Beta - heat exchanger stack stuck

[Thistle]

I removed the ends of the heat exchanger on my Beta 10 today.

After removing a surprising amount of old, corroded anode from the output end, I tried to remove the tube stack for cleaning. The manual glibly says "Remove the 'O' rings and pull out the tube stack." but mine seems well stuck in with a salty encrustation.

I've tried replacing one of the end-cap bolts and tapping that: no movement.
I've tried a length of timber on the end of the stack and hitting that: no movement.

I'm sure that once the stack is loosened, I'll be able to work it free. Any suggestions, please, for getting things started?

Once I get it out, what's the best way of cleaning the encrustation from the stack? Fernox??

 

[PetiteFleur]

Have you tried talking to Beta Marine? Always very helpful whenever I've talked to them. I cleaned out the 'holes' and the end caps on my Beta 25HP but didn't bother removing it completely. Cured the overheating!.

 

[orangemikey]

should come out easilly if regulary maintained, i take mine out every year to clean it, best thing to use is a fat skewer to clean out holes and soak it in viakal.
Mike

 

[neil1967]

If you find out how, please let us all know - I've tried a few times to get the stack out of my beta BD722 (20HP), with no success. I've tried brute force, as well as putting descaler in the fresh water system, but to no avail.

Neil

 

[NorthUp]

Try a hot air gun on the alloy casing- it will expand more that the brass tubestack.

 

[alahol2]

In case you have never seen it, this is what it looks like...
I had to tap it out with a wooden block the first time I did it, but since then it moves relatively easily. I would be inclined to be a little more vigorous with the 'tapping', the whole construction looks quite sturdy, though I guess you could split one of the soldered joints if you were too vigorous.
It's difficult to see where any corrosion could be sitting because the 'o' ring should prevent salt water getting to the gap between the stack and the casing.

 

[Tin Tin]

should come out easilly if regulary maintained, i take mine out every year to clean it, best thing to use is a fat skewer to clean out holes and soak it in viakal.
Mike

Is this common pratice with Beta Engines?
To be honest, apart from annual oil and filter change, I don't touch my Yanmar.
Seems to be all that's required.
If it ain't broke, don't fix it.

 

[PetiteFleur]

Is this common pratice with Beta Engines?
To be honest, apart from annual oil and filter change, I don't touch my Yanmar.
Seems to be all that's required.
If it ain't broke, don't fix it.

I only cleaned mine because the engine (4 years old) overheated last summer if I ran the engine at more than 2500 RPM. I only rodded out the tubes and cleaned the end caps and it cured the overheating. The tubes and end caps were gunged up.

 

[sailorman]

Is this common pratice with Beta Engines?
To be honest, apart from annual oil and filter change, I don't touch my Yanmar.
Seems to be all that's required.
If it ain't broke, don't fix it.

i find the same with my Nanni 4150.
i changed the H.E "O" rings last year & 700hrs & the stack was clear as a bell
when i bought & fitted my Nanni i was told that they are better marinised than Beta. it does seem that way

 

[bob26]

Is this common pratice with Beta Engines?
To be honest, apart from annual oil and filter change, I don't touch my Yanmar.
Seems to be all that's required.
If it ain't broke, don't fix it.

I believe Yanmar owners are deprived of these pleasures as they don't normally have heat exchangers...but they shouldn't be too smug with those leaky raw water pumps that rust the oil pipes when they leak...

 

[Tranona]

i find the same with my Nanni 4150.
i changed the H.E "O" rings last year & 700hrs & the stack was clear as a bell
when i bought & fitted my Nanni i was told that they are better marinised than Beta. it does seem that way

Interesting observation. Have just installed a Nanni and one of the deciding factors (apart from the fact it is blue rather than red) was the heat exchanger. This problem comes up regularly with Beta engines here, togerther with short anode life. Perhaps the frequency of the problem is because of the greater numbers of Betas in service. The other main factor for me was the heavier flywheel of the model I have (14) which means a lower tickover which helps low speed maneouvering.

Have not run it yet as only just finished connecting everything up - but it went straight into the same place as the Yanmar 1GM with only mods to raise the beds, swapping the exhaust to the other side and a larger water intake. Have been impressed so far with how well everything went together.

 

[sailorman]

Interesting observation. Have just installed a Nanni and one of the deciding factors (apart from the fact it is blue rather than red) was the heat exchanger. This problem comes up regularly with Beta engines here, togerther with short anode life. Perhaps the frequency of the problem is because of the greater numbers of Betas in service. The other main factor for me was the heavier flywheel of the model I have (14) which means a lower tickover which helps low speed maneouvering.

Have not run it yet as only just finished connecting everything up - but it went straight into the same place as the Yanmar 1GM with only mods to raise the beds, swapping the exhaust to the other side and a larger water intake. Have been impressed so far with how well everything went together.

i re-engined + new shaft,rope cutter + sea cocks + a/f & polish relaunched engine running in 7 days .
the engine relpaced a perkie 4108 i had to coarsen the pitch on the MaxProp to get the revs down below 3000 so the Nanni 4150 has more torque the perkie ran @ 2900 max rpm loaded.
the transom came up 50m/m due to the lighter engine

 

[PembrokeshirePromise]

I seem to suffer this problem - I do remove mine each year.
The actual copper heat exchanger is normally fairly easy to remove once you've got the end caps off.
These do seem to stick to the aluminium housing despite the O rings and a variety of duralec type compounds I've tried.
I remove mine by putting a bar across the end with near the exhaust - with a longer bolt into the copper central stack and wind it out with a spanner - pulling the end cap with it.

Similar approach with the other end (and some heat and not so gentle tapping) - though I have a threaded bar that I can pass through the end cap (once the copper tube has been removed) and again with a bar and appropriately place bolts can wind it off

Not sure I've described it very well - if someone can explain how to prevent it happening I'd be delighted!

 

[EuanMcKenzie]

try boiling it?

Don't know if you can remove the whole heat exchanger easily?

i did that with my Volvo Heat ex and took it home and boiled in a tub to remove the crud and salt. then it came apart.

Had to rebuild with new seals after but it sorted it properly without damaging the matrix.

i know you should n't have to but the thought may help.

 

[alahol2]

I seem to suffer this problem - I do remove mine each year.
The actual copper heat exchanger is normally fairly easy to remove once you've got the end caps off.
These do seem to stick to the aluminium housing despite the O rings and a variety of duralec type compounds I've tried.

I must admit I've never had a problem removing the end caps. I only ever put a thin smear of silicone grease on them. They should only really be seated onto the 'o' ring and be an interference fit into the body of the exchanger. I would run round the end caps with a bit of emery cloth to make sure they are clean and slide in and out of the housing without problem.
The end bolts should only be tight enough to compress the 'o' rings.

 

[PembrokeshirePromise]

I must admit I've never had a problem removing the end caps. I only ever put a thin smear of silicone grease on them. They should only really be seated onto the 'o' ring and be an interference fit into the body of the exchanger. I would run round the end caps with a bit of emery cloth to make sure they are clean and slide in and out of the housing without problem.
The end bolts should only be tight enough to compress the 'o' rings.

Thats what I tried the first year - but it still stuck. The end caps are an interference fit once free - the problem seems to be slight galvanic corrosion that sticks the end caps (bronze?) to the aluminium housing. I don't know if this is caused by slight initial weaping past the O rings that then "bridges" the rubber or what.

As far as I can tell the pencil anode is in there and doing what it should

I've rubbed back with emery paper this year - so we'll see what happens. Its annoying - because its the only bit of the engine I have any problems with.

 

[Thistle]

Have you tried talking to Beta Marine? Always very helpful whenever I've talked to them.

Many thanks for this and all the other suggestions on the thread. I spoke to Beta this afternoon and, as predicted, they were very helpful.

They suggested, once the end caps were off and the 'O' rings removed, gently scraping round the edge of the stack with a fine blade to remove some of the crud, being careful not to scratch the aluminium housing. Then gentle taps to loosen the stack, followed by working it back and forth until it is free. DO NOT hit it hard as that may buckle the stack.

When clean, replace it carefully with the slotted end of the stack towards the gearbox. Be careful to align the slot so that it mates with the end cap. (Note: this is not mentioned in the manual but failure to do it can, apparently, damage the stack.) Finally, tighten the end caps evenly, taking care not to overtighten.

Guess what I'm doing this weekend!

 

[PembrokeshirePromise]

Many thanks for this and all the other suggestions on the thread. I spoke to Beta this afternoon and, as predicted, they were very helpful.

They suggested, once the end caps were off and the 'O' rings removed, gently scraping round the edge of the stack with a fine blade to remove some of the crud, being careful not to scratch the aluminium housing. Then gentle taps to loosen the stack, followed by working it back and forth until it is free. DO NOT hit it hard as that may buckle the stack.

When clean, replace it carefully with the slotted end of the stack towards the gearbox. Be careful to align the slot so that it mates with the end cap. (Note: this is not mentioned in the manual but failure to do it can, apparently, damage the stack.) Finally, tighten the end caps evenly, taking care not to overtighten.

Guess what I'm doing this weekend!

Good luck - hope it goes well. My problem has never been getting the stack out - its been getting the end caps off. Mine took a bit more than scraping and a gentle wiggle !

 

[sailorman]

Thats what I tried the first year - but it still stuck. The end caps are an interference fit once free - the problem seems to be slight galvanic corrosion that sticks the end caps (bronze?) to the aluminium housing. I don't know if this is caused by slight initial weaping past the O rings that then "bridges" the rubber or what.

As far as I can tell the pencil anode is in there and doing what it should

I've rubbed back with emery paper this year - so we'll see what happens. Its annoying - because its the only bit of the engine I have any problems with.

the end caps should not come into direct contact with the h/e housing.
the "O" ring should separate the two or Galvanic action will occur

 

[alahol2]

the end caps should not come into direct contact with the h/e housing.
the "O" ring should separate the two or Galvanic action will occur

It would be almost impossible to prevent the end caps from touching the housing, they actually slide into the housing. The 'o' rings sit in the chamfer of the cooling stack and are compressed by the end edge of the end caps. This pushes the 'o' rings out and onto the housing, a sort of three surface seal.