Ed Stone writes,
Our Grand Slam’s starboard motor’s Shut Off system has been unreliable for several weeks; it became time to diagnose and fix it. I posted a question on this blog, to which Lee Dahlen replied “call me and I’ll talk you through how to diagnose the problem! That is the Lee I know; always ready to help!
When I did phone he was up to his ears in a client’s engine room; he would call back in a few. While waiting the talk I removed the starboard engine Shut Off switch, disconnected the wires; there are two, one from the starter switch to the fuel shut off switch, the other from the fuel shut off switch to the motor. Then tested the switch for continuity with a multi-meter and got the results without switch engaged, and again with the switch engaged. Lee phoned a short while later and we discussed the meter results, and opined that the switch operated correctly, providing electricity through it when the switch was pulled to activate; that meant that the problem was in the solenoid, which was not unusual. So, I reinstalled the switch into the dashboard. Lee told me to listen to what the good switch caused at the top of the port motor, and that would point me to the right component to look for on the faulty starboard motor. Sure enough; after pulling the salon deck’s removable floor panel over the motor, I bent over the top of the motor while Marcia activated the switch; the loud metallic knock was unmistakable; we identified the fuel shutoff solenoid, a small round 2.5″ X 3.5” “can” shaped part at top center between the cylinder heads. I repeated the test on the starboard side, and sure enough, that motor’s solenoid did not produce the same sharp metallic sound.
Removing that defective solenoid assembly was easy enough; two bolts had to be removed that held the solenoid attached to the bracket where it connected with the fuel shut off arm with a fork at the end of it. Once the bolts were out, the top plate could be removed to expose the mechanical connection, and then the assembly could be maneuvered to pull it out of its position. The solenoid had two electrical connections, with one stud marked S with the wire from the switch attached; the other wire was a ground wire from the solenoid to a point at the top of the motor. On the side of the solenoid was stamped “24 – 32 VDC” which was important; our motors run with 32VDC. I took photos of all of it and emailed them to Lee, along with a copy of the Caterpillar dealer’s $350 quote for a replacement. Later in the evening Lee told me that the solenoid appeared to be a common truck starter solenoid that could likely be rebuilt by a local alternator or starter rebuild shop for much less than Caterpillar’s new part price.
The following day I showed the solenoid assembly to a master machinist / prototype build manager out in the shop who also rebuilds cars; he thought he had one on a shelf in his home shop. An hour later he emailed with a link to the exact same part in new condition on the Ebay website for $29 plus $8 shipping! We bought 2 of the 10 that were for sale! They will be delivered in a week!
So, why did I take the time to share this story… it was because Lee Dahlen is always out there to help those of in the Commanders Club; like many other similar stories, he told me how to check the switch, then how to find the bad solenoid, and then what to do to avoid Caterpillar new part’s price. If Lee had not told me the bad part could be rebuilt, I would have never showed it to Rich, and would have not known about the exact “new” solenoid I needed was on Ebay at such a good price!
Thank you Lee!!!!!**
**You can view Ed’s original post here.