This year whilst winterising the engine I noticed the engine struggled to pull up the antifreeze mix from a 5litre water bottle. I made a temporary seal around the neck of the bottle which made some difference.
I have spoken with Bukh in Poole and they were very helpful suggesting that the pump may need an overhaul as they would expect the coolant to be pulled through fairly effortlessly.
My previous posts on the forum demonstrate my concern that we have been overheating with more steam than normal. I know Bukh's steam but I think it has been increasing.
Any thoughts re spending money on a revamp or a buy new?
I believe it will cost around £150-180 for servicing existing and for similar money get new one.
I have had the gas poker out and cleaned area, manifold off and no blockages including the water pipe from the thermostat to exhaust. So zeroing in on pump as it was sluggish.
Your thoughts appreciated.
Results 1 to 8 of 8
16-02-11, 18:49 #1
Bukh DV20ME new water pump or revamp
Last edited by benw; 16-02-11 at 18:52.
16-02-11, 19:50 #2
You dont say if the impeller was newish or not.
That's normally the first thing to replace.
( dont understand the need for the seal around the neck of the antifreeze bottle ??? I'd have though that would have been counter productive)
Pumps can wear... inspect! .... not only around the periphery but in the ends as well.
The cam plate may be replaceable.Sea Wych Owners Association: www.Seawych.org
16-02-11, 19:57 #3
Thanks for this, the impellor was new last year.
I removed the raw water pipe from the seacock and placed it in the water bottle which was on the cabin sole. Having flushed the engine with 10 litres freshwater I then used a third 5litre bottle with the measured antifreeze.
As I put the pipe in each bottle it seemed to take an age to start drawing up the water, the final bottle took the longest to start drawing.
I must admit that I didnt then inspect the impellor as the antifreeze had gone in and the boat was then craned out.
Will be back on board next week so hence my growing desire for some options to explore whilst off the water.
16-02-11, 20:02 #4
Did you check the elbow joint either side of the pump? I found a small blockage in my dv20 once which was the source of my water flow problems.
16-02-11, 20:11 #5
Good point, Bukh suggested this as they have found impellor blade debris there too. Will be one of the checks I make next week when back on the boat. Haven't been on board since lifted out Nov.
17-02-11, 07:27 #6Registered User
Location : Woodbridge. Suffolk
- Join Date
- Sep 2001
I have a DVME20 in my 30 year old Konsort. Noticed this last year that I was getting more steam than usual and the temperature was higher than normal. Checks revealed no apparent blockage and running without thermostat improved matters slightly. Advised by BUKH (great guys!) to remove cylinder head and fill waterways with kettle descaler. Worked a treat and now runs at correct temperature. Quite a lot of carbon type deposit in waterways..this comes about as a result of initial start exhaust gases coming back into head waterways by way of exhaust which initially has no back pressure from water pump..(talk to BUKH at Poole)
17-02-11, 07:44 #7
When my water pumps have failed to prime it has usually been because the face plate, and presumably the body back, have worn. Thus there is clearance between the impeller and the face plate. On some plates it is possible to just turn it round and use the other side. If this is not possible, due to bolt position or stamped letters on the outer side, then it is possible to grind the inner face flat again using wet and dry papers on a flat surface.
Ultimately of course this will do no good as the inner face cannot be treated in the same way. If you were really confident about your ability to grind flat you could give the pump body the same treatment, taking a small amount off the front face to restore the inner depth to original.
While doing all this it would be a good idea to replace the shaft seals, as failure of these leads to many problems on Bukh engines.Answers to some technical queries at http://coxengineering.sharepoint.com
17-02-11, 10:57 #8
Thanks for theatre posts. incidentally I did replace the front plate last year as the existing one had been worn and reversed already by the previous owner.
When I changed the impellor last time the rod that engages with the impeller centre came out with it as I pulled the impeller. Once I notice this was happening I simply pushed the rod back into position without any further thought. Have I missed something big here?
Regarding the taking off of the cylinder head is this an easy thing for a movie to attempt?
This is my first inboard and whilst for some winterising may be an easy set of tasks for most it ranks highly in my engineering career/experience to date!
When I spoke with bush they advised not to run any descaler in the system because of sensitive seals throughout the engine?
I am delighted to have your responses particularly having been ticked off for posting this on the ECF forum too.