I have overheating problems with my beta 10 . After overheating some gunk appeared in the heat exchanger where you top up the coolant! When idling it will shift 6 litres of seawater/min. but when revved up this does not increase much if at all I have checked the impeller, it's ok I have replaced the thermostat (which was removed to see if that would help), it's ok The sea**** and piping is clear I removed the heat exchanger and cleaned it, it's ok. There's a separator bar across the back cap of the heat exchanger which does not have any kind of seal fitted to it, is that how it should be ?
The raw water flow should increase as the engine revs up. If it doesn't, look for a partial blockage. This may be in the raw water pump outlet fitting or the exhaust elbow water injection fitting.
The thermostat must be fitted or the engine will overheat.
What temperature is the engine running at? At what RPM? can you get full RPM in gear?
The seperator on the aft end cap for the heat exchanger on the older design has no seal. The seperator just fits into the slot on the tube stack.
The newer design does have a seal there but no slot for lining up the tube stack, just some alignment marks.
Hi Stanley , thanks for your very helpful reply. I bought the engine used so dont know the history I will check the exhaust elbow, (never thought of that) Stat has been refitted. Sorry but I have no temp. guage or rev counter. Would a makeshift seperater seal on the aft cap help at all ? The exhaust makes a horrible whooshing sound The sea**** is only 1/2" but when I took off the raw water feed hose and placed it in a bucket of water there was no improvement Could the raw water pump be done? there is some wear on the face plate where the impellor is being squeezed by the cam
It is very possible that your raw water pump is down on flow. The wear on the cover plate will be mirrored on the back of the pump body reducing efficiency but first you must ascertain why the flow doesn't increase when the revs increase.
A makeshift seal on the divider will cause many more problems that it will potentially solve. A 3/4" full flow intake valve and fitting will help you.
You never said what year the engine is, only that it is used. As far as exhaust noise is concerned, the design of the exhaust system can dramatically change its sound. Again, please provide full information or I cant help. How is the exhaust laid out? What waterlock muffler are you using?
Hi Stanley The exhaust consists of a vetus 4 litre water trap 'type lp50' fitted below the manifold with a 50 mm hose from there to the transom, looped high before exit
Thanks very much for help Stanley, I think I have found the main cause of the problem. I removed the exhaust where it was terminated at the transom, it was joined to a 38 mm right angle outlet pipe. the reduction having caused debris to collect there which prevented the water escaping when revved up. I will need to replace the exit bend with a 50mm one - I just hope no damage was done
