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Matthew John
Matthew John, Marine Mechanic
Category: Boat
Satisfied Customers: 30
Experience:  Marine Technician, Certified in MERCRUISER AND MERCURY OUTBOARDS (Current), EVINRUDE, SUZUKI, YAMAHA, HONDA.
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I have a 1998 mercury sportjet 175 xr2 with a bad oil pump

Customer Question

I have a 1998 mercury sportjet 175 xr2 with a bad oil pump drive gear. I decided to premix my tank when the oil alarm turned on while I was boating the other day. The oil alarm came on, 4 beeps every two minutes, and I did not smell two cycle oil burning so I got worried. I unhooked the output of the oil pump and started the motor. No oil. I suspect bad oil drive gear on the crank shaft as this is common. I purchased the oil pump block off kit and can remove it all and do premix from now on. However the alarm keeps beeping 4 times every two minutes. Disconnecting the oil float switch is fine since this motors float switch is at disconnect with full tank, however the oil pump rotation sensor seems to require a pulsing signal and I do not know how to fake this to quiet the oil alarm.
JA: Sometimes boat issues seem like they'll be really complicated, but end up being easy to fix. The Marine Mechanic I'm going to connect you with knows all the tricks and shortcuts. Is there anything else important you think the Marine Mechanic should know?
Customer: I tried disconnecting the oil pump rotation sensor and as I thought no signal will trigger the alarm. My understanding is the ecu looks for rotations during engine rotations.
Submitted: 2 months ago.
Category: Boat
Expert:  Matthew John replied 2 months ago.

Hi my name is***** to Just Answer ! I will be assisting you.

Expert:  Matthew John replied 2 months ago.

I would be removing the Oil Warning Module Or just simply disconnect it. (all wires).

Regards,

Matt

Customer: replied 2 months ago.
If I disconnect the oil warning module does the overheat alarm and all other functions still function? I thought it was an ecu but I guess the only function is oil alarm?? Thanks.
Expert:  Matthew John replied 2 months ago.

Yeah, no worries!

You can test the Temp alarm with Ignition on, Disconnect Temp Switch (Tan/Blue wire) at cylinder head and connect to earth.

You should be all good to go!

Let us know how it goes!

Please don't hesitate to let me know of any concerns you may have in the future!

Be sure to hit my Star Rating ! ! ! ! !

All the best!!!

Matt

Customer: replied 2 months ago.
It looks like my manual for 175 xr2 calls this the TKS ECM and I notice the powerhead heat sensor brown wire comes into it. Please look at my manual (uploaded) as it seems slightly different, is tan on your diagram same as brown on mine?
Customer: replied 2 months ago.
It all looks the same except tan replaces brown on your diagram. Is that from the 200hp outboard manual that is supposed to be the same as my 175 xr2? Are you saying the heat alarm should still work after disconnecting the ECM and I can test the temp alarm by connecting tan/blue temp sensor wire to ground and that should sound the alarm? I think that sounds good, man you're fast and know your stuff. I'll try tomorrow and leave awesome ratings if all works as it should.
Expert:  Matthew John replied 2 months ago.

Ok! Great!

Customer: replied 2 months ago.
One more note regarding this. I saw this on the web, is there any merit to the brown blue wire having to be connected to the terminal that goes to the buzzer? see the following -Its very easy to remove oil injection. Its been a while since I removed oil injection so bare with me.Remove oil tank and two lines that come from boat and hook to engine.
Remove the check valve on the side of the engine that the oil tank gets pressure. Install a 1/2" pipe plug.
Remove engine mounted oil tank.
Remove the oil gear from engine. The best thing to do is to install the oil gear plug available at local mercury dealer. Installing the oil gear plug prevents a brass bushing from falling out of its desired position.
Remove oil warning system boxes and oil gear magnetic pickup from engine.
If the engine is and EFI engine then you must plug the hole in the bottom of the fuel tank that came from the oil gear. Its a 1/16th pipe thread.(This is where my memory gets foggy)
And if anyone can correct me please do.
There is a brown with blue strip (if I remember correctly) that must be relocated on the starboard side electronic panel. what happens is the wire that ran through the oil warning system (thats been removed) is put on the terminal that leads back to the buzzer.
What then happens, is that the buzz that was heard when you first turned the key to the on position, doesn't sound any more. But the over heat alarm still sounds when an overheat condition exist.
Expert:  Matthew John replied 2 months ago.

Three wires meet up. You remove your brown wire, two wires remain on terminal board. They will be the brown/blue's.

Customer: replied 2 months ago.
ok so it's still wired and not necessary. The only other concern since I am studying the shop manual now, I notice the ECM I will be removing also seems to control the enrichment soloniod, will I lose it's function? Does it matter much?
Expert:  Matthew John replied 2 months ago.

Yeah...I wasn't aware of that connecting to the enrichment solenoid at all. For me to access the right service manual for your engine I would need the serial number from your motor. At this stage I would be testing the O H alarm, then go to the water and test it.

Thanks!

Matt

Expert:  Matthew John replied 2 months ago.

If you were unsure about what I meant at the terminal block...It easier to just snip your brown wire when removing the Oil Control Module.

Cheers!

Customer: replied 2 months ago.
Motor is sportjet 175 xr2 1997-98 powerhead OE203000 see attached. Do I need the enrichment?
Expert:  Matthew John replied 2 months ago.

Yeah mate...The manual you have there is way older than your motor. Keep it simple and maybe just wait until you get to your mother and see if is the configuration that we originally went with. Things have just got way too complicated.

Cheers!

Matt

Expert:  Matthew John replied 2 months ago.

You motor...Sorry! I'm flat out typing!

Expert:  Matthew John replied 2 months ago.

Yeah hey,

I tried the serial number at boats.net and it didn't recognise.. btw it's; 0E203000 (should be a zero at the beginning), if you could just double check it for us...

If no luck with the serial.. can you send us a couple of pics of the engine and the Oil Control Module?

Thanks!

Customer: replied 2 months ago.
Serial number is *****
Customer: replied 2 months ago.
by the looks of the diagram one side of the enricher comes from the module I will be removing. Two purple wires to the enricher stay intact, the other wire yel-blk which goes to the ecm will be unhooked. I do not think the enrichment solenoid would work like this so I am wondering if the yellow black from the enrichment solenoid needs to be hooked up somewhere?
Expert:  Matthew John replied 2 months ago.

Have you been to the boat at all and checked it??

Customer: replied 2 months ago.
I got the serial number yesterday but didn't have time to unhook the ecm. Hopefully later today.
Customer: replied 2 months ago.
I saw the enrichment solenoid addressed on a forum but with very little detail, since your recommended removal of the ECM will comepletely remove connection to one of the two wires going to it I believe it needs to be addressed. I think I'd have to run a wire to the ignition for the push key in feature to enrich in order to keep the formerly automatic enrichment feature at all. Based on my limited knowledge of mercury outboards I suspect it may work with no enrichment but I will be upset when I go to cold start after not running for a while. The enrichment solenoid on my motor has two wires coming in, two purple wires that merge into one, one form the ECM I will remove, the other side of purple is supposed to go to the cockpit harness. The 2nd and only other wire to the enrichment solenoid is the YEL/BLK that is currently only connected to the ECM. The ECM will be removed so one side of the solenoid will not be connected at all. Since at least one of the two wires will be disconnected this will render the solenoid useless unless I connect it to something likely the push key function. What signal does the enrichment solenoid require to activate the wires are PURPLE = ? YEL/BLK = ?. What signal does the key push provide once I locate the terminal on the back of the ignition? I suspect 12v. Is it as simple as hooking the one wire from the ignition to the YEL/BLK or Purple and grounding the other side? I'll RTFM on testing solenoid as I think that would clue me in on how to keep it functional.
Customer: replied 2 months ago.
again my motor serial number is *****
Expert:  Matthew John replied 2 months ago.

Yeah, hi mate.

I was able to look up your model and check the whole parts catalogue for that serial and they do not list an Oil Control Unit for that model.

When you removed the Oil Pump, you say there is a pulse sensor in it, indicated by two wires and a plug... Can you send me a pic of the actual Oil Control Module on your engine? Because, I think that we may be going off two different manuals...

Thanks!

Matt

Customer: replied 2 months ago.
Will do but I am tied up until Monday. Thanks!
Customer: replied 2 months ago.
It's called TKS ECM
Customer: replied 2 months ago.
The two PDF photo's I uploaded before should show you how it's wired. I took photos of my manual. The information in my manual appears accurate, mercury sportjet 175 xr2. I have not tried unplugging the tks ecm yet. It does appear the tks ecm controls the enrichment solenoid so I wonder if I remove that box, if I can wire something up to keep the enrichment solenoids function?
Customer: replied 2 months ago.
Do I need to pay more or more info? What if I just cut the wire to the alarm? I'd lose overheat warning but it may be easier to add a temp gauge than to figure out how to make the enrichment solenoid work. My understanding is it currently uses temp and other info to engauge and I would lose that if I remove the ecm right?
Expert:  Matthew John replied 2 months ago.

Hey there,

Just a couple of points...

1) The manual you have is way too old for your engine.

2) The TKS ECM is the engine management computer for your engine.

3) Your engine does not have an Oil Control Module and just wanted you to confirm this by taking a pic of your Oil Pump and there should be no wires coming out of it.

Expert:  Matthew John replied 2 months ago.

The Oil Pump that you removed from the engine already... Do you have it?

Customer: replied 2 months ago.
My oil pump has a rotation sensor, so yes a wire comes off it. I'm 99.999% sure the rotation sensor is what is causing the beeping since the beeper is beeping and the pump is not pumping oil. I also tested the oil tank cap sensor and it is functioning correctly, the cap sensor has two wires one to ground, when the oil is low it connects ground to trigger. The oil pump is still on the motor right now. Again yes it has a sensor on it held on it with a small screw, and a single wire comes out. It does correspond to my manual. I am not sure why my manual being old matters as the wiring and components are the same as the manual I have? There are two other small electrical boxes on the same side of the motor as the tks ecm. I thought you said you wanted a photo of the oil control module, meaning the box the wires go to. I will get a photo of the oil pump, it looks exactly as it looks in my manual. It is a ONE wire rotation sensor with a small screw holding it.
Customer: replied 2 months ago.
Three wires from the rotation sensor not one as I previously stated. In order to keep the enrichment and replace overheat beep with a temp gauge to the temp gauge wire. There appears to be an unused temp gauge wire that I should be able to utilize. No beeping anymore but the temp gauge should compensate.