As mentioned in a previous article, I bought a project which looks like a sailboat. I made an attempt to start the engine in December of 2015, on what has proven to be the coldest day in 2015 and, so far, the coldest day in 2016. Needless to say, the engine wouldn’t start. This old boat has a 1979 Perkins 4-154 which was built without glow plugs.

Now, just prior to this failed attempt to start the engine, I had re-routed the valve cover vent tube. A previous owner had decided to connect that tube to the engine air intake. The end result was crankcase oil being sucked into the intake manifold and the air intake screen being plugged with crankcase oil.

After re-routing the vent tube and cleaning the air intake screen is when I attempted to start the engine (on the coldest day of the year) and failed. Then began a longer than it should have been process of troubleshooting the cause and eventually starting the engine.

I first checked the tank to make sure more than 160 gallons of diesel hadn’t suddenly disappeared from the tank. Next, I held my hand above the intake manifold while someone else pressed the starter button, to confirm these was still vacuum and no backflow out the intake manifold. Since the only thing remaining was fuel to the injectors, I loosened one fitting and had the same person press that starter button. I saw fuel spurting out so I admitted to being stumped. I assumed at this point that it was just too cold for the fuel to ignite.

Since the engine doesn’t have glow plugs and since I was hesitant to use starting fluid, I found a heat gun. I used it to warm the injector pump, the secondary fuel filter and the injectors. I then rigged it so it would blow hot air into the intake manifold while I pressed the starter button myself. Still, not a peep out of the engine.

I decided to do some more research on using starting fluid with diesels. I found a consensus that starting fluid can be used with diesel engines, but one must be careful. Before using starting fluid, confirm the following:

  1. any glow plugs are cold
  2. any intake manifold heater is cold
  3. there’s not other source of heat or spark which could ignite the starting fluid

Then, while someone engaged the starter motor for five to ten second bursts, I sprayed very small bursts of starting fluid toward the intake manifold. Each time we did this, the engine would fire, burn the starting fluid but not actually start.

I was still missing something, so I decided to walk away and await inspiration.

I returned the next day. I had never actually inspected the fuel lines or filters myself. The boat was delivered to me and the fuel had been polished and the filters had been replaced before motoring all the way up the California coastline without any trouble. However, when I finally crawled into the engine room and shined a flashlight into the sediment bowl of the primary fuel filter, I saw that it was full of mud. I opened the drain petcock on the bottom of the bowl, but absolutely nothing came out. I had found my culprit.

I opened the primary filter body, removed the black (formerly white) filter cartridge and then removed the entire body from the fuel lines and the engine room. I disassembled the body and scooped out all of the mud. I used a grease solvent to clean the body and sediment bowl before reassembling it and re-installing it in the engine room. I added a new filter cartridge and filled the entire body with fresh fuel. Since I had a spare handy I also replaced the secondary fuel filter, after first filling it with clean fuel too. I didn’t learn about it until later, but I now know there is also a screen on the input of the fuel lift pump, which I should clean too.

After bleeding the secondary filter, then both sides of the injector pump and finally all four of the injectors, I attempted to start the engine again. After about 30 seconds of cranking, on a day which was also about 20 degrees F warmer than the initial attempt, the old engine started and ran very well. Just as preventive maintenance, I added some biocide to the fuel tank, just in case it still had a bacteria colony, even after the polishing.

The last thing I did was to recently test the performance under power. Prior to all of this fuel filter adventure, I was concerned about the speed under power. The best I had been able to achieve, in optimal sea and wind conditions, was about 5.5 knots. Yesterday, I easily ran the engine up to 3,000 RPM and was able to quickly make 7.5 knots under power.

Time well spent!