CAT 3208 turns over will not start...

[Osprey69]

Myself, mechanic and now a third trying to run down, what I am sure, is a simple relay switch or what have-you preventing fuel from getting to the engine. Checked all the usual suspect grounds, connections, ignition wires and switches. Switched shut-off solenoid from functioning to port engine.

No joy.

Ran perfectly well until no start one day. Now? Spins without even a cough.

Either we are not smart enough to find the simple solution or we are overanalyzing.

Yes the fuel lines are open.

 

[RT Firefly]

Greetings,
Mr O. Are there any obstructions in the fuel system (collapsed feed lines, disintegrating feed lines whereby a broken off chunk has clogged something, blocked tank pick-up tube)?

All a diesel needs, basically, is fuel and air unless an "improved" model has a bevy of controlling electronics.

 

[tiltrider1]

If a mechanic is having an issue sourcing the problem, it’s not likely we can help.

Just in case some one missed one of the basics let’s review a few things. Is there fuel in the tank? Are all the valves in the open position? Have you primed the engine to confirm there is fuel to the High Pressure Pump? Have we confirmed that the fuel shut off solenoid is functioning?

 

[slowgoesit]

Perhaps a little more information.

Was this a sudden thing? By that I mean did you stop the boat for lunch, then attempt to restart 30 minutes later? Or did it quit while running?

Did you recently change fuel filters?

Has it been some time since you last started it?

Is the boat new to you?
Do you have multiple fuel tanks? How about a crossover valve between tanks?

Need more info before we can offer possibilities . . .

 

[Osprey69]

Thanks all...

Ran at dock. When re-start no joy a week later.

All filters changed last fall.

Not new to us. Ran fine CT to FL last fall.

Single tank

 

[CharlieO.]

Are you getting fuel to the pump?

 

[Solly]

Pull a fuel line at an injector to make sure it's getting fuel. Preferably with an injector to make sure it's squirting. If not, bleed again.
Also it needs a healthy crank. Check the batteries. Parallel the house and start bank for more juice.
If it gets fuel and cranks fast enough it will fire, unless you have no compression....

 

[SteveK]

Another thread different engine same issue.

What means stops the engine. Look there. Operate that manually

 

[Portage_Bay]

If it ran fine before, no changes, assuming your mechanic checked fuel level in the tank, valves, primed the engines and checked for leaks leaks then your problem may be the fuel control solenoid. It is located on top of the fuel pump.

Are your engines energize to run or energize to stop? If they stop by tuning the key off they are energize to run. If you stop them by pushing a stop button they are energize to stop. Some marinized Cat 3208s are energize to run.

If energize to run:

• Locate the fuel run solenoid on top of the fuel pump.
• Have an accomplice turn the key to "run" not "start" then off again while you listen to the solenoid. Maybe even put your hand on it to determine if it is working.

If energize to stop:

• Locate the fuel stop solenoid on top of the fuel pump.
• With the key in the run position have your accomplice operate the stop button
• As above listen and hand on the solenoid
• Check the operation of the manual stop plunger on top of the solenoid.

Problems can be stuck solenoid, low or no voltage. i think there is a relay between the key or stop button and the solenoid. That may be faulty.

If your mechanic hasn't checked the solenoids then you haven't got a Cat 3208 experienced mechanic.


Edit: One more thing. If the solenoids are not working don't rule out the key switch and push to stop button.

 

[Osprey69]

Portage. We swapped out running port fuel shut-off solenoid and no joy. They were both replaced (at my instruction as one was suspect at engine survey) last fall. We have been dancing all over those connections as well.

Well check fuel flow just to make sure.

Thanks.

 

[Portage_Bay]

You've got quite a puzzle. Please post the solution when you find it. I'm still learning about my 3208s. Have you been to boat diesel?

 

[jungpeter]

Myself, mechanic and now a third trying to run down, what I am sure, is a simple relay switch or what have-you preventing fuel from getting to the engine. Checked all the usual suspect grounds, connections, ignition wires and switches. Switched shut-off solenoid from functioning to port engine....

Hi Osprey69. Any chance you have a built-in fire extinguishing system in the engine room? 3208 CATs use +12VDC to actuate the stop solenoid at startup, which must be maintained for the engine to run. Often, a fire system will have an auto-shutdown feature to open-circuit the +12VDC provided by the starting circuit in case the extinguishing system is actuated. If the fire system auto-shutdown feature has failed (lost it's brains somehow), it will leave the stop solenoid in the "stop" position, irregardless of the starting circuit. And often this part of the engine electrical system is VERY difficult to trace and diagnose.

So, simply swapping a known-good solenoid into the circuit is useless, unless +12VDC is maintained while the engine is cranking and running. You might jump +12VDC to the stop solenoid to verify it is open, and stays open during engine startup. This will at least remove this part of the fuel system from question. Given you seem to have a "worked yesterday, today it doesn't" issue, methinks an electrical open circuit has surfaced.

Regards,

Pete

 

[High Wire]

My non- cat two cents… it’s missing power to the run solenoid. Use test jumper leads right off the starter though a mechanic should have already done that. It should click with a loud snap.

 

[SteveK]

You are dependant on electric.
Portage and I are pointing to suspect problem.
The solonoid moves something mechanically. That is what may be stuck. Assuming solonoid was heard operating.

 

[fgarriso]

Loosen the fuel injector nuts holding the fuel lines. Then crank the motor a few rounds. There should be fuel coming out of each of the lines at the injectors.

 

[MYTraveler]

I would try starting fluid (WD40 works), but make sure that is OK for your engine.

 

[Doodie99]

If it ran fine before, no changes, assuming your mechanic checked fuel level in the tank, valves, primed the engines and checked for leaks leaks then your problem may be the fuel control solenoid. It is located on top of the fuel pump.

Are your engines energize to run or energize to stop? If they stop by tuning the key off they are energize to run. If you stop them by pushing a stop button they are energize to stop. Some marinized Cat 3208s are energize to run.

If energize to run:

• Locate the fuel run solenoid on top of the fuel pump.
• Have an accomplice turn the key to "run" not "start" then off again while you listen to the solenoid. Maybe even put your hand on it to determine if it is working.

If energize to stop:

• Locate the fuel stop solenoid on top of the fuel pump.
• With the key in the run position have your accomplice operate the stop button
• As above listen and hand on the solenoid
• Check the operation of the manual stop plunger on top of the solenoid.

Problems can be stuck solenoid, low or no voltage. i think there is a relay between the key or stop button and the solenoid. That may be faulty.

If your mechanic hasn't checked the solenoids then you haven't got a Cat 3208 experienced mechanic.


Edit: One more thing. If the solenoids are not working don't rule out the key switch and push to stop button.

I would say this advise is spot on.
On my 3208 it has a relay between the key and the energize to run solenoid. That relay could fail or have a bad connection.
On mine when i turn on the key the solenoid get 12V(12v system)
if you have a stop button turn on the key and press the button. this is likely a energize to stop engine and if it's getting 12V when you press the button it likely it not electrical other than the solenoid may be stuck.

 

[tiltrider1]

What we all agree on is that the engine is not getting fuel. Cracking an injector line will confirm what we already know, no fuel. Now if there is fuel what it will tell us is we have a catastrophic failure but that appears to be unlikely. You can either start at the injector and trace backwards or you can start at the tank and move forwards sooner or later you will have fuel on one side and not the other, at that point you will have found your problem.

I am still confused by the fact that you had a mechanic look at it and he wasn’t able to quickly pin point the source of fuel stoppage.

 

[koliver]

Solenoids sometimes behave when whacked with a hammer.

 

[TowLou]

Verify your fuel selnoid is getting the right power or dropping out. Then id check for fuel at the injectors by cracking a fuel line while cranking. When were the fuel filters changed last? Did they start to let air in? Got a manual fuel prime pump?

 

[TowLou]

Solenoids sometimes behave when whacked with a hammer.

Ill agree.

Had a natural gas genny today with the shutoff fuel selnoids sticking closed at startup....... Every time a smack at the valves while cranking she would fire up. Do nothing trip a overcrank.

 

[Martin J]

I'd check the solenoid on the pump. Remember it actuates to open the fuel when the key is on. It;s not a stop solenoid. it's a opening solenoid for the fuel when the key is on. it's an easy check. Doodie 99 Has described as well.

 

[slowgoesit]

Verify your fuel selnoid is getting the right power or dropping out. Then id check for fuel at the injectors by cracking a fuel line while cranking. When were the fuel filters changed last? Did they start to let air in? Got a manual fuel prime pump?

He answered this in post # 5

 

[CharlieO.]

Is there any kind of linkage attached the fuel stop solenoid? If there is a linkage and its out of adjustment even the the known good part won't work.

 

[chriscritchett]

Loosen the fuel injector nuts holding the fuel lines. Then crank the motor a few rounds. There should be fuel coming out of each of the lines at the injectors.

This, if you haven’t yet. My fairly new-to-me Cummins 6BT died one day idling at the dock, refused to restart though it cranked fine. Fuel system had not been touched in months (i.e. no reason to suspect air).

Chased electrical connections for hours, verified the solenoid was clicking, new start battery just in case (was replacing them all with AGM anyway). And then I cracked the nuts out of desperation.

After a few revs the fuel started to spit out (jam paper towels around the loose connections to save yourself a big mess). Do it again. If it’s like mine it will start to fire once the air is out. Stop and tighten the nuts. Vroom.

Made no sense to my diagnostic self, but somehow some air got in there. Easy fix and great practice for next time. Good luck!

 

[High Wire]

If the lift pump died it will also crank and not fire. So mechanical or electrical lift pump?

 

[Osprey69]

Mechanic # 1 correctly diagnoses a bad diode in fuel shut-off solenoid power wire.

Owner orders and proceeds to install incorrectly. Apparently they are unidirectional.

So mechanic #2 comes aboard and was working with a baseline that was wrong. Only when he flips the solenoid AND wiring over from the port engine does she fire right up.

He assumed I replaced the power wire correctly. I guess he also assumed that I am not an idiot.

Thank you to all for responding to a simple problem that I made more complicated than need be.

 

[SteveK]

Mechanic # 1 correctly diagnoses a bad diode in fuel shut-off solenoid power wire.

Owner orders and proceeds to install incorrectly. Apparently they are unidirectional.

So mechanic #2 comes aboard and was working with a baseline that was wrong. Only when he flips the solenoid AND wiring over from the port engine does she fire right up.

He assumed I replaced the power wire correctly. I guess he also assumed that I am not an idiot.

Thank you to all for responding to a simple problem that I made more complicated than need be.

Thanks for closing post. Too bad this information was not included in post #1

 

[bowball]

I’m a bit confused. You said it ran fine at dock and then a week later no start. But you changed the solenoid in that time period? Wasn’t that the last action before it didn’t start?

I think the thread is informative and interesting can you give us your lessons learned?

 

[Osprey69]

This information and conclusion was not known until this morning. First post was on 2/23.