beta heat exchanger stack - possible cleaning bodge?

[Burnham Bob]

Thanks for advice on the previous post about cleaning the heat exchanger stack but having now tried to get at it there is no chance whatsoever of removing the back cap. I can't even get at the hoses to loosen them off to allow free movement of the cap. The engine must have been shoehorned into place.

How about just removing the front cap, leaving the rear one in place and rodding through the holes?

I think a forumite advised that previously anyway. It looks like any **** that gets disturbed would simply wash into the exhaust. I'll replace the O ring on the front cap but just leave everything at the back of the engine undistubed. Presumably the rear cap will just stay in place?

Or am i just being an optimist with a natural inclination towards bodged solutions?

 

[Thistle]

You don't say which Beta you have. In some (or all?) the engine anode is screwed into the rear cap. On my engine (Beta 10) it was crud from the anode that was blocking that end of things; the front end was much clearer with just a few bits and pieces (eg polystyrene beads) that had got through the system that far.

I know it doesn't help you much, but from what I've seen, I'd be prepared to leave the front cap on but would want to get the back one off. That said, I reckon your suggestion would be better than nothing.

 

[Haven't-a-Clue]

Thanks for advice on the previous post about cleaning the heat exchanger stack but having now tried to get at it there is no chance whatsoever of removing the back cap. I can't even get at the hoses to loosen them off to allow free movement of the cap. The engine must have been shoehorned into place.

How about just removing the front cap, leaving the rear one in place and rodding through the holes?

I think a forumite advised that previously anyway. It looks like any **** that gets disturbed would simply wash into the exhaust. I'll replace the O ring on the front cap but just leave everything at the back of the engine undistubed. Presumably the rear cap will just stay in place?

Or am i just being an optimist with a natural inclination towards bodged solutions?

Having just done this job myself partly as a direct result of your previous thread, I found that it was the front cap that wouldn't come off, ho hum. However the rear cap came off fairly easily, so I was able to see that the partial blockage was caused by the disintegrating anode itself, so be aware that aconsiderable amount off "rodding" may be required, pipe cleaners don't work !! Also due to the direction of flow, as I recall, cool in through the bottom and out through the top, rodding in one direction may just end up with a pile of shagged anode bits just waiting to block up the holes again. I was fortunate enough NOT to have a hammer on board, so was obliged to re-insert the cap holding bolt into the non-moving cap and tap it in with a ratchet handle to get the exchanger itself onstuck..........gawd knows what damage I could have done with a hammer, so tap it gentlyand it will eventually free itself. Please pm me with a landline number and I'll happily explain ad infinitum.

 

[dovekie]

I've just been in touch with Beta myself, about this on a Beta 38. They say that the exchanger stack can be withdrawn either way - forwards or backwards, i.e. by removing either cap. On my installation I have the choice of removing an exhaust dry riser in an inaccessible position at the gearbox end of the engine, or removing the alternator and removing the stack the other way. Whether in practise that means the stack will remove easily I don't yet know.

 

[Thistle]

Yes ......... but aren't the caps held on by bolts which go through the caps and into the stack? And if you only remove one cap, the stack should come out easily but how do you replace the O-ring at the other end?

 

[Piers]

One of my tasks before the season starts is to de-scale the heat exchanger on each engine, but not just the heat exchanger but the whole raw water system. Therefore, I'm going to copy what someone else had done.

Make sure your sea cock works, or to be absolutely safe, do it when the boat is out of the water!

Disconnect the hose from the outlet of the raw water pump and link it to a long piece of hosing to the outlet of a bilge pump which you place in a large bucket. This is where the de-scaling will start (and you don't need to de-scale the water pump).

Then, disconnect the hose which dumps the raw water into the hot exhaust system, and connect it to another length of hose back to the bucket. You now have a closed loop routing via the bucket.

Fill the bucket with the correct dilution of Rydlyme and start the bilge pump. If the water level in the bucket goes down too far, and more Rydlyme. Keep flushing for a few hours or until the liquid stops fizzing at which point de-scaling will be complete.

Top job, with no mechanical removals at all!

Rydlyme

 

[Haven't-a-Clue]

O rings

Yes ......... but aren't the caps held on by bolts which go through the caps and into the stack? And if you only remove one cap, the stack should come out easily but how do you replace the O-ring at the other end?

Well as far as I went, the front cap was still stuck fast and isn't leaking, so I didn't bother............still water tight now. Don't worry about, I guess. Oh, one other thing, descale the hoses as best you can before replacing as otherwise (like I did!) you end up with a small leak which seems to be coming from the O ring you've just replaced, but isn't!

 

[onenyala]

I have exactly the same problem. I did the following :
Remove accessible cap ie the one ajacent to the alternator.
Remove the anode stud.
Remove the impeller cover and impeller.
Using a piece of bike mud guard stay which is a neat sliding fit in the stack cooling tubes rod through each tube making sure the rod is long enough to go the full length of the tube and a bit.
Using the same type of rod I made a 'rake' with an upturn high enough to be able to get it through the anode stud aperture rake and worry out the crud from the inaccessible bell housing.
In addition I used my inflatable pump to blast air in through the anode stud aperture and through the pipe back to the salt water pump to ensure the pipe was clear.
It seems to be the only solution short of taking the engine out !

 

[Burnham Bob]

thanks for the advice. i actually have a really good flow of cooling water out of the exhaust, so this is not to cure overheating, it's just that the manual says it ought to be done.

as to the anode bits, don't they waste away as the sacrifical anode ought to - even if they've dropped off the bolt? So in time if there are some, they'll disappear.

and can anyone tell me how the O rings actually attach? do they stretch over and into a groove or are they just resting on a reces at the end of the stack ready to be compressed?

I'm beginning to think that if I take the front cap off and remove the stack forwards, then I might just have enough movement on the rear cap to 'feel' the O ring into place and then 'feel' the slo on the cap into place to position the stack properly.

 

[Haven't-a-Clue]

The O rings fit into a recess when the stack is fully seated, but............you gotta be real carefull putting the cap back on if you can't actually see directly, as in my case. I must have put it in and taken it out about half a dozen times, worrying like hell that it wasn't correctly seated. I eventually overcame my (just!) sub-clinical paranoia and threaded the bolt in very carefully and it seemed to go OK, with no leaks.........so far. Nurse, the tablets, please.

 

[LittleSister]

as to the anode bits, don't they waste away as the sacrifical anode ought to - even if they've dropped off the bolt? So in time if there are some, they'll disappear.

As I understand it the anode will only waste while it is part of a circuit. Once it falls out of its bolt, it is no longer part of a circuit. Something else will now be wasting away instead!!!

 

[Haven't-a-Clue]

As I understand it the anode will only waste while it is part of a circuit. Once it falls out of its bolt, it is no longer part of a circuit. Something else will now be wasting away instead!!!

That's how I understand it too...........I guess we await correction. Incidentally, the new anode I was supplied with seems to have a slightly tapered thread, as opposed to the parallel thread on the original, so carefull with that spanner when tightening up as well.........or could just be my end cap, I 'spose, but the Beta guy who fitted it for me ('cos I didn't want to break it by overtightening, preferring to let him break it instead) said that's how they come now.

 

[PetiteFleur]

Thanks for advice on the previous post about cleaning the heat exchanger stack but having now tried to get at it there is no chance whatsoever of removing the back cap. I can't even get at the hoses to loosen them off to allow free movement of the cap. The engine must have been shoehorned into place.

How about just removing the front cap, leaving the rear one in place and rodding through the holes?

I think a forumite advised that previously anyway. It looks like any **** that gets disturbed would simply wash into the exhaust. I'll replace the O ring on the front cap but just leave everything at the back of the engine undistubed. Presumably the rear cap will just stay in place?

Or am i just being an optimist with a natural inclination towards bodged solutions?

I cleaned out my Beta 25 at the end of last year as I had an overheated problem when running at over 2500 RPM. I can easily get at both ends so removed the hoses and then the end caps - had to lightly tap the caps to get them to move. I decided not to remove the inner tube assy as it appeared to be stuck. All the crud was at the rear anode end and included bits of impellor. I rodded out each tube with a piece of wire, cleaned the end caps, renewed the anode and refitted the endcaps without renewing the 'O' rings. Ran the engine at 3300RPM for ½hr so cured the overheating problem. I now keep a 2.5mm Ø rod in my toolbox.

 

[sailorman]

I cleaned out my Beta 25 at the end of last year as I had an overheated problem when running at over 2500 RPM. I can easily get at both ends so removed the hoses and then the end caps - had to lightly tap the caps to get them to move. I decided not to remove the inner tube assy as it appeared to be stuck. All the crud was at the rear anode end and included bits of impellor. I rodded out each tube with a piece of wire, cleaned the end caps, renewed the anode and refitted the endcaps without renewing the 'O' rings. Ran the engine at 3300RPM for ½hr so cured the overheating problem. I now keep a 2.5mm Ø rod in my toolbox.

Nanni recommend replacing the O rings every 400 hrs.
dont over tighten as they are supposed to keep the end cap from touching the main body

 

[Pye_End]

As I understand it the anode will only waste while it is part of a circuit. Once it falls out of its bolt, it is no longer part of a circuit. Something else will now be wasting away instead!!!

Presumably, if they are in contact with the casing, or the stack, or the end cap - and they do seem to weld themselves to these bits - then they will still be part of the circuit and therefore still an anode.

 

[stevebirch2002]

Straight from the Beta Expert (Adrian)

Guide to cleaning Beta Marine tube stack



1 ) Drain off coolant into a bucket

2) Unscrew the 2 end cap retaining bolts( one each end of the tube stack)

3) Remove the o rings

4) Clean the edge of the tube stack tunnel ( but not too much as to cut into the aluminium )

5) Flush it out with WD40 or similar if required

6) ease the tube stack backwards and forwards and slide it out

7) Clean the tube stack inside and out side the tubes



Refitting

8) Make sure the tube stack is the correct way around ie align the tube stack slot with the slot in the end cap

9)fit new o rings

10) fit end caps and tighten both end caps evenly by hand making sure the o rings are evenly loaded and keeping the tube stack central and aligned with the end cap

11) tighten the end cap bolts , but do not over tighten

12)refill the engine with anti freeze solution and run engine checking for leaks


S

 

[Seven Spades]

I don't understand this how can an anode be inside the engine? Am I misunderstanding something, but I have a shaft anode and another on the outside of the hull is there a third I don't know about? I have a Beta 38.

 

[Burnham Bob]

there is an engine anode - it protects the bits of your engine that will be attacked by elctrolytic action the same way the shaft and hull anode proetc the other metal bits.

in the beta 14 (my engine) its in the heat exchanger housing - just a simple bolt that holds a small zinc rod.

inspection and changing is a doddle. unscrew the bolt (your manual will show you where it is) and look. If there's no zinc - just the brass bolt - you need a new one.

cheap non-beta anodes are on e-bay. just screw a new one back in. they also do new replacements which just screw into the brass bolt when the old one has eroded

 

[VicS]

and this is the picture from the Beta manual showing the anode.

 

[doug748]

.....

Or am i just being an optimist with a natural inclination towards bodged solutions?

I would not say that, but in the final analysis you really need to get the back cover off if at all possible.
On most set ups it is just possible working backwards, in the dark, at full arm extension. The photo above shows the problem nicely. Remove the hose and clip first to give yourself a chance.
It does get easier.