Friday, October 26, 2007

Fuel Issues

Changed Racor Fuel Filter
Changed Secondary Fuel Filter
Changed Crankcase Breather
Changed Air Filter

Replacing the shift cables went very smoothly, so my father-in-law and I finished that job faster than I had anticipated. That left time for a little more maintenance before Michele and her mother arrived for our trip over to Cambridge.

I've had some concerns about our engine recently. There was a noticeable power loss and an increasing amount of grayish smoke at cruising speed. That could be a sign of serious trouble (worn rings, bad or dirty injectors), or possibly just a fuel problem. I was considering calling a Volvo diesel mechanic, but wanted to get all the filters changed out first, to determine whether it was just a fuel problem.

We quickly changed out each of the filters: the Racor primary fuel filter, the secondary fuel filter on the engine, the crankcase breather, and the air filter. During this process, I also discovered that my prior difficulty bleeding the fuel lines wasn't a problem with the lift pump after all. Instead, it was "operator error" -- i.e., I wasn't doing it right. The pump lever has some play, and I was only moving it within that range. To actually work, it needs to be pushed down beyond that range, at which point it springs back up. I was very pleased to learn this and gain the peace-of-mind that comes with now fully understanding the bleed process in case I ever need to do it while out on the water.

I'm happy to report that this effort made a huge difference in engine performance. Our speed was back up, the engine ran smoothly, and the smoke was virtually gone. We're still only hitting ~3400 RPM instead of our rated 3600 at wide-open-throttle, but that may just be a result of marine growth on the hull, so I'll wait until we launch in spring with fresh bottom paint to determine whether there's a problem.


Replaced Flybridge Cables, 10/13/2007

On my trip with Chris, the flybridge shift cable broke during our anchoring maneuvers. It broke in forward gear, with the anchor plus 20' of chain and 30' of rope in the water off the bow. It was an exciting few minutes, and an important lesson not to postpone maintenance. The flybridge shift and throttle cables had been a little stiff for quite a while, and I was planning to do the replacement during the off-season. Surprise! This project is getting done ahead of schedule!

The cables are 3300-universal type, 10' long, and run from the flybridge controls to the lower controls. They are threaded on both ends, making attachment/adjustment fairly easy. I replaced them with new TFXtreme #CC63310 cables, from Teleflex Marine. People rave about these cables, and I found them at for just $30 each.

My father-in-law, who is a whiz with all things mechanical, helped me install them. It was fairly straightforward job:
  • Removed the cover plates on the engine controls at both stations. There are set screws on each side, just above where the handles attach, that hold the cover in place.
  • Detached the throttle cable by removing the cotter pin and spinning off the threaded fitting that holds the cable at each station. (Chris and I removed the shift cable the prior week, so I could take it home and find a new one.)
  • Taped the new cables to the throttle cable and snaked them through from the lower helm up to the flybridge.
  • Attached the new cables. On this boat, the fittings on the flybridge are not adjustable. Once threaded on and attached, they do not turn, whereas the lower helm fittings turn with a screwdriver.
  • Adjusted the cable travel so that the shift and throttle levers hit their stops in both forward and backward positions, and so that the shift control is in its neutral detent at both helms.
  • Lubricated the controls with WD-40.
  • Reattached covers.
What an amazing difference! The TFXtreme cables allow a 4" bend radius, whereas other cables support only an 8" bend radius. Ours required a pretty tight bend at the lower station, so I think these cables were a great choice.