Beta heat exchanger

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13.5hp

Rear domed end cap (the one with intlet, outlet and anode) won't come off. (Bolt is out but won't shift, other end dome came off no bother).

Any and all ideas, as always, gratefully received.

- W
 
webcraft said:
.

13.5hp

Rear domed end cap (the one with intlet, outlet and anode) won't come off. (Bolt is out but won't shift, other end dome came off no bother).

Any and all ideas, as always, gratefully received.

- W
Click to expand...

I recall similar problems. Assume you've removed the cockpit floor hatch for better access and taken off the hose? I think a bit of brute force came in handy when I did it... possibly with the use of a lever in the hose outlet to impart a rotation. It was a while ago though and the details are a bit hazy.
 
Can you get the cooling stack out? It should just slide forward put the bolt in and pull, if so, tap the other end cap with a piece of broom handle from the 'inside'. If not I would be tapping round the outside with a block of wood, probably just a bit of dried salt jamming it.
 
macd said:
Not sure of the set-up on the 13.5 (I had a 28). But some people removed only one end cap. Is it possible to rig up a puller (8mm studding?) and start to draw the tube stack out. Once moving it's usually quite easy.
Click to expand...

Hi
I have the Beta 20 on my Vindo. I slacken the alternator, remove belt and swing alternator out of way to get at the front dome of the exchanger. If it you can't get the rear dome off, I would give the exchanger a tap at the front with a heavy hammer and a block of wood. Your rear dome is probably just stuck with salt deposits.
 
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As usual a great set of repsonses in the short time I have been up the pub having a couple of pints of Hurricane Jack.

Will try all these ideas, and also came up with an other one half way through my second pint. I have some nylon rod - I could cut an appropriate length of this and pass it through one of the tubes of the exchanger until it was against the rear end cap then give it a tap.

I'll report back afterwards.

- W
 
Once the M8 bolt is removed there is nothing else there holding it in place so as others here have said a few light taps with a hammer should help to remove it. It is designed to have a very flush edge against the aluminium body so that a good seal can be made between the header, stack and body using an O Ring. Occasionally over time this can become a bit stuck as many engine components often do.

It is best to avoid impacting the tube stack as, although these are built to be strong, they are constructed from several small components with soldered joints so they are more likely to be damaged than the header dome.
 
My Beta 13.5 rear h/e cap had to be 'gently persuaded' first time I took it off. I removed the hose first and firmly tapped the sides of the cap and the nozzle and it came free.

I wouldn't want to be hitting the stack. As mentioned (and what I didn't realise at that time), the stack can be removed from the front with the rear cap in place (but bolt removed). Once the stack is out you can presumably easily knock the rear cap out from inside.
 
Either give it a few whacks with a plastic or rubber mallet or gently tap a wedge/chisel into the joint. It will just be salt and/ or gasket compound holding it on.
 
interested in the post that says the stack can be removed from the front with the rear cap in place. My beta is installed in a very tight space and getting to the back bolt is a mtter of feel and I don't fancy trying to relocate the end cap by feel whiklst not dropping the O ring.

If i could just pull the stack out. clean it then replace it - making sure the 'groove' is horizontal - life would be a lot easier.
 
Burnham Bob said:
interested in the post that says the stack can be removed from the front with the rear cap in place. My beta is installed in a very tight space and getting to the back bolt is a mtter of feel and I don't fancy trying to relocate the end cap by feel whiklst not dropping the O ring.

If i could just pull the stack out. clean it then replace it - making sure the 'groove' is horizontal - life would be a lot easier.
Click to expand...

I've got neither the engine nor the manual in front of me, but if I remember rightly the stack just sits in the middle and the bolts through each end cap just bolt into a threaded hole in either end of the stack clamping the two end caps (sitting on O rings) against the housing body.

I've not done it myself, but I think if you take out the rear bolt, take out the front bolt, take off the front cap, remove the front O ring, rescrew the front bolt into the stack, you should now be able to pull the stack out using the bolt. If the stack is stuck in with scale etc., you might need to rig up something (front cap with something to hold it off the housing body?) to use as a puller.

As I say, this is all from memory, so hope maybe someone else can confirm or otherwise, or you should check in the manual. So long as you don't use excessive force, you shouldn't do any damage even if I'm wrong.
 
On my 13.5 I don't think I can get the stack out at the front because the alternator gets in the way. But if there was more space to swing the alternator to the side then it would probably come straight out.
 
Burnham Bob said:
interested in the post that says the stack can be removed from the front with the rear cap in place. My beta is installed in a very tight space and getting to the back bolt is a mtter of feel and I don't fancy trying to relocate the end cap by feel whiklst not dropping the O ring.

If i could just pull the stack out. clean it then replace it - making sure the 'groove' is horizontal - life would be a lot easier.
Click to expand...


It is as LittleSister has said. The stack sits in the middle and the the domes on the end are clamped onto it, squashing the O rings. ***

Removing just the front one, and the stack, might prove tricky and the only thing holding the rear on will be faith and encrusted salt. It could work but it is generally good policy to inspect the O ring and end cap. I also like to smear them with waterproof grease. It is a pain working back to front, in the dark, but once you see how matters are arranged it makes it easier. A bloke once posted a photo of a severely neglected Beta heat exchanger and the whole of the rear had been eaten away, a grisly sight.

I can confirm that on the 20hp unit the matrix, in theory, can be taken out from the front or rear. However if you have a high rise exhaust that stuffs up the rear tactic and the alternator has to be moved when pulling the thing out from the front.

*** The design has been changed on the newest engines.
 
Having just done this job on our BZ482 I can confirm that everything will be stuck together with corrosion/deposits necessitating a good smacking/levering/heating/spraying with penetrating fluid ect.In theory the the tube stack can be removed from the front after undoing the alternator bolts and swinging it out the way but you still have to undo the rear cap bolt to let it slide out.In practice it won't cause it'll be stuck with corrosion.We had smack our tube stack out with a wooden drift.Best to look carefully at the wee piece of hose from the thermostate housing to heat exchanger too.Ours was cracked on the underside so not visible untill the jubilee clips loosened and hose rotated.Its seven eights inch ID by the way and you might need a new thermostate housing gasket..Once all cleaned up and greased it slides in easily but only from the front on ours due to highrise exhaust elbow
 
The tube stack can be removed from one end whilst the cap is still in place on the other end (obviously the bolt will need to be removed first) but when removing the headers on any heat exchanger which have O Ring seals we recommend replacing the O Rings as a matter of course. Once they are all bolted together the seals are compressed to form a tight seal (no need for any gasketing or sealing agents) but after a few months under compression there is a risk that they won't "bounce back" sufficiently to provide a seal. You should get away with this on newer engines but seal will perish eventually.

If you can remove both end caps, then this is the preferred method, if not then remove the stack but check for leaks on the "fixed" end when re-assembled. A good place to get these O Rings is ASAP Supplies, the same universal O Ring is used on all of the Kubota/Beta Marine engines up until they changed their heat exchanged Mani-Coolers around 2 years ago.
 
webcraft said:
.

13.5hp

Rear domed end cap (the one with intlet, outlet and anode) won't come off. (Bolt is out but won't shift, other end dome came off no bother).

Any and all ideas, as always, gratefully received.

- W
Click to expand...

My Vega had an overheating problem at tickover but was ok underway. The water from the exhaust seemed less than usual. The impellor was ok so I removed the heater tube stack...........big mistake!

The stack was pretty gunged up so that was duly cleaned, the problem was when I put it all back together. I just could not get a seal on the aft end cap. Water was pouring out no matter what I did regarding seal fitting and end cap tightening sequence .I have done this job numerous times before with no trouble.

On closer inspection the rear end of the heat exchange tank was seriously pitted and eaten away. I was never going to get a waterproof seal as there was nothing left to seal to.

The problem was compounded by not only the difficult access to the rear end of the heat exchange tank on a Vega resulting in alternating between hanging upside down leaning into the engine compartment or crouching in there and peering up to the left whilst trying to work mainly with my left hand. In addition to being stuck up the top end of Loch Sunart a long way from workshop facilities and or chandlery.

I contacted Betamarine, after explaining the problem to the tech support guy he asked me the year of manufacture of the
engine. I told him 2006, he immediately stopped trying to tell me how to fit the O ring seal and said I had 2 options. First option buy some epoxy and rebuild the area that had been eaten away or replace the tank with the new improved version. He was keen to stress that as it was a design fault ( not his words ) he could sell me one at a special price. As the required clearance above the tank to clear the studs was to much for a Vega the engine would require removal I opted for the first option.

I eventually succeeded with the epoxy. The reason for this monologue is to warn you if your engine is of a similar vintage do not remove the heat exchange stack. Remove the end caps, a large Phillips screwdriver in the bolt hole and worked side to side will break the encrusted seal, and clear the tubes insitu with a suitable sized screwdriver or metal rod. New O rings and feel allround the caps to ensure the seal is located as you tighten.
 
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