Fuel injectors (05/2019)
My C270 has the Westerbeke 20B Two engine.
It has been running well, no complaints. To set some context:
- No smoke visible on startup or under load.
- Started easily when cold (1-2 seconds cranking if glow plugs
used, 3-5 seconds even without glow plugs).
- Ran all day (8+ hours) with no hiccups.
- Good throttle response and power.
However (there has to be a 'however' or I wouldn't be writing this
page!), over the last year or so I had been noticing one trouble
indicator: When cold, the engine rpms didn't respond very linearly
to throttle input. After it warmed up, throttle response was
very linear. The problem was only
during the first minute or two after a cold start.
It wasn't really a problem since I let the engine warm a minute or
three anyway. By the time I was ready to cast off it was fine. So I
was able to ignore it for quite a while but it kept nagging me.
To be very specific: about a year ago if I started the engine cold,
it would start right up and idle around 800rpm. If I moved the
throttle up just a bit, the engine stayed at 800rpm. I had to move
it a bit more and then it would jump to 1000rpm. From that point on,
each mm of throttle movement would raise the rpms.
About six months ago, on a cold start, if I raised the throttle up
to the 1000rpm position the engine would still stay around 800rpm. I
had to raise it more, up to around the 1500rpm position, before the
engine would react and move up to 1500rpm.
Last month the problem got so severe there was no more ignoring it.
When cold, I could open the throttle to about 90% and the engine
would still remain at idle!! After a certain point (say, about 95%)
the engine would finally react and race up to 3000rpm. Even
then, as soon as the engine warmed up it was back to normal.
I could not find anything on the web or in books matching these
symptoms, so I'm writing this page in case it helps someone who
I removed the injectors and started looking for a place to test
them. Most places I contacted never got back to me... The few that
did, said they didn't know how to deal with marine engines and/or
Finally I found a place, Diamond
Diesel & Turbo Service, in Oakland (California) who said
they could check them out. I dropped off the injectors and they
recognized them on sight and said they had parts in stock and could
do the work right away. They cleaned, tested and rebuilt (replaced
the nozzles) the injectors in an afternoon. If you're in NorCal,
Turns out the Westerbeke injectors are Denso 93500-3840, FYI.
Here's a pic of the cleaned injectors:
After installing the rebuilt injectors, throttle response on
a cold engine is now perfectly linear.
my Catalina 270 page.