Good point. Keep in mind most A4s dont have a heat exchanger since they are raw water cooled. When I cleaned out my water jacket I found two small impeller pieces inside the block. However, I found several pieces wedged in the by-pass inlet fitting of the thermostat housing.
~Dan --- On Wed, 6/23/10, David Savlin <[email protected]> wrote: From: David Savlin <[email protected]> Subject: Re: [IC27A] A4 fun stuff To: [email protected] Date: Wednesday, June 23, 2010, 10:41 AM Hi Doug -- if there were no vanes left on the water pump impeller, that probably means they broke off and have been pumped into the heat exchanger, where they can block the flow and cause overheating. There have been other messages in the past on this (as you guessed) so I will simply say that others have written about taking the end cap off their heat exchanger and fishing out the bits of impeller -- and doing a descaling / cleaning while they were at it. Best wishes, David On Wed, Jun 23, 2010 at 8:56 AM, Doug <dj2...@yahoo. com> wrote: I'm sure this has been discussed in the pass but new to me. I've had a series of little problems with my Atomic 4 that I'm happy to say it is running again, for now. The first was the engine not turning over which I thought was the battery not being charged. Turns out the starter solenoid was the culprit. Fixed by (i believe) rotating the battery connection at the solenoid. Eventually I will replace it with the new spare. The second was engine quitting while trying to return to slip. The electric fuel pump just kept running indicating no fuel. When I finally got back to the slip I disconnected every thing and thinking the pump was bad took it off too. Did I mention I don't like gas? Managed to get gas on me and the boat. I took out the fill tube, valve out of the tank to see if that was clogged. Contacting Moyer Marine for a fuel pump purchase I was told that the pump was probably good and that there was a siphon break so place. The only thing I found was the check valve (anti-siphon valve) might have been stuck. Everything went back together and it worked great. The third thing was looking over the stern and realizing no water coming out of the exhaust. So off came the water pump back plate. Sure enough there were no vanes left on the impeller. Lucky for me the previous owner had a spare new Barco. Looks a little different but seams to work. This all happened with in a week. It has been so hot in the afternoons I've had to go down at first light to do the work and then hightail it back to my job. Hopefully this will be all for awhile because as you all know working on an inboard on the C27 is a bear.
