Mister P is running again. Initially, the idle was high (around 1200 rpm) but was easily adjusted to 750 rpm. The shop manual recommends 650, but I see no point in having the engine shake its mounts at that low speed.
It took several attempts to start. I bled air out of the fuel system but I was ignorant of the second bleed screw on top of the injector pump's “anti-stall device”. Raven’s pump is a hybrid of the two drawings in the shop manual, and neither showed this type of bleed screw. After talking with two other Perkins owners, I decided to loosen this screw.
But first … I had to modify an Allen wrench to fit between the screw and the heat exchanger. Have you ever tried to hacksaw through even a small Allen wrench? After twenty minutes I had barely scratched its surface. Friends on Brendan bailed me out with the loan of their Dremmel. (Mine is in storage, of course.) Unable to get any Allen wrench to fit, I had to guess which one to cut ¼” off. Third wrench was a charm.
Bleeding out the air was becoming second nature. Eventually, one cylinder fired, then another … Once all four were firing, I shut down the engine and opened the raw water seacock. I had closed it to keep from filling the wet muffler with sea water while I was repeatedly cranking a reluctant engine. Thankfully, I remembered to open it. In Bellhaven, NC, two years ago, I was so elated after effecting an engine repair that I forgot to re-open the raw water seacock, causing the engine to overheat, the cabin to fill with sweet-smelling steam from boiling antifreeze, and Hilde to go in search of Raven’s fire extinguishers.
When they are running well, diesel engines at idle sound like they have a heartbeat. It was almost as if I had breathed new life into some living beast. (Steam engine enthusiasts will easily understand this.) Naturally, I am very happy that there seems to be life in the old dog yet.
CD36 owners with the 4.108 engine and the one-piece, aluminum, Bowman casting that is a combined exhaust manifold, heat exchanger, and antifreeze header tank on the engine’s port side might be interested to know that this assembly can be removed and reinstalled without removing the injectors and the high pressure fuel lines. (Write me for details.)
Raven’s heat exchanger was designed with no zinc, so I added a bushing and pencil zinc at the rear of the casting. (On the right in the picture, just below the lazarette hinge.) It is easy to reach to check and replace, if necessary. I don’t know if I did it right, but the corrosion on the heat exchanger indicated that some sort of sacrificial zinc was necessary. (Write me for details.)
The exhaust goose neck, from the rear of the manifold to the wet muffler was heavily rusted. It is made of standard 1½” galvanized plumbing pipe, elbows, and connectors. It has worked flawlessly for 24 years, so I can’t knock the design. To remove the rust, I first tried Naval Jelly. It did only “OK” so next I dipped it in muriatic acid, diluted 1:5 with water. This is nasty, nasty stuff. I was my first experience of it and, I hope, my last. For all that, it worked wonders on the exhaust pipe, removing the rust and calcium so that the original pipe threads are again visible. After neutralizing the acid in a bath of water and baking soda and allowing the pipe to dry, I wire-brushed it vigorously. The Houston air was so damp that surface rust began forming almost immediately, so I painted it with Ospho to stabilize the surface. The final coat is Duracolor’s high temperature, ceramic-based paint. It is rated up to 1200°F and sprays on like chromium plating. It was very satisfying to see the exhaust pipe shining like polished silver. I have run the engine over an hour already and the pipe is still shiny.
Diesel Parts Sales on Canal Street in Houston did an excellent job of rebuilding the pump and atomizers, and refurbishing the heat exchanger. They took the time to answer my questions patiently and willingly shared their encyclopedic knowledge of Perkins engines.
Now that all that is behind me, I hope to bring Raven to Corpus Christi next week. Watch this space for our progress.
Best regards,
Captain Dave
It took several attempts to start. I bled air out of the fuel system but I was ignorant of the second bleed screw on top of the injector pump's “anti-stall device”. Raven’s pump is a hybrid of the two drawings in the shop manual, and neither showed this type of bleed screw. After talking with two other Perkins owners, I decided to loosen this screw.
But first … I had to modify an Allen wrench to fit between the screw and the heat exchanger. Have you ever tried to hacksaw through even a small Allen wrench? After twenty minutes I had barely scratched its surface. Friends on Brendan bailed me out with the loan of their Dremmel. (Mine is in storage, of course.) Unable to get any Allen wrench to fit, I had to guess which one to cut ¼” off. Third wrench was a charm.
Bleeding out the air was becoming second nature. Eventually, one cylinder fired, then another … Once all four were firing, I shut down the engine and opened the raw water seacock. I had closed it to keep from filling the wet muffler with sea water while I was repeatedly cranking a reluctant engine. Thankfully, I remembered to open it. In Bellhaven, NC, two years ago, I was so elated after effecting an engine repair that I forgot to re-open the raw water seacock, causing the engine to overheat, the cabin to fill with sweet-smelling steam from boiling antifreeze, and Hilde to go in search of Raven’s fire extinguishers.
When they are running well, diesel engines at idle sound like they have a heartbeat. It was almost as if I had breathed new life into some living beast. (Steam engine enthusiasts will easily understand this.) Naturally, I am very happy that there seems to be life in the old dog yet.
CD36 owners with the 4.108 engine and the one-piece, aluminum, Bowman casting that is a combined exhaust manifold, heat exchanger, and antifreeze header tank on the engine’s port side might be interested to know that this assembly can be removed and reinstalled without removing the injectors and the high pressure fuel lines. (Write me for details.)
Raven’s heat exchanger was designed with no zinc, so I added a bushing and pencil zinc at the rear of the casting. (On the right in the picture, just below the lazarette hinge.) It is easy to reach to check and replace, if necessary. I don’t know if I did it right, but the corrosion on the heat exchanger indicated that some sort of sacrificial zinc was necessary. (Write me for details.)
The exhaust goose neck, from the rear of the manifold to the wet muffler was heavily rusted. It is made of standard 1½” galvanized plumbing pipe, elbows, and connectors. It has worked flawlessly for 24 years, so I can’t knock the design. To remove the rust, I first tried Naval Jelly. It did only “OK” so next I dipped it in muriatic acid, diluted 1:5 with water. This is nasty, nasty stuff. I was my first experience of it and, I hope, my last. For all that, it worked wonders on the exhaust pipe, removing the rust and calcium so that the original pipe threads are again visible. After neutralizing the acid in a bath of water and baking soda and allowing the pipe to dry, I wire-brushed it vigorously. The Houston air was so damp that surface rust began forming almost immediately, so I painted it with Ospho to stabilize the surface. The final coat is Duracolor’s high temperature, ceramic-based paint. It is rated up to 1200°F and sprays on like chromium plating. It was very satisfying to see the exhaust pipe shining like polished silver. I have run the engine over an hour already and the pipe is still shiny.Diesel Parts Sales on Canal Street in Houston did an excellent job of rebuilding the pump and atomizers, and refurbishing the heat exchanger. They took the time to answer my questions patiently and willingly shared their encyclopedic knowledge of Perkins engines.
Now that all that is behind me, I hope to bring Raven to Corpus Christi next week. Watch this space for our progress.
Best regards,
Captain Dave
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