Coolant water no flow, Beta 25

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FairweatherDave

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As the title says, flow seems to have suddenly gone from perfectly acceptable to nothing. There was some weed in the filter which I cleared and I checked the impellor and all was fine there. The pump is only two years old. What should I do next?
I guess the main culprit should be the heat exchanger tube stack, which I probably cleaned two years ago, maybe three. Anywhere else I should look?
How would I diagnose a failed water pump? (Presumably no blockages and no flow but anything else?)
Thanks for any advice.
 
FairweatherDave said:
As the title says, flow seems to have suddenly gone from perfectly acceptable to nothing. There was some weed in the filter which I cleared and I checked the impellor and all was fine there. The pump is only two years old. What should I do next?
I guess the main culprit should be the heat exchanger tube stack, which I probably cleaned two years ago, maybe three. Anywhere else I should look?
How would I diagnose a failed water pump? (Presumably no blockages and no flow but anything else?)
Thanks for any advice.
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exhaust elbow ???
 
Is your pump above the water-line. If so, could your filter now have an air leak stopping priming?
Did you completely remove the impeller to inspect. A bit of broken blade can block the H/E inlet/outlet cap.
 
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sailorman said:
exhaust elbow ???
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Thanks sailorman. Yes I was wondering about that. But assuming it is weed that has got past the filter you go to the next spot along. I assumed the exhaust elbow is more likely to be a symptom of progressive overheating than a pretty abrupt end of flow, but I must stress I'm no great mechanic...... Also the horror stories I have read about exhaust elbows sound a bit grim....
 
earlybird said:
Is your pump above the water-line. If so, could your filter now have an air leak stopping priming?
Did you completely remove the impeller to inspect. A bit of broken blade can block the H/E inlet/outlet cap.
Click to expand...

Yes, completely removed the impellor and inspected. But an airlock is something to consider
 
Exhaust elbow issues would not suddenly affect water flow. First thing to check is that water is coming into the system from the seacock or strainer, then coming from the pump to the heat exchanger. Just follow the normal flow of water and when it stops flowing your blockage/failure is at that point.

My money is on either an air leakage or failed impeller. A 2 year old pump is unlikely to be worn out or to fail suddenly.
 
Tranona said:
Exhaust elbow issues would not suddenly affect water flow. First thing to check is that water is coming into the system from the seacock or strainer, then coming from the pump to the heat exchanger. Just follow the normal flow of water and when it stops flowing your blockage/failure is at that point.
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There is no blockage to the pump. The pipe is clear. Obviously there is likely to be a blockage at the heat exchanger......Just curious how you check flow out of the pump without the engine running? (I suspect a dumb question :))
 
FairweatherDave said:
....Just curious how you check flow out of the pump without the engine running? (I suspect a dumb question :))
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There won't be any flow from the pump unless the engine's running. I did once check my pump flow on my B25 by temporarily supplying from a 25L container, fed from a hose-pipe. Beta quote 15 L/min @1500rpm IIRC.
 
Skin fitting? If these was weed in the filter, there may be a clod of it at the skin fitting. If you have a Vetus strainer, you can take the lid off and blow a dinghy pump down the tube to check. Otherwise the heat exchanger - if it was 2 or more years ago it came off then it needs doing anyway.

I took the exhaust elbow off my 14 year old 13.5hp Beta and it was absolutely clear. The bolts didn't really want to come out, so wish I hadn't bothered!
 
With mine it was the tube stack in the heat exchanger. Take it out and I bet you see the bottom half choked out. I'm guessing that this half gets hottest and cooks out the minerals.
Also after cleaning I made note of the strength of water flow in my clean strainer which has a clear lid. This flow washes against the lid which it didn't before so now I use that as a guide when the stack needs cleaning. P.S. now it's bbq season get hold of them wooden kebab skewers, cleans out the holes a treat.
 
Thanks Pye End Cheesey and earlybird, that's all good to know. No, there is definitely no blockage (now) at the intake. I could see the sunshine glow of Chichester mud. Heat exchanger is the favourite, but the reason I pose so many questions is it is all so much easier than getting to boat and trying it out:)
 
My Beta runs in crystal clear Scottish waters so blocking of the H/E tubes is not a problem. However, I've found that the stub for the outlet hose has gunged up badly. This is very adjacent to the anode and needs checking when the end-cap is removed. Could even be a broken lump of anode in your case.
 
FairweatherDave said:
There is no blockage to the pump. The pipe is clear. Obviously there is likely to be a blockage at the heat exchanger......Just curious how you check flow out of the pump without the engine running? (I suspect a dumb question :))
Click to expand...

Yes, loosen the hose clamp. Run the engine and pull the hose off quickly. Probably water will spurt out then you know the blockages is further downstream
 
earlybird said:
My Beta runs in crystal clear Scottish waters so blocking of the H/E tubes is not a problem. However, I've found that the stub for the outlet hose has gunged up badly. This is very adjacent to the anode and needs checking when the end-cap is removed. Could even be a broken lump of anode in your case.
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You want to see the weed in Chichester. Impressive! Returning to the dinghy chains at Nore Barn was almost unrowable. Put your oar into a clump and you don't get it back!
Thanks for the detail on the blockage points though. Looking forward to getting to stuck into the job. Mind you the best part of sailing yesterday was last night once the engine had failed tacking up Emsworth channel with the tide to Sweare Deep. Amazing for a Bank Holiday just one other boat (around 8-9pm). Mind you the squally 30 knot wind that came from nowhere around 4pm might have had something to do with it.
 
Well problem sorted. I cleared the tube stack/heat exchanger. There was some rubbish in there including a stub of pencil anode. About 10 % of the tubes were blocked, maybe less. Ran the engine but still no flow. Decided to go for the "Tranona" test :) and check the flow directly out of the pump but could not get the rubber section of pipe off. So I disconnected where the pipe goes into the heat exchanger. No flow. At this point I phone Beta (as the pump is two years old). Very patiently he says to check the filter and impellor (which I have done).....he assures me it can't be the pump from what I describe. So I go back to the impellor. And I spot a black lump sitting at the exit to the pump. My efforts to disconnect the rubber pipe have dislodged a piece of old impellor. Point is I have had the boat for nearly four years, have annually inspected or changed the impellor and it has always been intact. So I then remove the whole pipe between pump and heat exchanger and "hey presto" another huge lump of impellor. I blow on the pipe like a trumpet and out shoots some weed (so that was the final straw that caused the blockage). So these two large lumps have sat in that pipe for a long time. Guess I've been lucky!

PS When I tell this story to the family they seem remarkably unimpressed:)... They say "Cool story Dad, needs more dragons..........."
 
Glad you got it sorted. Always nice to find such a definite solution to a problem. I've fitted a water temp. gauge to my B25 since I feel that problems such as overheating can gradually ramp up, and when the over-temperature alarm sounds, then it's on the late side!
 
My Sabre has a Beta 16, the tube stack needs cleaning out twice a season without fail. When you stop the engine it ends up half full of hot salty water & the salt precipitates out. Then you find that the exhaust swan neck is so close to the aft tube cap that you cant remove the tube stack backwards unless you remove the complete swan neck assembly, And if you want to pull it out forwards you have to remove the alternator!. Bit of poor design here!
I have extended the swan neck from its flange straight back adding 4" of stainless pipe, this gives you easy clearance for what is essential regular maintenance.
 
With my lay out on the 25 I have enough space behind the exchanger to extract it ......but yes the alternator is in the way pulling the tube stack out forwards. Interestingly I was just looking at a picture of a new Beta 25 and it looks like they have increased the diameter of the pipe between the pump and the heat exchanger quite significantly. (My heat exchanger has the single bolt on the cap at each end. (Will confess I found it quite a challenge getting the O rings perfectly fitted.... I'll have to practice yearly :)).
 
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