No priming after filter change on M25XPA

[Project_Mayhem]

My new to me boat that had been on the hard for the last couple of years was launched today. We ran the engine last year when I bought it, then a few days ago, very briefly to verify alternator functionality. We changed all the filters and fluids yesterday (including separator and facet filter). Come launch day, we expected it to take a while to run but we couldn't get it running for more than 20 seconds.

The system is setup like this: Tank => Racor 200 series separator/filter (w/ manual prime & bleeder) => Engine Facet pump => spin on filter => Injector pump

I started disconnecting fuel lines to see where fuel was and wasn't. Residual fuel or no fuel came out of every line and fitting I checked even while applying 12v to the facet pump. We verified that the tank valve was opened, checked for pinched lines, cranked the motor quite a bit... As a test to verify that this was fuel supply issue I took a hand pump and connected it between the tank and the Racor. The bleeder valve on the Racor started spitting out fuel as pressure built. I closed it, kept pumping until I felt a reasonable amount of resistance and the engine started right up. I disconnected the hand pump and the issue returned. Lots of cranking with occasional combustion.

The only theory I have at this point is maybe when the boat was moved, sediment from the bottom of the tank was stirred up and clogged the filter on the pickup tube. The hand pump is probably far more powerful than the facet so it was able to overcome a potential clog? Seems plausible but unlikely. I'm stumped for now

 

[Ralph Johnstone]

sediment from the bottom of the tank was stirred up and clogged the filter on the pickup tube.

The last thing you want in the tank is a filter hanging off the inlet to the hose. If you have reason to believe there is one in there, it's gotta go.

 

[Stu Jackson]

Tank => Racor 200 series separator/filter (w/ manual prime & bleeder) => Engine Facet pump => spin on filter => Injector pump

Check for a screen on the pickup tube in the tank. Do you use the knurled knob to bleed? Should never have to use the hand pump on a filter housing with a fuel pump on M25 series engines.

Here's for M25 and M25XPs:

Bleeding 101 Bleeding M25 Series Engines 101- A Summary of Links for You

 

[Project_Mayhem]

I tried the knurled knob and nothing came out, even after I got it running with the hand pump. I've read several posts and guides, including yours, regarding bleeding. The issue is that it's simply not pulling much if any fuel. When I use the primer on top of the Racor, I will feel resistance after a few pumps. It's the same feeling you'd get if you put your finger over the end of a blunt syringe and try to push/pull the plunger. Unfortunately this system is new to me so I don't have much of a reference of what's normal.

Is it possible that a clogged Racor check ball could cause these symptoms? Or perhaps an incorrect re-assembly of the facet pump? My friend serviced it and will be checking on it today, starting from the tank and moving forward. I've advised him on the check ball and pickup tube filter

 

[jssailem]

checking on it today, starting from the tank and moving forward.

It is tedious but the best way to resolve fuel issues. Certainly the Racor check valve (discovered and reported here by @Stu Jackson) and a filter screen clog could be the fault. You may find the clog is from an accumulation of diesel fuel debris at one of the hose connection points. That is what happened to me. Fear not you’ll resolve this hiccup and be sailing soon.

 

[Tally Ho]

Any chance that the on-engine pump is bad? Sounds like it runs if you hand pump the fuel, but from the engine fuel pump.

Greg

 

[Project_Mayhem]

There's another thread with nearly this same issue on a C28. @JoeWhite stated that the pump must run for 60 seconds. I don't think we did it for more than 30.

Any chance that the on-engine pump is bad? Sounds like it runs if you hand pump the fuel, but from the engine fuel pump.

Greg

Are you referring to the electric or mechanical pump? Either way, I'm thinking it's unlikely as it ran fine under it's own power before we changed the filters. The engine hadn't been started since September or October and started up after 10 seconds of cranking. I believe I read on some models of the M25-XP, that the fuel pump gets shut off after oil pressure has built up. I guess Universal saved themselves $5 by not adding a fuel pump pressure cut off switch?

My friend said that he's going to pull the decompression valve while cranking to get the mechanical pump to spin faster.

 

[Tally Ho]

What ever you have… “facet” pump. I assume it is an electronic fuel pump (unlike the mechanical pump on my Yanmar). Can you hear it clicking when the key is on? Can you stick a hose in a can of diesel and connect directly to the fuel pump and see what happens?

 

[jssailem]

That will work.

 

[Project_Mayhem]

What ever you have… “facet” pump. I assume it is an electronic fuel pump (unlike the mechanical pump on my Yanmar). Can you hear it clicking when the key is on? Can you stick a hose in a can of diesel and connect directly to the fuel pump and see what happens?

I tried exactly what you described. Because the electric facet pump stops running after X time, I applied voltage directly to it with the output going into an empty water bottle. Little to no fuel came out. I don't think we ran it for more than 30 seconds. I'm ready to by pass the Racor as a test. This engine has two other filters and possibly a fourth on the pickup tube in the tank. There's notes in the manual about this filter in the manual from a PO but I'm not sure if it's been removed or not

 

[Project_Mayhem]

I just got word that the motor is running. The bleeder knob was opened and the the start button was held down for 30 or so seconds and it fired right up. We don't know why but perhaps gravity worked some fuel through the system overnight (tank is full) or the crap in the bottom of the tank settled back down?

 

[Stu Jackson]

I tried the knurled knob and nothing came out,

Nothing is supposed to come out...a frequent misunderstanding. Unless you have the downstream hose disconnected.

Is it possible that a clogged Racor check ball could cause these symptoms? Or perhaps an incorrect re-assembly of the facet pump? My friend serviced it and will be checking on it today, starting from the tank and moving forward. I've advised him on the check ball and pickup tube filter

Yes, of course it would be just that symptom.
Not much to the facet pump, just unscrew the bottom, filter and magnet inside.

 

[Stu Jackson]

Because the electric facet pump stops running after X time

It should keep running all the time the ignition switch is on.

This engine has two other filters and possibly a fourth on the pickup tube in the tank. There's notes in the manual about this filter in the manual from a PO but I'm not sure if it's been removed or not

The one in the tank is NOT a filter, it is a screen and has repeatedly been proven to end up being gunked up and solid, thus cutting off the fuel; everyone says it should be removed; 40 years of Catalina 34s and more years of C30s...

 

[Richard19068]

It should keep running all the time the ignition switch is on.

My Facet pump automatically shuts off when it has reached a certain pressure. In other words, if I turn the key to on but don't start the engine the pump runs for a short time and turns off after the fuel pressure builds up. It runs faster at first, slows down and then stops. I assume this is normal and means the pump is actually pumping fuel (at least until it builds up a set pressure).

 

[JoeWhite]

If the pump stops running as a result of fuel pressure, then there is no excess fuel return hose back to the fuel tank. So I was wrong in that assumption. On my M35B, this is how it is set up. If it is possible to have it setup this way for your engine. I highly recommend it as bleeding will not be needed. Bleeding is when you get rid of air trapped in the fuel hose which causes the engine not to start. By directing excess fuel back to the fuel tank it displaces all the air in the fuel hoses.

 

[odaydokay]

I assume that you undid the bottom of the Facet pump and took out the plastic screen and any other mom that is in there, removed the magnet disc also and cleaned that all up? I am assuming you have a Facet pump like mine, which is kind of shaped like a beer can only smaller.

 

[DaveJ]

My M25XPB may be different, but I think it’s the same. When I turn the key to the first position, the buzzer indicates that the oil pressure is low and the electric fuel pump does not run (no ticking). If I turn the key to the second position, the pump will tick, along with power to the glow plugs. This second position is how you bleed the line, but only do it for 10 seconds or so, let the glow plugs cool down. When you push the start button, the engine should build oil pressure, then the electric pump will come on. You won’t hear it, the engine is too loud. If you don’t have the buzzer in the first key position, you need to look into why, believe it or not it may be a faulty electric pump. Look into the archives for this, I’m on my phone and sailing right now, I could possibly help further tomorrow if needed.
Good luck.
cheers