beta 35 quandry

[causeway]

I had an issue with my impeller and lost 4 of the blades.

New impeller is in and it is pumping water but I'm worried its not pumping enough.

How can I tell?

I think I got all the blades off the old one but I can't be sure!

The amount of water coming out seems a bit 'random' and it seems to be quite steamy.

Water strainer has been done.

Any help appreciated!

 

[ianc1200]

I have removed the old impeller, retrieved the fins in the hose, but the fins against the impeller to try to "rebuild" the complete impeller, found I was missing a bit & rechecked the hose to find the other missing bit.

I used to have an old BMC 1.5 and the perceived wisdom was it was spate out of the exhaust (it was raw water cooled) but on the Nanni the engineer was most insistent I made sure all the bits were located to ensure not floating around the system.

 

[causeway]

Yeah, from what I've read, if a fin is stuck in the exchanger or anywhere in the system could be an issue. I guess I'll have to take out the exchanger? At least my access to the engine isn't terrible.

 

[doug748]

The broken bits normally lodge in the back of the heat exchanger, by the anode, on the smaller engines. Your machine may be similar.

I would avoid Johnson impellers at all cost and use Jabsco replacements.

 

[PetiteFleur]

When I had an impellor break up, I had overheating problems so stripped the heat exchanger and found lots of impellor bits in the rear part near the anode. Also cleaned out all the tubes and overheating cured. On a Beta 25.

 

[causeway]

Did you just have to take out the exchanger from the back? How did you check the hoses?

This is all good info thanks everyone.

How can I check the top end of the heat exchanger? Just pull it and look up?

 

[LittleSister]

New impeller is in and it is pumping water but I'm worried its not pumping enough.

How can I tell?

The owner's manual for my smaller Beta states how much water it pumps (or should) at tickover or certain low revs (can't remember which). Doesn't yours? Easy enough to measure if it does.

p.s. If the manual doesn't tell you ring and ask Beta. They're very helpful.

 

[causeway]

Well, that answers that question! 12L per minute @ 1500rpm

I don't think mine is pushing that.

Oh dear.

Hopefully this will be useful to someone in the future.

 

[LittleSister]

View attachment 41582

Well, that answers that question! 12L per minute @ 1500rpm

I don't think mine is pushing that.

Oh dear.

Hopefully this will be useful to someone in the future.

May well be easier to take the water inlet hose off its seacock and measure the water sucked in by the the pump (from a bowl, bucket or whatever), rather than to try to collect & measure what is coming out the exhaust.

 

[causeway]

That's a great idea, thanks! Maybe I better just go the whole hog for my own peace of mind anyway though.

 

[rob2]

I just wondered, has anyone successfully reverse flushed the line to get all the bits out? That would at least get a workable system quite quickly, although there is much to be said for taking the incident as a trigger to clean out the heat exchanger tubes...

Rob.

 

[causeway]

Seems like a simple enough plan. Tube off the back, impeller out, flush.

Also handy to know!

 

[Old Rhodie]

Much to my astonishment - some of the blades in mine actually were in the supply pipe between intake hull fitting/filter and the pump. The only place I didn't look !
This caused low flow at medium to high revs.
ken

 

[john_q]

After many years of picking impeller bits out of my heat exchanger, 2 years ago, I fitted a Vetus water strainer between the sea water pump and the heat exchanger. This catchs any blade tips that break off and has saved many hours of taking the dismatling the engine to get at the heat exchanger to clean it

 

[LittleSister]

After many years of picking impeller bits out of my heat exchanger, 2 years ago, I fitted a Vetus water strainer between the sea water pump and the heat exchanger. This catchs any blade tips that break off and has saved many hours of taking the dismatling the engine to get at the heat exchanger to clean it

After years of never having had to pick bits out of the heat exchanger, I continue to change the impellor annually!

 

[causeway]

I put these in another thread but probably best to share them here again.

 

[Jim@sea]

My last boat (15 years old) had low engine hours when I bought it. It had been serviced 80 hours previously but that was 5 years ago. On the service schedule the impeller was described as "serviceable" and was not replaced.
The pump was in a virtually inaccessible place, you could just reach the bolts which held the plate on but there was no room hold a pair of pliers to try and pull the impeller out.
I had to get a marine engineer to strip the side of the engine and take the pump out.
(and once I had watched him do it I could do it myself)
When the impeller was taken out it had started disintegrating 3 of the fins were missing and all the others were splitting at the base.
I believe that when the engine was serviced, if they were on a fixed price they could not be bothered to change the impeller as it was a 3 hour job, consequently it would not surprise me if the impeller was the original one being 15 years old
I always fit a new one at the start of the season and keep the one I took out as a spare.