Deere 4045 Fuel Lift Pump Not Priming

[scurvydog_pnw]

Well another week another project to look at.

So this is our second fuel filter change on our John Deere 4045 engines on our boat. Everything was pretty easy. Changed the secondary fuel filters on our Racors, changed the water filter and primary filter on our JD. The issue came when trying to prime the primary fuel pump when done.

The manual fuel lift pump as seen in the photos just would not bleed the air out of the system. I loosed the bolt circled in the pic on the water filter and cranked that puppy over a hundred times with the no luck. Could not even get bubbles to come out. We had to resort to cracking the nut on the primary fuel pump and cranking the engine over a dozen times or more to get the air out.

Now I have done this many times on our old Cats. with practically the same type of pump with no problem.

I remember having issues the last time not being able to prime the engines using the manual pump level as well. Once primed engines run without issue until next filter change.

We have multiple fuel tanks on the boat so the fuel level relative to the pump could be +/- 18". Fuel does go through a manifold system to a dedicated dual racor system for each engine as pictured.

Thoughts on why these pumps are not seeming to fill the primary fuel filter on the engine and then prime?

 

[STB]

How much air are you trying to bleed out?

If your primary fuel filters aren't full or nearly full, it can take a million or so years to bleed it by hand. You'll do better if you get them full or nearly full before starting.

If your fuel level is above the top of the primary (racor) filters, just loosen the top handle and let each one gravity fill then tighten up and clean up.

If the fuel level is below the top of the filter, fill them.as full as you can get them by hand. Use clean diesel, if you have it. I like to use seafoam, just because it comes in nice sized bottles. Some people use ATF and, it doesn't seem to have hurt anything, yet.

For a lot of reasons, you've got to make sure the 1ary fuel filters are closed snug and leak free at then top. Especially if you are trying to bleed out a lot of air so the fuel isn't helping to seal it, air can get sucked in there.

Ditto for the 2ndary fuel filter. Filling it up 1st makes life much easier.

And obviously triple check that the supply and return valves are open. (The return valve will be more important in getting the last of the air out of the system and actually starting than at this stage).

A clogged or restricted fuel tank vent will make it harder to bleed. You can try opening the fill to generate a temporary 2nd vent to see if that helps.

Also, if you didn't when cleaning, do drain some fuel from the bottom and make sure it is fuel. There is a slim chance there is water there and the float is shutting off flow within the filter.

Make sure the lift pump handle is going all the way up and down. Going to fast can sometimes reduce the stroke, making it really ineffective.

Also, on that motor /really/ loosen the bleed screw. Just a little bit and it might not vent much.

Also, it can sometimes take /hundreds/ of pumps by hand to prime the system. A couple hundred isn't unusual if there is a lot of air in it. This is why many people install electric bleeder oumps.

A lot of times one filter change will be a lot more work than the prior or next one. How much air you replace with fuel in advance makes a big difference as does the fuel level in the tank as compared to the top of the fuel filters, as does, at least for me, the temperature in the engine room and my own mood that day.

Ultimately, don't be discouraged. Especially if there is a lot of air, pump away.

 

[Comodave]

On our last boat I put Racor priming pumps into the 900MA filters. They weren’t cheap but they took up little space and worked great. I could use them to prime the Racors after the initial fill and also the secondaries. It would literally take about 5 seconds to prime the on engine secondaries on our Lehmans. It used to take about 75 pumps with the fuel lift pump. And they were very difficult to reach on the starboard engine.

 

[scurvydog_pnw]

Thanks for the in depth reply!!

How much air are you trying to bleed out?


If your fuel level is above the top of the primary (racor) filters, just loosen the top handle and let each one gravity fill then tighten up and clean up.

>>> Yup I would gravity fill these to the top.

If the fuel level is below the top of the filter, fill them.as full as you can get them by hand. Use clean diesel, if you have it. I like to use seafoam, just because it comes in nice sized bottles. Some people use ATF and, it doesn't seem to have hurt anything, yet.

For a lot of reasons, you've got to make sure the 1ary fuel filters are closed snug and leak free at then top. Especially if you are trying to bleed out a lot of air so the fuel isn't helping to seal it, air can get sucked in there.
>>> I will take some diesel and wet the filter seal first.

Ditto for the 2ndary fuel filter. Filling it up 1st makes life much easier.
>>> So this is the catch 22. I leave these empty as I don't have filtered diesel. So either I suck a lot of air out OR I fill these from the bottom of the racor after I drain out the bottom to make sure it's water free.

And obviously triple check that the supply and return valves are open. (The return valve will be more important in getting the last of the air out of the system and actually starting than at this stage).

A clogged or restricted fuel tank vent will make it harder to bleed. You can try opening the fill to generate a temporary 2nd vent to see if that helps.

Also, if you didn't when cleaning, do drain some fuel from the bottom and make sure it is fuel. There is a slim chance there is water there and the float is shutting off flow within the filter.

Make sure the lift pump handle is going all the way up and down. Going to fast can sometimes reduce the stroke, making it really ineffective.

Also, on that motor /really/ loosen the bleed screw. Just a little bit and it might not vent much.

Also, it can sometimes take /hundreds/ of pumps by hand to prime the system. A couple hundred isn't unusual if there is a lot of air in it. This is why many people install electric bleeder oumps.
>>> Yeah I think I did 200 and than stopped.

So question we have a fuel transfer pump what if I crank the air bleeder knob fairly open and close the egress mainfold so the pump is essentially pressurizing against the one engine. I am think like a bump on the switch to pressureize it. Would that be too much pressure going into the racor -> lift pump?

 

[scurvydog_pnw]

On our last boat I put Racor priming pumps into the 900MA filters.

I have the Racor 500 series (dual) I don't see anything anything on Parker's website for those models

 

[STB]

Thanks for the in depth reply!!



So question we have a fuel transfer pump what if I crank the air bleeder knob fairly open and close the egress mainfold so the pump is essentially pressurizing against the one engine. I am think like a bump on the switch to pressureize it. Would that be too much pressure going into the racor -> lift pump?

The transfer pump connects two tanks? The vent should stop a tank from building any pressure, preventing it from pushing fuel through the racor.

Also, although people do sometimes put priming or lift pumps between the tank and the racor, the racor's are really designed to operate under vacuum, not pressure. So, there are limits to how much of that one can do.

 

[STB]

I have the Racor 500 series (dual) I don't see anything anything on Parker's website for those models

I think the priming pump Comodave mentioned is only available for 900 and 1000 series, not 500 series.

Most people plumb a brand X pump in a shirt section of line parallel to the main fuel line and selectable by valves.

Mine is very low resistance, so I have it in my main line, but only turn it on to prime (or as an emergency backup to my lift pump).

 

[STB]

Also, you can pump a bunch by hand, use the starter for a short bit, then give the starter a rest to cool while pumping more by hand, and repeat until done. If it accidentally starts, you win. Tighten it up and it'll bleed itself.

Filling a filter by pumping the primer lever may well be necessary, but it can be a ton of work.

 

[Jeff F]

Thanks for the in depth reply!!



So question we have a fuel transfer pump what if I crank the air bleeder knob fairly open and close the egress mainfold so the pump is essentially pressurizing against the one engine. I am think like a bump on the switch to pressureize it. Would that be too much pressure going into the racor -> lift pump?

I have the same engine and filter assembly. I haven't had to do it, but won't hesitate to use the transfer pump for priming if I need to. The transfer pump shouldn't be blowing up fuel systems if a valve is closed.

 

[Transaxial]

When changing filters it is never a good idea to use unfiltered fuel to help with the priming process. I installed a selector valve on the output line of my home made polishing filter system that uses the polishing pump and filters to pressure bleed the engine filters. I needed a shut off valve in the engine supply line so that fuel flow from the polishing system couldn’t just back flow to the tank. This kills two birds with one stone. Fills all empty filters with fuel filtered to 5 microns. This is very important on modern electronic high pressure common rail engines.

Is the reason your manual primer will not work because the fuel had run back to the tank when the filters were open leaving that pump in an air lock situation ? Maybe a shut off valve in a convenient location anywhere between the manual pump and the tank would keep that line and pump full of fuel for after a filter change??? As suggested a $100 electric pump that free flows when not running and installed down low in the supply line, so it gravity feeds from the tank, could save you a lot of trouble and accomplishes the supply of filtered fuel to fill the filters and engine pump. There is just too much air in the fuel system for the engine to start unless you can effectively bleed most of it out so a tiny bit in a high spot will just pass through the return line to the tank. Some of the new hpcr systems are tricky.

 

[twistedtree]

Mechanical pumps like yours are drive off a cam in the engine. The cam levers the pump, just like the little hand lever. If the engine happens to stop with the cam in the up position, then you hand pumping will do nothing because the pump is already stopped at the top of it's stroke. You can usually feel this because there is no resistance in the hand lever.


Try bumping the engine with the starter to turn it and hope it stops in a different position. Then try again and see if you start to feel some resistance in the lever.

 

[SailorGreg]

Mechanical pumps like yours are drive off a cam in the engine. The cam levers the pump, just like the little hand lever. If the engine happens to stop with the cam in the up position, then you hand pumping will do nothing because the pump is already stopped at the top of it's stroke. You can usually feel this because there is no resistance in the hand lever.


Try bumping the engine with the starter to turn it and hope it stops in a different position. Then try again and see if you start to feel some resistance in the lever.

Hi, you didn’t mention which model 4045 you have. Some models have an electric fuel pump, some don’t. Mine are 4045 TFM85 s. No electric pump. But still the manual instructs to turn on the ignition as part of the sequence. Are you doing that?
As someone mentioned, the manual pump takes more effort than expected to make a full throw.
I think you mentioned you filled the filters first. If not, it takes forever to bleed.
I mention all this because it only takes me a few strokes to bleed, so hopefully we can find a simple solution. Good luck.

 

[twistedtree]

Hi, you didn’t mention which model 4045 you have. Some models have an electric fuel pump, some don’t. Mine are 4045 TFM85 s. No electric pump. But still the manual instructs to turn on the ignition as part of the sequence. Are you doing that?
As someone mentioned, the manual pump takes more effort than expected to make a full throw.
I think you mentioned you filled the filters first. If not, it takes forever to bleed.
I mention all this because it only takes me a few strokes to bleed, so hopefully we can find a simple solution. Good luck.

I have had both versions. My current 4045AFM85 has an electric pump and although I haven't changed fuel filters yet, I think (hope) is will self bleed with the electric pump.


Previously I had a 4045DFM75 (I think), but I'm pretty sure that had an electric pump too. Can't recall for certain.


Where I have definitely had mechanical pumps is on generators and the manual pump only works if you are on the flat of the cam. If you get unlucky and the engine stopped turning on the top of the lobe, you can stroke the lever all you want, but nothing happens. That's what I'm wondering might be happening with this 4045 that's in question.

 

[sunchaser]

It is a good idea to close through hulls when excessively cranking to avoid filling the exhaust system with raw water

 

[twistedtree]

It is a good idea to close through hulls when excessively cranking to avoid filling the exhaust system with raw water

Yes, important point

 

[Jeff F]

I agree that the cam position matters for the manual pump. I learned that with my Cummins, which is essentially identical.

Coincidentally, I ran one of my tanks dry yesterday with my TFM75. There is no electric fuel pump on mine. I didn't have any problems bleeding all the filters with my full fuel tank above the engine, and it was straightforward from there.

The lift pump is between the two on-engine filters. I guess they call the first a separator and the second a filter. It's likely not going to work if there's air in the first unit.

Tangentally, I had a brief period of anxiety recently when blasting (for me) down the St Lawrence River. I was peeking at the fuel separator and noticed a stream of bubbles going through. Switched filters, then tanks, and it continued at high rpm. It turned out to be the supply line for my furnace which I had added to the intake fuel manifold last fall. Air was being sucked in there somewhere. Easy to isolate.

I was surprised that the only indication of issues came from my casual observation. I guess the system can deal with some small amount of air being introduced.

 

[scurvydog_pnw]

Hi folks,
Work has been crazy so got time to catch up on the great feedback. Few items asked earlier in the thread.
1. Engine model is 4045TFM75
2. Lift pump is manual
3. When servicing the secondary racor fuel filters, if I crack open the valve the static pressure in the fuel tanks will fill the racor.
4. I don't specifically remember when servicing the on engine filters if I then re-closed the racor valve. However, that is a good idea as at least I won't have fuel flue back down the supply line from the engine to the racor.
5. We have two fuel manifolds on our boat. One which controls sources and a separate manifold which controls destinations.
6. Our fuel transfer pump is connected to both manifolds

I think my plan of action given the above information is for our fuel filter changes next year is that after I replace the primary fuel filter on the engine and the water separator filter to adjust the destination manifold and close off all 4 of our fuel tanks leaving the engines and generator the only option for fuel to flow. Open the air bleeding valve way up as per previous suggestion on the water separator assembly and then bump the fuel transfer pump. It should act as an inline pump at that point and pressurize the line to the engine forcing air out.

Sadly it will be about 10 months before I test this out

 

[guy with a boat]

Scurvydog, I just saw this thread for the first time but I do have this engine and had trouble bleeding it the first time I did the fuel filter change, so will add/reinforce some comments based upon my experience.

The procedure described in the manual of using the bleed screw and the hand pump works well and there is no need to improvise if this is done correctly. You got two important pieces of info earlier in the thread that you should pay special attention to:
1. Make sure you are moving the pump lever through its full travel. Don’t force it, but push it firmly until you are sure you know the full swing of the lever. It’s full travel is longer than it at first appears.
2. Read the earlier explanation of the cam and bump the starter if you aren’t getting results.

The hand pump and bleed procedure are effective and relatively fast once you get the hang of it. You will get solid fuel out of the bleed screw and then the engine will fire up easily. If both these things don’t happen, go back and read 1 and 2 above.

Trying to get the air out some other way risks other complications and unnecessary problems.

By the way, the secondary fuel filter is the one on the engine and should’nt have fuel added to it before installation because that bypasses the last filter and risks injector contamination.

Good luck.

 

[ronobrien]

Well another week another project to look at.

So this is our second fuel filter change on our John Deere 4045 engines on our boat. Everything was pretty easy. Changed the secondary fuel filters on our Racors, changed the water filter and primary filter on our JD. The issue came when trying to prime the primary fuel pump when done.

The manual fuel lift pump as seen in the photos just would not bleed the air out of the system. I loosed the bolt circled in the pic on the water filter and cranked that puppy over a hundred times with the no luck. Could not even get bubbles to come out. We had to resort to cracking the nut on the primary fuel pump and cranking the engine over a dozen times or more to get the air out.

Now I have done this many times on our old Cats. with practically the same type of pump with no problem.

I remember having issues the last time not being able to prime the engines using the manual pump level as well. Once primed engines run without issue until next filter change.

We have multiple fuel tanks on the boat so the fuel level relative to the pump could be +/- 18". Fuel does go through a manifold system to a dedicated dual racor system for each engine as pictured.

Thoughts on why these pumps are not seeming to fill the primary fuel filter on the engine and then prime?

Someone else may have eluded to this, but in the odd chance that the engine stops with the FP actuator lobe on the cam in the "high" position the hand primer will be ineffective. Try the primer again and see if it works, if not try rotation the engine by hand about 180 deg and try again. If still no work, you have another problem.

 

[scurvydog_pnw]

Thanks for all the great suggestions folks. Will see how things go with next years filter change.