over the water intakes, tilt it up enough that you can see that hose that goes from the pivot housing to the transom mount (on the port side). Now disconnect that hose at the stat housing, and have a helper fill it with water. Watch to see if there are any leaks at the pivot where the hose connects. If so that is at least part of the problem.
Other thing the engine is supposed to be a reman correct or actually brand new? There is always a chance of a leaky head gasket, in that document it shows how to check for that. Basically you replace the hose from the stat housing to the manifold with a clear hose. Put the boat in the water and run it till the stat opens and see if there are air bubbles in that clear hose. If so the head gasket is allowing combustion gas into the cooling water which causes overheating. I got both of these tips from that document.
PS I used this test in a modified form to troubleshoot water in a cyl. At first I though exhaust manifolds (we are in salt water so you have to replace every 7 or so years) but tested them and they were not leaking. Turned out both HGs were blown from an overheat 3 years prior to that. This turned into a top engine overhaul, my first major engine job that I did myself. Still running well 4 years later.
The thing that convinced me to get only outboards in the future was that overheat. A hose popped off the p/s cooler behind the engine and flooded the bilge with salt water. Engine overheated and the salt water was up to the engine pulleys. Though I was going to have to beach the boat, and didn't even know at first where the water was coming in. But the engine died while trying to beach it and the water stopped coming in. Got towed in, though engine was trash but after replacing the burnt up rubber parts in the exhaust system it ran just as it always had, for 3 more seasons. After that, I did not want another inboard, where a cooling system failure could fill the bilge with sea water.

 

[JayBird2015]

I'm sure you'll get it sooner or later. Definitely don't give up. These I/O cooling systems can be tricky. So you are fixing the old boat too? I hope so, I love the classic lines of the old FWs.
Couple of little things....on the Volvo SX (just like the OMC Cobra) there is a plastic fitting in the pivot housing, that the transom water hose connects to. Now if the boat's not winterized properly this can crack and suck in air, and lose water supply when the boat gets up on plane. To replace the drive has to come off but the pivot housing I think can stay in place. The key to having them not crack is when winterizing, put the drive down. Then disconnect your raw water intake hose at the stat housing, point it down to drain, then hold it up and fill it with -100 marine antifreeze till it runs out the water intakes on the drive. You can test for leaks from it by putting duct tape over the water intakes, tilt it up enough that you can see that hose that goes from the pivot housing to the transom mount (on the port side). Now disconnect that hose at the stat housing, and have a helper fill it with water. Watch to see if there are any leaks at the pivot where the hose connects. If so that is at least part of the problem.
Other thing the engine is supposed to be a reman correct or actually brand new? There is always a chance of a leaky head gasket, in that document it shows how to check for that. Basically you replace the hose from the stat housing to the manifold with a clear hose. Put the boat in the water and run it till the stat opens and see if there are air bubbles in that clear hose. If so the head gasket is allowing combustion gas into the cooling water which causes overheating. I got both of these tips from that document.
PS I used this test in a modified form to troubleshoot water in a cyl. At first I though exhaust manifolds (we are in salt water so you have to replace every 7 or so years) but tested them and they were not leaking. Turned out both HGs were blown from an overheat 3 years prior to that. This turned into a top engine overhaul, my first major engine job that I did myself. Still running well 4 years later.
The thing that convinced me to get only outboards in the future was that overheat. A hose popped off the p/s cooler behind the engine and flooded the bilge with salt water. Engine overheated and the salt water was up to the engine pulleys. Though I was going to have to beach the boat, and didn't even know at first where the water was coming in. But the engine died while trying to beach it and the water stopped coming in. Got towed in, though engine was trash but after replacing the burnt up rubber parts in the exhaust system it ran just as it always had, for 3 more seasons. After that, I did not want another inboard, where a cooling system failure could fill the bilge with sea water.

Well Lou, I brought it to a Marine Repair Shop and they quickly diagnosed it to be a bad impeller housing. It was allowing air to leak and could not get good suction. I've had it running now for about 11 hours and no overheating. Plan on another 10 to 20 hours of Sea Trials before I can put some trust into it. Hope to be able to call this boat a SHE before the summer's done. Anyway, I really appreciate your responses. Years of experience I can tell. Happy Boating Admiral Lou!

 

[Lou C]

Great that you found what it was and that the solution was not an engine problem but a relatively simple one at that! Congrats!