philbzzz

Morning everyone. After a morning of investigation and checking I have (hopefully) found the culprit of the problem. By chance , I thought that while I was working on the engine I would change the oil and found that it was contaminated with diesel and had about 2 litres more fluid in it than there should be. My first thought was that the diagram on the lift pump had split but this was fine. I removed the injection pump and took it to a local diesel pump specialist who confirmed that the seal on the back of the pump is letting by. Basically, fuel is passing through it into the engine and oil entering into the fuel. I described the problem I've been having and he said that it was highly probable that the fault in the pump was the culprit as he'd seen it a number of times before. He offered to replace the seal while I waited (about £50) but I decided to have the entire pump reconditioned which will cost about £350. Seems a bit daft not to have it done whilst the pump is off. I also asked him to overhaul the injectors at the same time as they looked like they hadn't been done since 1971 when my boat was built ! Anyway, should be back in a couple of days so I'll keep everyone updated ...... Fingers crossed.

Thank you zenataomm , kind words indeed. I'm going to have a good look at it today but I've also ordered a vacuum pump/gauge so I can test the inlet side of the fuel system for leaks. Also, one thing that I've just noticed is that there is a second pipe from the remote fuel filter that feeds an old (and unused) diesel heater which could be letting air into the system. I'm going to cap this off just in case but will probably vaccum test it first as I'd be interested to know if this is the case. I'll report back ! Philip

Thanks for the replies, I'll check what you have suggested tomorrow and report back. ?

Hi there, I've got a problem with my BMC 2.2 diesel engine that is giving me no end of trouble - any knowledge or advice would be much appreciated. Basically, the engine starts fine with the normal amount of smoke which dies down after a short while. The boat runs nicely, doesn't hunt or miss and will run for over an hour whilst moored up either just on idle or revving the engine during the process. The problem occurs when I go up river. After about 10 minutes of cruising at a slow speed the revs drop . If I push the throttle forward then the revs pick up again but after a while they drop again. This happens repeatedly until the throttle is fully open but the engine is only doing perhaps 1000 rpm. The engine will then stall and not restart. After about 10 mins the engine starts and all seems fine but again it will do the same after another short run up the river. At no point is the engine overheating and is maintaining about 60 degrees when warmed up. So far I've done the following. Replaced fuel pump and all filters. Emptied and cleaned tank and put in fresh diesel. Cleaned air filter. Replaced fuel pipe on inlet side. Checked and cleaned tank vent (and tried with fuel filler open) Checked for diesel bug. Bled (several times) filters, injection pump and injectors. I'm really stuck on what it could be. Any suggestions? Philip