Perkins M50 Problems

[bpre...@ns.sympatico.ca]

We own a 1985 Beneteau Idylle 11.5 which we re-engined in 1998 with a
new Perkins M50 as a replacement for the original Perkins 4108. In
the summer of 2004 the engine was burning lube oil and in consultation
with the authorised Perkins repair company here, we decided that the
engine needed to be re-built to solve the problem. During the winter
of 04/05 the engine was removed from the boat and on removing the head
it was discovered that #1 cylinder was wet with lube oil and it's
valves and head were choked with carbon. The valves for the other
cylinders had some carbon build-up but # 1 was really bad. The
beaings, cylinder walls, pistons, etc were all in excellent condition.
The engine had 725 hours on it when we had it removed. Since
re-installing the engine in the spring of 05 we have been having
continuing problems with it being very hard to start and once it does
it smokes very heavily and leaves a fuel slick on the water. We have
had the valve timing and fuel pump timing checked and re-set, the glow
plugs checked, injectors tested, high pressure fuel pump removed and
tested and still can't solve the hard start and smoke problem. So at
this point we have an engine with less that 750 hours on it that takes
about 10 minuted of glow plugs and cranking to get started and then we
look like a bug fogger....costs are mounting, we are totally frustrated
and our mechanic (also very frustrated) is wondering at which point we
need to stop pouring money into this engine.
Does anyone have any similar experiances and ideas on what to do?

Bernard Prevost
Esperanza II
Halifax, NS, Canada

[Jon McClain]

Aaaa, give me a Yanmar! Do to a timeout for a surgery our ten year old
OC321 with 27 HP Yanmar sat idle in the water for over 3 months. It
started on the first touch of the button and it never smokes.
Jon McClain
s/v Parrot Tales, OC321, #77

[Bill Jarvis]

The fact that you have oil in the combustion chamber and that the engine is
hard to start would indicate to me that the compression on #1 cylinder is
low. That could be rings or valves. I would start by checking the valve
clearances and if they are within spec I would have the cylinder compression
checked.

If it is low you may have either stuck or broken piston rings.

Bill

[Force Majeure]

There is a cold start circuit on this engine that changes the fuel
timing advance. Have you checked that? It could be stuck. While
that could affect starting, especially that far north, eh, I don't know
how it would contribute to the oil problem. FYI, The Perkins Prima M50
is a derivative of the Austin/Rover O-series engine, and was used in
the Maestro, etc., in Europe. It has a great reputation as a long
life, low problem automobile engine, and your engine has low hours.
The Brits use these engines extensively for repowering old Land Rovers,
and there are many forums on the web where these guys chat about their
issues/problems, etc. I'd post the problem up there and see if anyone
from that "world" can help. Just google Perkins Prima, and you will
find the sites.

I have the M80T, which is the turbo version of that engine, and it was
really smokey when I bought it, but it turned out to be old fuel and
sluggish injectors. A few tanks of new fuel with injector cleaner
fixed it up.

[bpre...@ns.sympatico.ca]

We have had the HP fuel pump and valve timing checked but I'm not
certain about the cold start circuit....however if it is stuck in cold
mode I wonder why the engine is so hard to start. I'll give the
mechanic the suggestion abt the cold start circuit and keep my fingers
crossed.

Thanks

Bernard