Cat 3208’s won’t start

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HaleTiki

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newport harbor
Two 1979 cat 3208’s won’t start. Read through all of osprey69’s thread. Both ran fine until one day both wouldn’t start. Has new filters, bled all injectors, start solenoids are operational, no water in fuel, fuel tanks full, batteries full, rotation strong. Again, both engines wouldn’t start exactly the same time, when prior day they started fine. Any geniuses out there?
 
Does the boat have a fire suppression system that is tied into shut down solenoids at the fuel injector pumps? I can't think of much else beyond what you have already ruled out.
 
Does the boat have a fire suppression system that is tied into shut down solenoids at the fuel injector pumps? I can't think of much else beyond what you have already ruled out.
Thx, but No fire tied into system, both solenoids work and fuel comes out of injectors when they’re cracked open and engine is turned over.
 
Are they 3208 N/As or T/As?
 
Are all fuel valves open? Is the return line open?

Advance throttle 25% then crank.
If no luck here I usually crack open the injector nuts, start cranking and then tighten the injector nuts one at a time.

There is only one possibility here. No fuel. If engine didn’t crank I would have other possibilities but not with a cranking engine.

Dual catastrophic failures on shut down is against all odds.
 
We had the same thing happen on our 3208NA's. The injectors needed to be cleaned and rebuilt. It was a coincidence which I still have a hard time believing but it has run perfect since.
 
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How cold is the engineroom? Is there a glow plug system?

If you have solid fuel coming out of the injector tubes when the injector nut is slacked then you have fuel. You could pull an injector an look for buildups on the tip.
But it could be the engines are colder than normal and don't reach ignition temperature while cranking. If the engines have block or pan heaters, turn them on for an hour or so before starting. Or using a hair dryer, point it into the intake while cranking. Or you could give the engine a whiff of starting fluid. Starting fluid is safe if you don't overload the engine.
 
I’m not meaning to insult, but it sounds like the boat is new to you, so a couple of ideas. Do you have a key and a seperate start button? Turn the key to energize and then push to start? The previous owner of my boat installed a security toggle switch on my boat that tapped into the start system of the boat. It was under the helm and easy to bump to the off position. Im skeptical this is the problem since your engine is turning over and you have fuel, but thought I would mention it.
 
We had the same thing happen on our 3208NA's. The injectors needed to be cleaned and rebuilt. It was a coincidence which I still have a hard time believing but it has run perfect since.
This is the only answer that I haven’t already ruled out. Can I remove the injectors myself? Or would you suggest I get one of the mechanics (who haven’t figured it out either) to do it? Is that a machine shop type job, or can I do it in my shop?
 
This is the only answer that I haven’t already ruled out. Can I remove the injectors myself? Or would you suggest I get one of the mechanics (who haven’t figured it out either) to do it? Is that a machine shop type job, or can I do it in my shop?
I had the same engines and thought about removing injectors for a general service at 3000 hours and 33 years of operation.
The word form our Cat guy was if they are running ok, just leave them alone, apparently they can be damaged by removal and expensive to replace.
 
This is the only answer that I haven’t already ruled out. Can I remove the injectors myself? Or would you suggest I get one of the mechanics (who haven’t figured it out either) to do it? Is that a machine shop type job, or can I do it in my shop?
While anything is possible, it seems very, very unlikely that both are running fine then suddenly neither engine starts. Rather than taking out the injectors, see if you can get a diesel mechanic to look at it. An hour or two of a mechanics time is probably lower cost and quicker than taking eight injectors to the shop.
 
This is the only answer that I haven’t already ruled out. Can I remove the injectors myself? Or would you suggest I get one of the mechanics (who haven’t figured it out either) to do it? Is that a machine shop type job, or can I do it in my shop?
Our mechanic removed them, took them home, cleaned and returned and replaced them a week later.
 
IMO, the problem's got to be fuel delivery. You'll get a little fuel out of a cracked open fuel line when cranking even if the engine is not getting enough fuel to run, it just won't have enough volume to open the injector. Take one of the fuel solenoids off the engine and manually operate the fuel stop valve. If that makes no difference, you'll need to trace the fuel line to see where the fuel is being blocked.
 
Both engines were running then the next day both engines won’t start. My first thought is fuel shut off solenoids (an electrical issue). My second thought is fuel valves (something got turned off).

It appears that OP has ruled out these possibilities. The odds of anything else effecting both engines at the same time is hard to imagine. I won’t say impossible.

Was fuel added to the boat right before shut down or are we mistaking water for fuel? Sucking water could shut both engines simultaneously but to do so just as you shut down are long odds.

Do keep us informed. I really feel for you. This is a most difficult diagnosis.
 
If it was one engine I'd disconnect the wiring to the stop solenoid to take that out or check for a short at the stop switch, I'd also check the wiring at the microswitch that prevents starting in gear. All of those issues I have had on my boat, but both work then don't work is a head scratcher.
 
Two different boats quit on me with the same problem. The kill switch return spring couldn't overcome thirty years of grime leaving me permanently off. A shot of WD 40 fixed it. But do both motors use the same kill switch? seems unlikely, what is the common denominator?
 
Is there an emergency air shutoff mechanism that could have been deployed by accident?
If they're warm enough, fueled, and cranking the only thing left is air..I think?
 
The OP seems to have left the chat. Has anybody else noticed more of these diesel engine questions now that boatdiesel.com is kaput?
 
The OP seems to have left the chat. Has anybody else noticed more of these diesel engine questions now that boatdiesel.com is kaput?
Yes. Definitely noticed. Boatdiesel.com was awesome.
 
The OP discounted the fire suppression system being in volved but I believe this could still be the issue. I had it happen. I needed new computer boards for it. Then later I had one of my generators overheat and blow off the exhaust hose and my Fireboy recognized smoke and killed all of my motors until I hit the disable switch in the fly bridge.
 
Two 1979 cat 3208’s won’t start. Read through all of osprey69’s thread. Both ran fine until one day both wouldn’t start. Has new filters, bled all injectors, start solenoids are operational, no water in fuel, fuel tanks full, batteries full, rotation strong. Again, both engines wouldn’t start exactly the same time, when prior day they started fine. Any geniuses out there?
Try loosening the injectors nozzles and see if the engine turns. If it turns, it is an injection problem, maybe your pump is having problems.
 
This may sound really silly, but the last time I had a couple of 3208s suddenly not want to start, the problem turned out to be low battery power. They were running just fine the day before, all day. But we moored with no easily accessible shore power, and the generator had quit the night before due to a fuel delivery issue. We finally borrowed a couple hundred feet of extension cords and plugged in the battery charger for a couple of hours. Boom, they started right up. Oddly, enough they both turned at what appeared adequate RPM which turned out to be just a tiny bit below the 250 RPM the mechanic we consulted said they required.
 
A diesel engine only stops due to lack of fuel. If you loosen the injectors, it becomes lighter for the battery and should turn over. Then, using the prime pump, tighten each nozzle and if there is fuel, it will start working again.
 
Same thing happened on our 3208 NA's. Unbelievably it was the injectors going sideways on both of them simotaneously. My mechanic pulled and rebuilt and no problems since.
 
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