Hello everyone,
Just back from a week-long cruise here in northern Lakes Michigan and Huron and had a bit of trouble that I hope you can help with.
The trouble is that my engine stalled four different times - all different days. This has never happened before. I have a Universal Diesel M35B. It originally happened first thing in the morning after leaving a marina (two times in a row), once in the middle of the afternoon after motoring for about an hour, and once after 6 hours of motoring. The waters have been both dead calm and moderately heavy. I have clean filters and fresh fuel. My Racor filter bowl appears clean with no sediment or water (but I haven’t drained it). Engine temp has been running normal.
The engine doesn’t kick and fight and sputter, but it just slowly winds down. One thing I noticed on the last stall was that the RPM’s were frozen at 2200 where I had the engine set for motoring - similar to what it does if the key is turned off while the engine is running. After letting it sit for a couple of minutes I was able to start it up again and it ran strong for several hours.
I’ve cleaned out the fuel tank vent line so it is clear and gave all of the electrical connections a brief once over and don’t notice anything out of place.
Any thoughts or ideas are appreciated. Makes me very worried when the engine doesn’t work!
Thanks,
Steve Hall
NS30U 510
Mariner’s Cat III
Suttons Bay, MI
The first suspect is fuel. Possibly an air leak. or some gunk at the bottom of the fuel pick up. The fuel pick up is easy to check.
Other possible cause is a weak lift pump. These are electric pumps on a Universal engine so check it is well grounded and making a clicking sound when the ignition is turned on. You can also check for air leaks by taking the flow side off and turning on the ignition and let it pump fuel into a can. If you see air bubbles, tape each connection one at a twim starting at the tank. When the bubbles stop you have found the leak.
Hi Steve, just to get a bit more background…what was the fuel level in your diesel tank when these failures occurred? We had a similar problem and it was traced back to the fuel pick up hose inside the tank. It turns out that the stock pickup hose is actually pressed onto the shut off elbow nipple inside the tank. Back and forth motion over the years loosened the hose ever so slightly. When the tank was full…no problem, but as the fuel level went below the connection the fuel system started to suck air. Eventually the engine would quit.
Another stalling issue was caused by a clogged filter in the Racor. The engine would wind down and eventually stop. After a few minutes it would always start again. Like you, I had changed all the filters on the engine not knowing that there was another one inside the Racor.
Hope this helps…Ron
Ron & Diane Schryver
“Alpha Waves” NS30U #393
Georgian Bay Midland ON
I have an M-35 and remember a problem that seemed similar to yours. It turned out that replacing the bleed valve solved the problem. The clue was that it would occasionally leak bit of diesel fuel. If I remember correctly the valve cost about $45. I have a photo. The valve is the new looking part in the center of the photo.
Hi Steve,
I went through this a number of years ago. When it occurred I changed the main filter and things were fine. For a while.
Off season I did the following:
Totally emptied the fuel tank.
Installed two 10" aircraft inspection ports, one at each end of the tank. Once the initial holes were cut I could lower a light and totally clean one end, then reverse and clean the other.
I went to Irish in Charlevoix and discussed fuel additives, which I now add at each refueling. I’d have to check on the boat to tell you the brands.
When I refueled I added the diesel in 5 gallon increments. I bought 4 cans to transport it. (With each five gallon fill I marked the fuel gauge. This has made refueling much easier to determine the amount of additive to add.)
I changed all three fuel filters.
Since then I refuel at season’s end and haul out.
I religiously replace all three fuel filter each Spring before launching.
It’s been 7 or 8 years without any problems, save one. When I changed my Racor filter this Spring, I used my last one. Normally I have 3 or 4. I’m trying to find a good source to restock and am not having much success. Perhaps those reading this can let me know a source with a reasonable price. Or if it’s just better to update the filter.
Phil Harmeson
1985 NSU30
Cartharsis.
Traverse City, Mi
Steve: Was the lift pump clicking with the key on and engine not running?? Also, I can’t seem to equate the tach stuck at 2200 having anything to do with the engine unless the power source to the control panel was lost due to a bad connection. That could cause those two symptoms since it would stop power to the lift pump and power to the tach. In addition, you said the tach stays at the current speed when you turn the key off. I assume you know never to turn the key off before you shut the engine down,
Joe Valinoti
S/V iL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA
If it’s an electrical problem - does you engine have a oil pressure alarm? Does it go off when the engine stalls and stops as the alarm should? If it doesn’t then the “ignition” power that runs the fuel lift pump (if the M38B has a lift pump ) and the oil press alarm and the tach may be intermittent.
Phil - I remember you having trouble awhile back. Maybe I can check out your inspection ports sometime?
Joe - I am not sure about the frozen tach either. I thought the same thing about power to the panel or perhaps a bad ground, but can’t seem to find either. I didn’t pay attention to the lift pump clicks when I was stalled…I was just trying to not get hit or hit anybody.
I am not in the habit of turning the key off first, but it’s been done before. What trouble does it cause other than shutting off the alarmas and lift pump? I drove an old farm tractor that always had the key shut off after starting.
thanks!
Steve Hall
NS30U 510
Mariner’s Cat III
Suttons Bay, MI
