Testing a 1995 Mercury 200 XRi EFI engine that is not mounted to a boat

Texasmark

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Re: Testing a 1995 Mercury 200 XRi EFI engine that is not mounted to a boat

Not being smart, but very carefully. Personally I wouldn't do it do to it's size.

Mark
 

sschefer

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Re: Testing a 1995 Mercury 200 XRi EFI engine that is not mounted to a boat

Is the engine on a stand? If not you can build one. I belive there are plans for one on here somewhere. I sand bag the legs of mine just to keep it from moving around and then put a battery, remote starter switch, ground wire to the igniton for shut off, fuel and a water source (muffs) to them and fire them up. If the stand is beefy enough to hold a 400+ lb motor solidly it won't go anywhere when the motor is running. Throttle is controlled manually as well as shift. It's pretty easy if you think it through.

The ground wire to the ignition is left unconnected on one side when trying to start the motor. To stop it, just touch the bare end to a known ground and it will kill the engine.

On these motors, igniton is always on unless it is grounded. Once the motor hits around 300 rpm (starter) it will produce enough spark to run. It does not get spark from the battery, it gets it from the stator located under the flywheel. There have been cases where these motors start spontaneously, it's rare but can happen so be sure to pull and ground the plug wires while you're working on the motor.
 

Faztbullet

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Re: Testing a 1995 Mercury 200 XRi EFI engine that is not mounted to a boat

On these motors, igniton is always on unless it is grounded. Once the motor hits around 300 rpm (starter) it will produce enough spark to run. It does not get spark from the battery, it gets it from the stator located under the flywheel. There have been cases where these motors start spontaneously, it's rare but can happen so be sure to pull and ground the plug wires while you're working on the motor.
This is correct on carb motors but a EFI needs the control box as you must turn the ECU on for it to supply fuel....
 

CharlieB

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Re: Testing a 1995 Mercury 200 XRi EFI engine that is not mounted to a boat

With the plug wire grounded you can crank the motor to test compression and spark.

With the motor upright, you can test fuel pressure to the injectors, rig a fuel hose and pump up the primer bulb, disconnect the ground side of the high pressure fuel pump from the ECU and rig a ground wire to turn on the pump. I am assuming that you have the battery cables connected. Check fuel pressure to the injectors. Note, this will only tell you that the pump is capable of building pressure, it will NOT tell you if the pump will maintain that pressure at the WOT flow.

Note that you still will not be able to determine if the ECU is functioning until you actually fire the motor, and even then you cannot know if the ECU and injectors are capable of WOT operation without running the motor in a test tank or on a boat.

You 'could' send both the ECU and injectors to Tony Brucado for testing.

EFI's are fine motors, but......... they do require a bit more homework in determining if they are a good if you are not able to test drive one.
 

Orangegator

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Dec 15, 2011
Messages
2
Re: Testing a 1995 Mercury 200 XRi EFI engine that is not mounted to a boat

Is the engine on a stand? If not you can build one. I belive there are plans for one on here somewhere. I sand bag the legs of mine just to keep it from moving around and then put a battery, remote starter switch, ground wire to the igniton for shut off, fuel and a water source (muffs) to them and fire them up. If the stand is beefy enough to hold a 400+ lb motor solidly it won't go anywhere when the motor is running. Throttle is controlled manually as well as shift. It's pretty easy if you think it through.

The ground wire to the ignition is left unconnected on one side when trying to start the motor. To stop it, just touch the bare end to a known ground and it will kill the engine.

On these motors, igniton is always on unless it is grounded. Once the motor hits around 300 rpm (starter) it will produce enough spark to run. It does not get spark from the battery, it gets it from the stator located under the flywheel. There have been cases where these motors start spontaneously, it's rare but can happen so be sure to pull and ground the plug wires while you're working on the motor.

The engine is securely mounted to a stand with additional overhead straps to help stablize it. There is a water source, just need to figure out how to start it to record compression. I know for a fact that the engine runs well, it came off of a 1996 Dominator 202 by Legend, I've seen it in action.

Thank you for the info!
 

Faztbullet

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15,589
Re: Testing a 1995 Mercury 200 XRi EFI engine that is not mounted to a boat

Attach battery cable to engine and just jump solenoid to get a cranking compression. If you want it to start ,attach a jumper from the 12v+ to the purple terminal strip and this will turn ECU on. Then you can jump the solenoid to start but make sure throttle arm is at idle position.
 

sschefer

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Re: Testing a 1995 Mercury 200 XRi EFI engine that is not mounted to a boat

The engine is securely mounted to a stand with additional overhead straps to help stablize it. There is a water source, just need to figure out how to start it to record compression. I know for a fact that the engine runs well, it came off of a 1996 Dominator 202 by Legend, I've seen it in action.

Thank you for the info!
You're welcome but I did miss the step about putting 12v+ on the ECU. Thanks Faztbullet for catching that. I've got a portable dash on a rolling stand that has three different harness connectors for the older motors so I completely missed telling you that part. Sorry.
 

Faztbullet

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15,589
Re: Testing a 1995 Mercury 200 XRi EFI engine that is not mounted to a boat

I thought about building a portable breakout box a couple of years ago,but the dash sounds better!! How about a picture of it as to get idea as it is mounted and wired as i am thinking I could add a OMC harness. My original idea was to make some adapter harnesses to fit various motors but proved to be a pain.
 
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