Strange Power Loss - Weterbeke 27
There is NO third fuel filter into the lift pump as is indicated with the Westerbeke 27 manual. The "stock" lift pump has been replaced by one without a fuel filter. (Not too pleased about this...)
Fuel Tank is approx 5 yrs old.
Changed Filters Primary and Secondary 3 Weeks ago
Ran for approx. 50 hours trouble free before the first problem (see below)
Crossed Albemarle Sound in 25-30 kts dead into wind. Perfomed perfectly.
Status of Fuel in tank before December is unknown (just bought the boat). (I now know I should have polished fuel system before setting out but I didn't...)
2 days ago - the first indication of a problem
Sailing up Chesapeake in 15 - 20 needed to drop sail and start engine (for another unrelated reason).
Had already been run for approx 35 hours trouble free on this trip.
Ran fine for 1 hour - seas 3-4ft.
Engine died... lost power then died completely
Changed Primary and Secondary filter.
Attempted to bleed air out at injectors. (I wasn't sure if I did it correctly)
Restarted - It took approx 10 restarts to get it running. Ran rough and would every 10-15min lose 200 rpm then "slowly" creep back up to "set level". (Approx 2100 rpm)
We headed in to Marina. The last 2 hours of the trip the engine ran perfectly. (Calm seas near the shore at that time)
We filled up at the Marina and ran it for 90min at the dock. (in forward at 2000 rpm). It ran perfectly.
At that time we drained the water separator (looked good, maybe 1 or 2 drops of water)
We disconnected the input to the primary filter and blew air in the hose to ensure 2 things. 1) That the tank vents weren't clogged. 2) That the line itself wasn't clogged. The line blew free and clear... Made nice bubbles in the tank.
Headed out at dawn the next day.. Ran perfectly for 5 hours. When the seas started picking up it lost 200 rpm and creeped back up to setting again. It did this 4 times. (again we were at just under 3/4 tank).
We did two things. 1) topped off the tank with diesel. 2) blew again on input hose to fuel tank to make sure no clogs and clear vent.
Started engine it ran well for 1 hour then lost 200 rpm and creeped back up to set level. It did this 3-4 times. Seas were 2-3 feet with the occasional 4 ft.
(see yesterday's wind at about 4pm)
NDBC - Station COVM2
We had too much wind on the nose and headed into a Marina (on the Patuxtent).
Winds too high to leave now and we wondering what our next step could be.
Change primary and secondary again.
According to Westerbeke manuals these engines don't need to be "bled". I'm really not sure if I buy that. Thoughts?
Run at the dock for a while to see if the air is out of the fuel lines.
Option we are discussing:
Take the fuel line off the inlet to the primary and plum it directly into a spare diesel tank with known good fuel / clean tank. Thoughts?
Is it typical, in high seas to have this symptom of 200 rpm power loss?
Is it typical, after filter changes to have this symptom of 200 rpm power loss?
If a lift pump is not operational, is it possible to have enough "weight" of fuel to provide diesel to the injector pump?
If a filter is clogged, isn't that independant of seas/wave height? Won't the flow just "stop"?
I appreciate any insight, or ideas you may have.
One possibility is that in the rougher seas, crud is breaking loose inside the tank. Not sufficient to completely clog the filter, but enough to slow the outflow from filter to engine, thus causing the drop in rpm.
I've never had a filter just clog at one moment. It seems to come on slowly, signified by a gradual loss of rpm, until it finally stops sending fuel.
Craig I'm asuming that you have an electric fuel pump? This could very well be the problem.
Thanks PB... These are the experiences that I'm looking for.
Greatly appreciate it.
My experience with these engines is limited.
Have you had one fail? What were the symptoms? As i described? Elec fuel pump sounds like something that would just... die.
I strongly suspect that your problem is that there is a screen on the end of the pickup line in the tank. This was (is?) standard for Sabres. When crud breaks loose, it gets sucked against the screen and inhibits fuel flow and results in significantly reduced power (also manifests itself as surging power).
We removed the screen on both our Sabres (28 & 38) and the problem went away. Both engines exhibited symptoms like yours. On the 38, after removal, we sucked so much crud into the Raycor, that it was like jello when I pulled the filter several months later. The filter has been clean ever since. The rationale is that you have 3 filters and it's far easier to replace them than to clean the screen. I'm not sure how your screen is installed - it may be at the end of the pickup in the tank (as in our 28) or it could be at the top of the pickup at the top of the tank (as in our 38). Either way, it's somewhere in the tank, unless the PO removed it (doubtful). Yank the screen and your problem should go away.
You should have 3 filters on your Sabre - a Raycor (#1), a lift pump (#2), and a final (#3). The last 2 should be monted on the engine itself.
My guess is that you have a leak somewhere in the fuel line, and it's probably on the suction side which is why you are having trouble finding it. Check all aspects of your primary filter setup and all your hoses and fittings from the tank up through the last pump you have in the line (if you have a mechanical lift pump, that's probably the last in the line, even if you also have an electric pump). For instance, some of the Racor primary filter setups have a plastic screw cap at the top of the assembly. If that cap has a slight crack, you could be sucking air right there. Not enough to bother you with normal operation, but when you get on the thing or it's working harder because of conditions, that might be enough to make it buck. (Take a guess as to how I know this.) Same could be true with a loose connection with a hose clamp, or a pinhole in a fuel line on the suction side (not likely to be on the pressure side because you would be spitting diesel out of the hole and it would be easy to find).
My guess (and obviously that's all it is) is that it's not the fuel. You've refueled a few times, and if it was fuel you'd have the problem regardless of conditions (save for the possibility of churning up junk from the tank, but you'd know if that was the problem when you changed the filters; they'd be clogged with all kinds of nasty stuff).
Another possibility, but I bet this isn't it, is that you might have a screen on the bottom of your pickup tube to the fuel tank. When you're banging around in seas, the junk gets sucked up and clogs the screen. When things settle down the junk falls off the screen and you have better fuel flow. It should be easy to check. Just unsrew your fitting on the tank to which your fuel line is connected and pull it out of the tank (the pick up tube should be connected to the fitting and just lift out). Take a look at the bottom and see if there's a screen. Also, doing this will give you a sense of whether you have algae in the fuel, as the pickup tube itself will have slime on it.
Generally speaking, fuel system problems are easy to find, with one exception, and that's a leak on the suction side. So, if you've tried a bunch of things and can't find it, I'd look hard at every component on the suction side. If you have one, a vacuum gauge ought to tell you if that's your problem too.
Another thought, which hopefully won't be the situation, is that you have bad compression in one of your cylinders. Hard starting and rough running often is a sign of that. That could be caused by a bent rod or a variety of other things. You should hope it's not that, as that will be a more involved (and expensive) process to fix.
All that said, I don't have experience with Westerbeke engines, so it also could be something anomalous to them, in which case ignore all of the above. :D
Keep us updated. I'm curious to know the conclusion.
Rereading your post, I see that you're questioning the self bleeding feature. It's true, I haven't had to bleed a line, EVER on any of my Westerbekes. i really think that your problem is the screen. If none exists, then I'd investigate the other, more complex reasons. But this really sounds like fuel starvation. Been there, felt that!
My W 30b does if fact self bleed. I had similar problems to you when I got my boat (and new engine) last year - the problem was the electric fuel pump had a loose connection.
The pump puts out 25 gallons a hour and you are using about 3/4 of a gallon of that, the rest gets recycled thru the tank and filters again. You are in fact polishing your fuel every couple of hours you run your engine - if the pump is running full time as designed. Finding the problem is difficult because as long as it runs every couple minutes you have enough pressure and fuel to run. It's when it goes a while that life sucks.
Check the 12v connection, tighten clean etc..then check the pump. If your really want to get fancy wire a light to the pump side of the connection and put it somewhere you can see it while the engine is running. Then you'll know if it's intermittent. Intermittent problems suck to find.
Eliminate the tank and pickup tube issue by getting a 5 gallon can of diesel and hose then feed the engine directly from there as a test, with the unused fuel going back to the same 5 gallon can (see below).
Troubleshooting possible multiple issues is simpler if you can eliminate one piece at a time.
It might be a air leak - easy way to check for that is to take off the hose that sends unused fuel back to the tank and put it into a bucket, run the engine and see if you have bubbles in that bucket (pre-fill the bucket with some fuel and put the hose under the fuel so you are not making bubbles with flow).
Westy's are good engines, but the electric pumps are somewhat exposed and prone to getting the connections knocked around while doing maintenance. The bad news is a replacement is 158 bucks (I've got two spares, I'll be glad to give you a discount). The good news is - almost any 12v fuel pump from autozone will do the same job for 40 bucks - damn, just killed my own sale.
Thanks alot for your insight.
I have the Raycor and the final. There have been mods on the lift pump. It has a different version than the one that came stock. NO FILTER.. hmmm
Will investigate further.
Again... thanks so much for sharing.
|All times are GMT -4. The time now is 01:34 AM.|
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012