Diesel WON'T Start

[makomagic]

It's getting late in the season here in the NE and I need to get my Cummins winterized. If she does't start I will have to do it manually by flushing the raw water side of the engine.

Here's my issue. I had fuel from last season in my starboard tank and wanted to run her low prior to refilling at seasons end. My registers showed under a 1/4 tank. I now know this is a big NONO with diesels. Anyway, I think I ran the tank to where I picked up sludge or whatever.

Here's what happened. I started the engine, throttled up and she bogged down...almost as if someone cut your windpipe off. Then she would not restart. The engine sounds very weak cranking, although I changed batteries and show 13 volts. I cracked the injectors and the fuel is barely dripping out. I have an automatic prime and still the engine does not hold a prime. Initially, I thought there might be a starter issue...when cranking she runs down to 10 or less volts. I am told this is normal on a diesel. I also think it could be an injection pump. The injectors should spit, NOT drip.

BUT...what I am thinking first is that I have a clogged fuel line or two...if I ran the tank down. What is the method for cleaning / flushin the lines? Do I blow back into the tank or suck out? Is there a product that cleans this crap out of tanks? What type of pump do I use?

AND...do you think this could be the issue? I am thinking the tank is airbound, fuel line gummed up, bad injection pump or faulty starter.

A cummins guy tells me that he sees this issue with cummins and that there is a thunmb screw or something similar on the injection pump itself. Almost like a fuel shut off or solonoid that needs adjustment.

EXTREMELY frustrated

[Russ]

Did you change the fuel filter? If you have a Racor fuel/water separator any gunk you pick up should be trapped in there. Drain any water out the bottom and change the filter cartridge. Shut off fuel line while doing that to prevent loss of prime. Russ

[micky692002]

Check the screen that's supposed to be in the intake of the injection pump.

http://i26.photobucket.com/albums/c140/elburru/injectionpump.jpg

[makomagic]

Let me revert for a moment. The boat was running a bit weird. Under power I normally get 2200 rpm's at approx 18 knots and at WOT 2500 rpm's 21-22 knots. When this problem occured I could not get 2000 rpm's 12-13 knots at the pins.

I shut the engine down and when I re-started the boat...it fired...when I engaged the throttle and gave it a throttle boost she bogged down and stalled. At that point the boat would not restart. I realize (NOW) that diesels should not be run below 1/4 tank. I had fuel from last year and wanted to run it down prior to refueling at years end (fresh fuel). I bled the system according to the instructions in the Cummins manuel. The engine has fuel. Initially, with a squirt of ether I got a VERY brief kick. It will no longer give that lick with a shot of ether. Why?

I am not familiar with the screen in the injection pump. BTW...it is a Cummins 210 6BTA. Tonight I checked and blew out all fuel lines to be sure there were no clogged lines. On my manuel prime pump...it has little suction. I do have an automatic primer as well. It just doesn't completely hold a prime. Their is fuel in the injection pump when I crack the bleed screw. When cracking the injectors they are each topped off with fuel, but when I try to fire it...nothing more than a dribble. I am told they should spit with some fury.

Prior to blowing out fuel lines, it was not holding a prime very well, but it appears to be better once I blew out the lines, but still not great. Now I am concerned because the marina turned off power...hence no shore power available and it's tough no crank her to check pressure on the injectors.

I removed the fuel filter and the fuel is and filter is clean. Topped it off as well. The racor is full of fuel with some sediment at the bottom of the tank. Topped that off as well.

It appears that my starter has the appropriate voltage. I am concerned because I replaced the batteries and she seems to not have enough cranking power to turn the diesel.

I have been told that it could be either a starter or injection pump issue. Even with new batteries, it seems to be getting very weak starting power. There is fuel getting to the injectors, however. And, there is definetely fuel at the injection pump. I realize that it is VERY difficult to get your prime back when lost....I'm not positive if this is it.

Any idea how long an injection pump should last? Could there be a small crack in a hose causing an air problem? There is 1200 hrs on it.

Does ANYONE have ANY other suggestions??? MUCH APPRECIATED

[Pedlyr]

Bad fuel can ruin an injection pump. A local fuel injection shop can test it for you.

Now that it is cold out, your engine will be that much harder to start. As joc said, try a heater to warm things up.

I would put some CLEAN fuel in a bucket and try running out of that as close to the lift pump as you can get. Make sure you do not have a screen that is clogged as Micky suggested. Crack each injector line at the tip and turn it over. Make sure you have fuel at each cylinder.

Many times when sucking air the engine will surge or show high RPM's. Check all your hoses, etc.

Are you getting any smoke? Is the air filter clean? Does the turbo spin freely by hand? If you have an aftercooler, that could be clogged. Check the lube oil. Smell like fuel or coolant? Any water? Is the oil level high or "increasing"?

Finally, I would get rid of that old fuel. And engines can become addicted to either.

[Scratcher]

Don't use ether in the diesel; diesel fuel is itself a lubricant and ether will scrub the pistons clean of lube and do generally bad things.

Do what the others said and warm up the engine compartment with a space heater (be careful about too much heat).

Charge the batteries. Diesels start based on compression, not spark, so weak batteries and slow turnover are a real problem because they will not build the compression to the point that ignition occurs. IMHO this is the biggest of your problems right now.

I have the same engine. The only injector I need to crack is the one at the forward end of the engine in order to bleed air. I don't completely remove the fitting, I just back the fuel line off a turn or two and look for fuel dribling out.

One thing that happened to me was that the wire on the fuel solenoid came loose, but not off. This caused a loss of rpms similar to yours, and was next to impossible to diagnose. The fuel solenoid is on the engine behind the injector pump, check the wire going to it. l

I don't think you should have to blow lines out. If sludge or yuck got through the injector pump and into the supply lines then you have bigger probs. But, seeing that your filter (what micron is it?) is not clogged, it seems unlikely that sludge got through.

The loss of rpms on the earlier run indicates something else going on, not sure what. Maybe the solenoid wire, maybe clogged air intake, maybe clogged fuel filter.

Let us know how you fare.

[makomagic]

Well, I manually got it winterized. Ac couple of questions on the previous points you had made. My batteries are brand new and I am showing very low voltage on the guage at the helm. It cranks VERY slowly! I am thinking that my starter is creating some type of draw???

Sounds crazy, but is there any way possible (since you have the same engine) to better describe where that fuel solonoid wire behind the injection pump is? If I crack that first injector, what force should the fuel be coming throught the line. I had the line completely off and it barely dribbles. I appreciate your help - Mike

[Mistress]

That solenoid is on the block side of the injector pump about midlength. Kinda tucked up in there and can really only be seen by looking up. You'll see the wire that goes to it. The wire may be painted the same colr as the block, which makes it hard to see..but it's there.

If you remove the solenoid you can remove the tip from the plunger and reinstall. To shut the engine down you then need to move that throttle plate looking thing in front of the throttle.

I can't say I've performed the tests you want confirmation on...but the fuel from the injectors should do a lot more than dribble.

You might want to check out www.boatdiesel.com. Some really knowledgable folks over there. Worth the cost of admission.

[cloud9]

I used to have this Cummins model in my 26 express ... great engine!!! Definately, if you had the fuel line to an injector completely off (which you should not be doing), you should have gotten spurts, not dribbles. When bleeding a line, only back of the nut 1/2 to 1 full turn. Then if there is air in the lines, you can see bubbles blowing out. I think you may need to bleed the fuel supply line coming into the injector pump, since it seems your injector pump is not getting enough fuel. When no more air bubbles appear there, then bleed the injector pump itself with the bleeding screw on top of it. Then, lastly, bleed your injectors. I think you most certainly have air in your fuel suppy. Your racor filter should have been full already ... there should not be any need to top it off unless you drained some from the bottom. You may even have to hook up a bulb to the fuel port that leaves the racor filter, and try manually sucking fuel through the filter. Fuel supply problems are a PITA to fix in a diesel. That's why preventative maint is so important .... clean fuel filters, good diesel treatment (Soltron or PRI-D), and air tight fuel lines throughout. Good luck man .... I feel for yah. But at least you have nice cool weather to work in! :)

[kao58879]

My boat(perkin diesel) had similar problem before. The final fix was replaced all the fuel hoses(lines) due to weather crack, and make sure all connectors are tight. Good luck...

[skipm]

How did you make out? I put an electric fuel pump between the filters & the mechanical pump , when it has pressure pump the mechanical pump with the lever . When you start it use both batteries for a fast spin , .Crack the injectors you should see bubbles.If not, one of the 2 pumps is bad. Then process of elimination.