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Water circulation problem


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Boat is 2000 sportster. Started winterizing it, connected fake a lake to hose to warm engine to change oil. Didn’t notice any particular problem.  Next, I put fake a lake hose into a full bucket, along with hose.  This is the way I got antifreeze into the engine last year, without issue. I noticed the engine isn’t sucking water out the bucket. This despite being well primed due to the previous direct connection to the pressurized supply from the hose. Last year it would empty the bucket pretty damn quick. 

I checked the transmission cooler strainer, nothing there. Checked the impeller, noticed some of the vanes have lost their spring, and not pushing against the pump body.  http://imgur.com/KunnC6i 

So I replaced it with the one intended for next season. Retested, same problem. I also don’t have much water coming out the exhaust, at least not as much as I remember last year. At idle there’s pretty much none. So it seems that there’s insufficient water circulating. I did let the engine get above 160 so the thermostat should have opened. But I’d expect a good quantity of water to be expelled out the back regardless of what the thermostat was doing?

Am I right in thinking the thermostat acts like a switch in that when cold, water path is from transmission cooler straight to exhaust manifolds, and when hot, the thermostat blocks that path and instead opens the path from the block, so water now flows out from the block into the exhaust?

Given I’m not getting water sucked out the bucket, little out the exhausts, and the sea water impeller pump is working, the transmission heat exchanger isn‘t blocked (I could easily blow through it too), what could be wrong?  Could it be the main engine pump? (I think no because water should flow freely out the exhaust with the thermostat cold).  Could it be the thermostat?  Again, I’m thinking it could be faulty, but whatever position it’s in, I should still get water sucked out that bucket, and out the exhaust.  Lastly, on the last run I noticed the raw water impeller was getting quite hot, not what I’d expect given it should have a healthy flow of cold water through it. 

On the lake all summer the engine ran fine. I did notice temp tending to creep up above 160 if it was left idling for a while, I’d say more than 5 mins. I put that down to just insufficient water flow, once engine speed was raised to say 2000 rpm it cooled back down pretty quick. 

Any ideas where to look next?  Thanks...

Edited by Dampsquid
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In the past I have solved the temperature creep with an impeller replacement.  When I do this it will suck out of the bucket.

Either your new impeller is bad, I have had that, or you are blocked somewhere.  One thing to check is the intake hose for debris prior to the impeller.  If that is clear......

Try unhooking a hose after the impeller and see if it will suck.

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Some progress...

Started at the thermostat, nothing untoward. Started working back towards lake intake... pulled hose between impeller and transmission cooler, tuned engine over will kill switch cord removed, no water!  Took impeller cover off, turned hose on connected to fake a lake, no water (didn’t crank engine from here).   Pulled hose off input side to impeller, no water! Pulled hose off hull fitting, still  no water... so you’d think the intake is totally blocked..?  Nope. Put a boroscope down there, it’s clear!

By jiggling the cup of the fake a lake around and getting in just so, I could get water to come out the hull fitting into the bilge. So it seems the fake a lake just isn’t working. 

Also, how is the engine getting enough water during normal operation?  It looks to me that when in the lake the water line is roughly at floor level, significantly reducing the static head that the pump has to work against. Seems that’s enough. 

What I still can’t explain is how the exact same setup worked perfectly last year , it sucked out a bucket at ground level while on the trailer without problem. 

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19 hours ago, Dampsquid said:

Boat is 2000 sportster. Started winterizing it, connected fake a lake to hose to warm engine to change oil. Didn’t notice any particular problem.  Next, I put fake a lake hose into a full bucket, along with hose.  This is the way I got antifreeze into the engine last year, without issue. I noticed the engine isn’t sucking water out the bucket. This despite being well primed due to the previous direct connection to the pressurized supply from the hose. Last year it would empty the bucket pretty damn quick. 

I checked the transmission cooler strainer, nothing there. Checked the impeller, noticed some of the vanes have lost their spring, and not pushing against the pump body.  http://imgur.com/KunnC6i 

So I replaced it with the one intended for next season. Retested, same problem. I also don’t have much water coming out the exhaust, at least not as much as I remember last year. At idle there’s pretty much none. So it seems that there’s insufficient water circulating. I did let the engine get above 160 so the thermostat should have opened. But I’d expect a good quantity of water to be expelled out the back regardless of what the thermostat was doing?

Am I right in thinking the thermostat acts like a switch in that when cold, water path is from transmission cooler straight to exhaust manifolds, and when hot, the thermostat blocks that path and instead opens the path from the block, so water now flows out from the block into the exhaust?

Given I’m not getting water sucked out the bucket, little out the exhausts, and the sea water impeller pump is working, the transmission heat exchanger isn‘t blocked (I could easily blow through it too), what could be wrong?  Could it be the main engine pump? (I think no because water should flow freely out the exhaust with the thermostat cold).  Could it be the thermostat?  Again, I’m thinking it could be faulty, but whatever position it’s in, I should still get water sucked out that bucket, and out the exhaust.  Lastly, on the last run I noticed the raw water impeller was getting quite hot, not what I’d expect given it should have a healthy flow of cold water through it. 

On the lake all summer the engine ran fine. I did notice temp tending to creep up above 160 if it was left idling for a while, I’d say more than 5 mins. I put that down to just insufficient water flow, once engine speed was raised to say 2000 rpm it cooled back down pretty quick. 

Any ideas where to look next?  Thanks...

Hook the garden hose to the fake a lake and turn it on full, icbw, but I think your burning up impellers trying to suck water out of a bucket with a hose to a fake a lake, don’t see that working as it would be difficult or  impossible  to lift water that distance with a dry raw water impeller. 

Edited by Bozboat
  • Like 3
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the whole antifreeze from a bucket theory is in general a bad one.  If you really want to fill the block with antifreeze, there's one right way to do it: drain the block, reinstall block drains, remove thermostat housing, fill with antifreeze, reinstall thermostat housing.

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8 minutes ago, formulaben said:

...or recirculate it at 160 degrees. ;)

Looks like an effective way to do it but a lot of work to set up. Do you have a pump between the bucket and the boat?

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15 minutes ago, minnmarker said:

Looks like an effective way to do it but a lot of work to set up. Do you have a pump between the bucket and the boat?

Looks like the pump is *in* the bucket.

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Yup, it's in the bucket. Sure, some effort to install the flush valve, but after that it makes winterization a breeze.

Edited by formulaben
Added link to valve
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On 10/7/2018 at 1:21 AM, shawndoggy said:

the whole antifreeze from a bucket theory is in general a bad one.  If you really want to fill the block with antifreeze, there's one right way to do it: drain the block, reinstall block drains, remove thermostat housing, fill with antifreeze, reinstall thermostat housing.

I do this, but I also drain all of the hoses.  Then I reconnect everything but the big J hose, and fill the antifreeze thru that one.

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I've decided to try a Perko flush device.  Order of operations will be:

Get engine up to temp on water, drain all water from petcocks and manifold, run on antifreeze until exhaust is pink, fog engine, stop & drain antifreeze (all hoses, petcocks etc.).  This is what I did last year, except is all from the fake-a-lake.  Last year I had good pink antifreeze coming out the drains.  My reasoning is by running the engine I'm displacing the most water possible.  After draining the antifreeze any fluid left in the engine will, worst case, be a mix of water and antifreeze, but now since it's drained it'll have expansion space if it does freeze.  Filling the engine statically via the J hose or thermostat housing is fine if I knew the internal geometry of the cooling passages, and I knew there was no place for water to hide... which of course, I don't.

If the Perko thingy proves less than satisfactory, my backup plan will be to remove the 'stat housing and pour antifreeze straight in.  I'm wondering:  if filled via J hose, are you going in the top of the hose and so to the engine's pump, or are you going in the bottom the hose (held up) and so into the thermostat housing?  The latter makes more sense to me... but I'm wondering if the thermostat needs to be open, and will it stay open long enough as cold fluid flows past it...

Edited by Dampsquid
typo
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Wish I could claim the idea as mine, but someone else here used PVC on the standard exhaust ports and made a temporary "FAE" for winterization in this manner.  I like it because there is absolutely no doubt the antifreeze is everywhere it needs to be and thermostat is wide open.  I know many people here never use anti-freeze but for me it is just simple peace of mind and cheap insurance. 

Side benefit is anti-corrosion properties of the antifreeze in the system all winter.

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40 minutes ago, Dampsquid said:

I've decided to try a Perko flush device.  Order of operations will be:

Get engine up to temp on water, drain all water from petcocks and manifold, run on antifreeze until exhaust is pink, fog engine, stop & drain antifreeze (all hoses, petcocks etc.).  This is what I did last year, except is all from the fake-a-lake.  Last year I had good pink antifreeze coming out the drains.  My reasoning is by running the engine I'm displacing the most water possible.  After draining the antifreeze any fluid left in the engine will, worst case, be a mix of water and antifreeze, but now since it's drained it'll have expansion space if it does freeze.  Filling the engine statically via the J hose or thermostat housing is fine if I knew the internal geometry of the cooling passages, and I knew there was no place for water to hide... which of course, I don't.

If the Perko thingy proves less than satisfactory, my backup plan will be to remove the 'stat housing and pour antifreeze straight in.  I'm wondering:  if filled via J hose, are you going in the top of the hose and so to the engine's pump, or are you going in the bottom the hose (held up) and so into the thermostat housing?  The latter makes more sense to me... but I'm wondering if the thermostat needs to be open, and will it stay open long enough as cold fluid flows past it...

^^^^ This is exactly what I've been doing for years.  Get the water and antifreeze in through a (1-1/4 x 1/2) T on the raw water line.  Warm it with water feed until the thermostat opens then shutdown and drain the manifolds and block.  Close the system up and run a bit of antifreeze into the V drive then shut the thru hull valve and start up right away (<5 mins. since shutdown) with RV antifreeze (the propylene glycol kind) feed.  Thermostat is still open.  Run 4 gallons through.  Run shower for a minute or so when the antifreeze container starts getting empty.  Drain manifolds and block again.  Put it all to bed.  I don't touch any hoses.

Probably overkill but it makes me feel good on those -20 nights.

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I leave the J hose connected to the circulation pump (bottom) and disconnect and fill from the thermostat housing (top).  That bypasses the thermostat and fills the block. 

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Update: Still problems!

I installed the Perko flush device.  When connected to the hose and city water pressure, I get water through the engine and out the exhausts no problem.  When I replace the hose with a bucket (now in the boat about 10" off the floor) it won't even siphon out the bucket!  In desperation I installed a faucet in the bottom of the bucket so now gravity is 100% on my side - straight shot down to the Perko.  Still no water sucked through.  Yes, I did have the little black adaptor thingy in place, and I did test the Perko prior to installation by blowing through it.

So it seems water only flows under city pressure (and our's is pretty impressive).  Without that pressure, nothing.  Could it be the main engine water pump has completely failed?  That's the only thing I can think of, but there's no odd noises at all, and if it is the pump it must have failed taking the boat to the landing when I pulled it off the lake for the season.  The impeller is still OK even though it's taken some abuse.

If anyone has an ideas where to go next with this, please do tell.  I'm stumped.

Thanks in advance.

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that would be the raw water pump not the engine water pump that could be suspect.

How does your impeller look after all that running with no water being pulled through?  Could be as simple as a burnt up impeller (though I find that they're more durable than people make them seem and they can definitely survive a little dry running).

If you are dry though I would expect gravity feeding through a garden hose to be tough for the raw water pump to prime.  Did you blip the throttle a little to try to get some suction going?

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50 minutes ago, Dampsquid said:

I installed the Perko flush device.  When connected to the hose and city water pressure, I get water through the engine and out the exhausts no problem.  When I replace the hose with a bucket (now in the boat about 10" off the floor) it won't even siphon out the bucket!

Unless they changed their design the Perko doesn't have a check valve going back towards the raw water intake, so it will never "prime" without pressure.  Their own instructions say to close the raw water intake valve...many of these boats don't have that valve.  This is why I went with a 3-way valve for my flush.

Having said that, I've never had luck sucking in fluid, so I use a ballast pump to push the fluid up to the flush valve and into the system.

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1 hour ago, Dampsquid said:

Update: Still problems!

I installed the Perko flush device.  When connected to the hose and city water pressure, I get water through the engine and out the exhausts no problem.  When I replace the hose with a bucket (now in the boat about 10" off the floor) it won't even siphon out the bucket!  In desperation I installed a faucet in the bottom of the bucket so now gravity is 100% on my side - straight shot down to the Perko.  Still no water sucked through.  Yes, I did have the little black adaptor thingy in place, and I did test the Perko prior to installation by blowing through it.

So it seems water only flows under city pressure (and our's is pretty impressive).  Without that pressure, nothing.  Could it be the main engine water pump has completely failed?  That's the only thing I can think of, but there's no odd noises at all, and if it is the pump it must have failed taking the boat to the landing when I pulled it off the lake for the season.  The impeller is still OK even though it's taken some abuse.

If anyone has an ideas where to go next with this, please do tell.  I'm stumped.

Thanks in advance

I hate to just go @nitrousbird on you, but you are headed for disaster as this thread is just a foreshadowing of your thread next Spring. “need a new block”  

Formulaben, Michigan Border and SD are absolutely correct.

 

  • Like 1
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1 hour ago, Dampsquid said:

Update: Still problems!

I installed the Perko flush device.  When connected to the hose and city water pressure, I get water through the engine and out the exhausts no problem.  When I replace the hose with a bucket (now in the boat about 10" off the floor) it won't even siphon out the bucket!  In desperation I installed a faucet in the bottom of the bucket so now gravity is 100% on my side - straight shot down to the Perko.  Still no water sucked through.  Yes, I did have the little black adaptor thingy in place, and I did test the Perko prior to installation by blowing through it.

So it seems water only flows under city pressure (and our's is pretty impressive).  Without that pressure, nothing.  Could it be the main engine water pump has completely failed?  That's the only thing I can think of, but there's no odd noises at all, and if it is the pump it must have failed taking the boat to the landing when I pulled it off the lake for the season.  The impeller is still OK even though it's taken some abuse.

If anyone has an ideas where to go next with this, please do tell.  I'm stumped.

Thanks in advance.

The boat creates pressure into the raw water intake just by sitting on the surface of the water.  It is floating by displacing the water, and the water is trying to go up the raw water opening before the boat is even running.  So the lake water is pressurized, as is your municipal water.  You are drawing a vaccum when sucking it from the bucket, and it's not meant to do that.

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2 hours ago, formulaben said:

Unless they changed their design the Perko doesn't have a check valve going back towards the raw water intake, so it will never "prime" without pressure.  Their own instructions say to close the raw water intake valve...many of these boats don't have that valve.  This is why I went with a 3-way valve for my flush.

Having said that, I've never had luck sucking in fluid, so I use a ballast pump to push the fluid up to the flush valve and into the system.

Mine does have a check valve. Without it water would have spewed backward out of the inlet through the hull fitting onto the ground. A three way valve would have been perhaps a better alternative, I bought the Perko as the easy option. The instructions do indeed mention closing the sea-c*** - when flushing if the boat is in water. Presumably because there’s static pressure from lake water present in that case. 

Edited by Dampsquid
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1 hour ago, Michigan boarder said:

The boat creates pressure into the raw water intake just by sitting on the surface of the water.  It is floating by displacing the water, and the water is trying to go up the raw water opening before the boat is even running.  So the lake water is pressurized, as is your municipal water.  You are drawing a vaccum when sucking it from the bucket, and it's not meant to do that.

Agreed, to a point. Since the intake is below the water line this is true. But when stationary the water will only go up the tube to the same height as the waterline. In my boat that’s approx floor level. The impeller then needs to lift the water the additional height to the thermostat housing.  With the bucket connected to the Perko, the bottom of the bucket is already above floor height, plus the extra pressure from the water in the bucket, say an additional 10-12” of head... I’m already above the impeller height, meaning it has less work to do than when sitting in the lake.  There’s a huge difference between any static pressure in the inlet pipe from the lake versus that of the city supply  

Notwithstanding all of the above... last year it sucked a bucket dry in around 20-30 seconds,  through  a fake a lake, and while the bucket was on the driveway.  Something has changed, and not in a good way. :(

Others have said they’ve never had luck with the bucket idea. I wonder then how their boats stay cool on the water. My guess is they don’t sit idling for long, if they did, they’d over heat. It’s the extra (dynamic) pressure created in the system by the boat moving at speed that’s forcing water through the system. Just like the city supply has enough pressure to do the same apparently. 

Thanks for taking the time to reply.. :) 

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