Re: [Amel Yacht Owners] Volvos.......


karkauai
 

Hi Ian,
Do you have an AutoProp?  My understanding is that they are ver persnickety about growth.  I'd take PenAzen out for another trial and if all is OK, I'd probably opt for "if it ain't broke, don't fix it."

I understand there is a wire mesh filter in the tank at the outflow.  I don't know how to get to it, but if it is clogged you may have a fuel starvation there, which could be intermittent as fuel sloshes around.  Do you have a pressure gauge in the supply line?  Kristy has a dual racor setup with a gauge.  If there is a blockage in supply line it should read negative pressure.

Not a mechanic, but that's the first two things that come to mind.

Kent Robertson
S/V Kristy
SM 243
Heading for St Michaels, MD for the Summer.

On Apr 26, 2018, at 12:13 PM, Ian & Judy ianjudyjenkins@... [amelyachtowners] <amelyachtowners@...> wrote:

 

Hi All,


I thought this subject had been reviewed so many times that there was nothing else to know. However.....


Last year our 78hp Volvo was partially rebuilt by the Volvo agent in Hyeres. Not a happy experience, but we did end up with an engine performing as it should. With a clean bottom and prop  the rev counter went up to 2800 with a top speed in calm water of about 8.4k, much the same as when the boat was launched 18 years ago. We are pretty rigorous about opening the throttle to max every 12 hours or so.


We put about 290 hours on the engine and then left the boat ashore till this month. I changed the oil and fuel filters. We have twin Racors before fuel reaches the engine.


Having launched, with a spotless bottom and Autoprop, we  motored for about 12 hours at no more than 1900 revs.

Performance was perfect- up to 7.1k at 1800.    I then opened the throttle but with the lever full ahead the revs would not exceed 2100.  At 2000 revs we do 7.3k and at 2100 7.7k, what I would expect. But nothing above 2100.


More than that, on four occasions when I have tried full throttle the revs have fallen back  suddenly to about 1500, on one occasion stopping the engine.


I should mention that the refit included a new turbo , injectors and exhaust elbow and the fuel pump was sent off to Bosch who confirmed that it was fine


Diving on the prop shows that it is still spotless.


My thoughts are that there must be a fuel shortage when I open the throttle; that there is sufficient flow up to 2100  for the engine to perform correctly but above that there is fuel starvation.  I have changed both the engine and the Racor filters again, in case some fuel bug had grown over the winter and blocked them. The ones I took off were spotless and the fuel they contained was also spotless.


Anyone got any thoughts ?


Ian and Judy, Pen Azen, SM 302, Korfos, Greece


My thoug

Join main@AmelYachtOwners.groups.io to automatically receive all group messages.