Perkins 4-108 Power Loss and Shutdown

[RJ86]

Well, I'd like to say that I solved the mystery and got the engine running; I did get the engine running, though, finally, using starting fluid. The engine runs just fine, but the mystery remains. I didn't actually fix anything. I just fiddled around with stuff, and about the time I was ready to tackle the injection pump, the engine finally started, on about the 500th attempt. I don't have an explanation, but I do have a couple of observations.

I had switched the racor to the 30 micron filter right after the engine died, just in case, but switching back to the 2 micron filter after the engine was finally running again didn't cause any power loss, and there was negligible pressure on the vacume guage. I then changed the 2 micron filter just for the heck of it, and noticed that only the lower half of the element looked dirty. Apparently this is fairly commonplace, and it seems that the fuel level, even after topping the filter off after changing it, tends to 'settle' to an inch or so below the top of the filter after a while. I've heard that topping the filter off with fuel again after running the engine for a while is a good idea following a filter change. I'll give that a try

I also changed the secondary filter (Baldwin, 10 micron) while I was troubleshooting, although it's hard to see how this one could have been clogged with the 2 micron Racor filter upstream. Moreover, the abrupt nature of the power loss and shutdown (it quit as if I had pulled the engine shutoff cable, and I was motoring along at around 3000 rpm, with half a tank of diesel remaining) didn't seem to me to be typical of the gradual power loss associated with dirty fuel filters. Anyway, it still wouldn't start after changing this filter and bleeding the system, until days later, when it finally started with the spray. During all of the troubleshooting, and again after changing the secondary filter, bleeding the fuel system produced apparently clear fuel all the way to the injectors.

Perhaps it was just a glob of junk from the fuel tank momentary clogging the line. I did attempt to clear the fuel line by blowing 'backwards' into the line from the engine compartment to the tank, but there was no significant resistance. Moreover, we had run the engine about 100 hours or so recently, bashing our way up from Mexico, and had thus put about 100 gallons of fuel throught the tank, so a lot of sediment in the tank after all that seems unlikely. But I'm sure glad the thing didn't quit 2 weeks earlier, off Point Conception. Yikes!

Anyway, as you can see, I really have no friggin' clue what happened, but the thing is running great now, and I'd like to thank everyone for all of the excellent advice and suggestions.

Thanks again-
RJ

[Unicorn Dreams]

Didn't read all the post above, but you can check this out. Pull the floor board up over the tank and remove the fuel supply line from the tank, then remove the p/u tube and see if the screen is dirty or if the tube is cracked.

If that is okay, get a low pressure air gauge at the end of the line at the tank, pressurize, and see if it holds pressure, if not you have a leak. GOOD LUCK

Replaced all my lines on my 1976 Gulfstar. Had an illusive leak and decided to take the easy way out and replace them all.

[SkiprJohn]

Congratulations! I think the bashing through the seas from Mexico dislodged some gunk in the bottom of your tank and put a bit of clog in your lines.
Hope you don't have the same problem again. Like I said. It happened to me when I sucked a tank dry and the junk in the bottom of the tank got sucked up into the filters. That was at the end of a 2500 mile sail from Hawaii and in the ferry lane to Bremerton. Took me 45 minutes to diagnose the the problem, change the filters and bleed the system to get the engine running again. 45 minutes ghosting along under sail in the ferry lane does put some pressure on you.
kind regards,

[Lufthund]

OMG !
This is exactly what just happened to me
4108
And just south of half moon bay.
I did a 180 and sailed to Santa Cruz where I sit trying to figure this nightmare out.
My Raycor definitely had sludge in it but I’ve stripped it down and cleaned it
New filters all round
Bypassed fuel tank with fresh fuel
Bled system again and again
It just won’t start

[donradcliffe]

Where are you in Santa Cruz? I've got a few spare hours this morning. Text me at 831-332-1272.

[Lepke]

If your primary filter is below the level in the fuel tank, you can slack the handle on a Racor and the fuel will purge any air in the top.
If the dirty fuel filter looks black, you have organisms in the tank and it needs a dose of biocide.
I use 2 micron filters for my Detroits and after 500 hours look nearly new. Haven't replaced an injector since rebuild 10 years ago.

[Lufthund]

Thanks for everybody that reached out to me
I got a running and I think the issue may well have been the lift pump which thank goodness I had a spare of
With the rough seas the filters were definitely also an issue
Bleeding this old girl certainly was an experience
I’ll be leaving Santa Cruz at 3 AM hoping to make the Golden Gate tomorrow if the wind helps

[Lufthund]

Well it’s 3 AM and I was trying to leave Santa Cruz engine started first Time no problem shut it down did all my stuff went to start it a second time and it won’t start
I’m ready to jump off the bow headfirst
Strange I can get the engine to run when I open the governor bleed air screw as soon as I turn it back in the engine quits

[LittleWing77]

Originally Posted by RJ86

I had switched the Racor to the 30 micron filter right after the engine died, just in case, but switching back to the 2 micron filter after the engine was finally running again didn't cause any power loss, and there was negligible pressure on the vacuum gauge. I then changed the 2 micron filter just for the heck of it, and noticed that only the lower half of the element looked dirty. Apparently this is fairly commonplace, and it seems that the fuel level, even after topping the filter off after changing it, tends to 'settle' to an inch or so below the top of the filter after a while. I've heard that topping the filter off with fuel again after running the engine for a while is a good idea following a filter change. I'll give that a try.

I also changed the secondary filter (Baldwin, 10 micron) while I was troubleshooting, although it's hard to see how this one could have been clogged with the 2 micron Racor filter upstream. Moreover, the abrupt nature of the power loss and shutdown (it quit as if I had pulled the engine shutoff cable, and I was motoring along at around 3000 rpm, with half a tank of diesel remaining) didn't seem to me to be typical of the gradual power loss associated with dirty fuel filters.

Is anybody else wondering about the 30 micron Racor on the primary filter?

I was always taught that switching to something so fine (30 micron), especially in contrast to - what I assume is - the recommended 2-micron primary filter would create a profound restriction on the movement of fuel through the system. Anyone...?

Thanks,
LittleWing77

[Rubicon King]

Sorry for your plight. IMHO, I think the 3000 RPM is quite high for constant motoring for a 4.108. I have an M model on my 85 gulfstar Hirsch and I rarely run her past 2200 RPM. I cruise between 1800-2000 and sip about .75 an hour. no issues other than a self induced impeller meltdown when I left the seacock closed on time.

I would suspect a fuel starvation of some sort, or air in the line.

Best of luck

Originally Posted by RJ86

Hello all-

I was motoring upwind South of Half Moon Bay at about 3000 rpm last week when the engine in my 1979 Gulfstar sailboat surged briefly, and then shut down completely, almost as if someone had pulled the shutdown lever. I remember saying something like "Oh, darn," because with the wind against us, and forecast to die off at sunset, we definitely needed the engine to get to San Francico that night.

I checked all of the obvious things: fuel quantity, the filters (Racor primary and Baldwin secondary), and everything seemed normal. I then engaged an electric 'bleeding' pump that was added on to the fuel system, in case the mechanical lift pump had failed, but that didn't help.

Right now, I'm looking at the injection pump thinking.... "Gosh, THAT looks like fun! And I'm sure it'll be inexpensive, too!" So I was hoping for any ideas that might save me unnecessary work and expense.


Thanks in advance-
Rick

[Lufthund]

Update:
Sailed it into HMB @ 10:30 at night
What a day!
Zero wind to 35knt gust fronts
Fuel starvation is definitely not the issue. When opening the bleed screw diesel pours out under pressure
Tad are sending me a new anti stall device and I think I’ll get the pump looked at.
I’m a tenacious bugger and I’m not giving up lol