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Discussion Starter #1
I am pretty good with motorcycle and car engines. I have a 2001 K1200LT engine mounted in a 3 wheeled vehicle (google Trimagnum).Has done pretty good for almost 6 years but do not drive it much. Early this year, I was stranded a few miles from home and had to get it towed. Problem was the fuel pump quit. I removed the fuel tank and pump and installed an aftermarket fuel pump. Engine started, ran it around the block several times and then parked it for 3 months.

Went out to drive it 3 or 4 weeks ago and it would not start. Cranks but does not fire at all.

Here is what I have done the last 3 weekends.
1. I can hear the fuel pump noise when I turn on the key, checked hoses to be sure no leaks. Double checked routing of the fuel and return lines.
2. Pulled a spark plug and can see and smell fuel on tip. Spark plug gap and condition look good
3. Clamped spark plug to body ground and tried to start the engine. Can see the plug sparking from the electrodes to the center post. I also noted that my electronic (pickup on one spark plug wire) tachometer registers a few hundred RPM during cranking.
4. Removed and cleaned the air filter. It was pretty clean but took a vacuum to it anyway
5. drained out all the fuel and put 3 gallons of new fuel in the tank.

Note that I have done steps 1 thru 3 TWICE on separate weekends.

Any NEW ideas or similar experiences??

Tim
Tucson, AZ
 

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Possible clogged fuel filter, fuel lines connected properly or blown fuse. Just three things that come to mind when I was having issues. Good luck!
 

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You said you checked the fuel lines. Were these the ones inside the tank you checked? It is possible one of those has popped off or ruptured causing no fuel pressure. You have already ascertained spark so fuel is next. Possible fuel pump failure. Some of the aftermarket pumps are not so good. If you have the equipment, you can check for fuel pressure. Should be around 50PSI. As Snape said, clogged fuel filter is a possibility if you got any water in the tank.
 

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I am pretty good with motorcycle and car engines. I have a 2001 K1200LT engine mounted in a 3 wheeled vehicle (google Trimagnum).Has done pretty good for almost 6 years but do not drive it much. Early this year, I was stranded a few miles from home and had to get it towed. Problem was the fuel pump quit. I removed the fuel tank and pump and installed an aftermarket fuel pump. Engine started, ran it around the block several times and then parked it for 3 months.

Went out to drive it 3 or 4 weeks ago and it would not start. Cranks but does not fire at all.
I
Here is what I have done the last 3 weekends.
1. I can hear the fuel pump noise when I turn on the key, checked hoses to be sure no leaks. Double checked routing of the fuel and return lines.
2. Pulled a spark plug and can see and smell fuel on tip. Spark plug gap and condition look good
3. Clamped spark plug to body ground and tried to start the engine. Can see the plug sparking from the electrodes to the center post. I also noted that my electronic (pickup on one spark plug wire) tachometer registers a few hundred RPM during cranking.
4. Removed and cleaned the air filter. It was pretty clean but took a vacuum to it anyway
5. drained out all the fuel and put 3 gallons of new fuel in the tank.

Note that I have done steps 1 thru 3 TWICE on separate weekends.

Any NEW ideas or similar experiences??

Tim
Tucson, AZ
I can't tell from the web site: is the stock LT fuel tank used? If it is, are you absolutely sure the fuel lines reconnected correctly? I know you said you checked.. I have my QDs reversed so that I can only connect them correctly.

Are you sure the aftermarket pump has the same pressure capability as the original?

You have checked the obvious ignition related switches such as kill switch, kickstand switch, etc.?
 

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Discussion Starter #5
Here is Kemso fuel pump I installed.
KEMSO High Performance Fuel Pump for BMW K1200GT / K1200 / K1200LT 2004-2008
Kemso High Performance Fuel Pump for BMW K1200GT K1200 K1200LT 2004 2008 | eBay

I have a shop manual for my motorcycle and doublechecked that the lines wer installed correctly.

I guess I will have to get a pressure gauge to check the pressure.

No electrical disconnects because they were all removed when I stripped the motorcycle to build the 3 wheeled vehicle.

Have several fuses in the system but have checked all of them. When one blows, no cranking or electrical power.

The fuel tank is stock.

Tim
 

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Here is Kemso fuel pump I installed.
KEMSO High Performance Fuel Pump for BMW K1200GT / K1200 / K1200LT 2004-2008
Kemso High Performance Fuel Pump for BMW K1200GT K1200 K1200LT 2004 2008 | eBay

I have a shop manual for my motorcycle and doublechecked that the lines wer installed correctly.

I guess I will have to get a pressure gauge to check the pressure.

No electrical disconnects because they were all removed when I stripped the motorcycle to build the 3 wheeled vehicle.

Have several fuses in the system but have checked all of them. When one blows, no cranking or electrical power.

The fuel tank is stock.

Tim
If the tank is stock, open the tank and look in while you turn the ignition on and let the pump prime. If you see a large disturbance in the tank, then one of the two hoses has either burst from Ethanol exposure or has popped off. A slight movement of fuel is normal as the return line from the regulator on the fuel rail returns fuel to the bottom of the tank. A split or popped off in-tank line will be much more obvious.

As for the replacement pump, that is probably the least expensive one I have seen but no telling about its quality. It could have just crapped out so if no violent action inside the tank, a pressure test as you said is what you need to do next to ascertain the status of the pump, filter and regulator.
 

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Here is Kemso fuel pump I installed.
KEMSO High Performance Fuel Pump for BMW K1200GT / K1200 / K1200LT 2004-2008
Kemso High Performance Fuel Pump for BMW K1200GT K1200 K1200LT 2004 2008 | eBay

I have a shop manual for my motorcycle and doublechecked that the lines wer installed correctly.

I guess I will have to get a pressure gauge to check the pressure.

No electrical disconnects because they were all removed when I stripped the motorcycle to build the 3 wheeled vehicle.

Have several fuses in the system but have checked all of them. When one blows, no cranking or electrical power.

The fuel tank is stock.

Tim
I don't have my manuals handy, but I was thinking that the LT fuel pressure spec was 50 psi. This pump says it has higher flow at 43 psi than the stock pump, but doesn't say if 43 is the max pressure it can provide. I agree with you that a pressure check seems like a good next step.

This pump may be a screaming bargain, but it may also fall into the category of "if it seems too good to be true..."
 

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I don't have my manuals handy, but I was thinking that the LT fuel pressure spec was 50 psi. This pump says it has higher flow at 43 psi than the stock pump, but doesn't say if 43 is the max pressure it can provide. I agree with you that a pressure check seems like a good next step.

This pump may be a screaming bargain, but it may also fall into the category of "if it seems too good to be true..."
I agree with you on the possibly too good to be true. I don't think I would go for the stealer pump at $400 + but I probably wouldn't buy the least expensive either. It may be just fine but there is also some credence to the phrase, " You get what you pay for" . It is that inexpensive for a reason just as the stealer pump is $400 for a reason but that reason doesn't necessarily have anything to do with it actually being worth that much. It needs to be tested for sure unless the tank has a fountain inside it. .
 

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2005 K1200LT
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Since the fuel pump was the last thing touched I would pull it out again and check all hoses. Many here have installed new filters and hoses and the bike ran fine until it suddenly quit. It is almost always a hose has popped off. But i would also be wary of the $29 pump as it does not look anything like the $60 pump I bought as a backup unit.

Also check out this review (not you PN but the same MFG)
 
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I don't have my manuals handy, but I was thinking that the LT fuel pressure spec was 50 psi. This pump says it has higher flow at 43 psi than the stock pump, but doesn't say if 43 is the max pressure it can provide. I agree with you that a pressure check seems like a good next step.

This pump may be a screaming bargain, but it may also fall into the category of "if it seems too good to be true..."
As you said the fuel system MINIMUM pressure is 50 PSI (as specs in BMW shop manual or CLYMER). Because the CONSTANT 50 PSI is in fact controlled by the mechanical pressure regulator (at end of fuel rail), a correct specs fuel-pump needs to be able to supply a bit more than 50 PSI to keep system happy. Number of liters per minutes is also specs BUT not very critical in general as most of these pump can supply a lot more in normal running conditions.

In addition, you need to test all these conditions with a fuel pressure gauge installed in-line (on pressure side hose between tank and fuel rail)
(1) fuel pressure after 2 seconds prime following ignition ON should be close to 50 PSI (do not start engine yet)

(2) wait 30 seconds at least after ignition ON to see if pressure stays the same (should not drop more than a few PSI)

(3) start engine and watch for good constant pressure (50 to 54 would be OK)

(4) re-test after a while to see if fuel-pump (or regulator) does not act up with a hot engine after a long ride.

(5) Keep gauge plugged in-line, after engine is stopped and bike is parked for 10 minutes: recheck if pressure has not dropped much compare your running pressure (system should not loose much pressure - otherwise pump internal valve or injectors leaking).
 

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As you said the fuel system MINIMUM pressure is 50 PSI (as specs in BMW shop manual or CLYMER). Because the CONSTANT 50 PSI is in fact controlled by the mechanical pressure regulator (at end of fuel rail), a correct specs fuel-pump needs to be able to supply a bit more than 50 PSI to keep system happy. Number of liters per minutes is also specs BUT not very critical in general as most of these pump can supply a lot more in normal running conditions.

In addition, you need to test all these conditions with a fuel pressure gauge installed in-line (on pressure side hose between tank and fuel rail)
(1) fuel pressure after 2 seconds prime following ignition ON should be close to 50 PSI (do not start engine yet)

(2) wait 30 seconds at least after ignition ON to see if pressure stays the same (should not drop more than a few PSI)

(3) start engine and watch for good constant pressure (50 to 54 would be OK)

(4) re-test after a while to see if fuel-pump (or regulator) does not act up with a hot engine after a long ride.

(5) Keep gauge plugged in-line, after engine is stopped and bike is parked for 10 minutes: recheck if pressure has not dropped much compare your running pressure (system should not loose much pressure - otherwise pump internal valve or injectors leaking).
Nice test setup!
 

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Discussion Starter #13
Problem fixed!

Bought a fuel pressure gauge and had 0 psi pressure at the fuel manifold. Drained and removed fuel tank. Pulled fuel pump assembly out and the hose connected to the fuel filter had come off the nipple.

Reconnected the hose, reinstalled everything and the engine started and ran correctly.

:grin:
 

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Problem fixed!

Bought a fuel pressure gauge and had 0 psi pressure at the fuel manifold. Drained and removed fuel tank. Pulled fuel pump assembly out and the hose connected to the fuel filter had come off the nipple.

Reconnected the hose, reinstalled everything and the engine started and ran correctly.

:grin:
Glad you got it fixed.
 
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