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04 Johnson 175HP How do I know if oil pump failed?

T

TheBrain

Regular Contributor
04 Johnson 175HP How do I know if oil pump failed?

During my last great adventure on the high sea’s 2[SUP]nd[/SUP] day (first day no light) the no oil light came on so I turned off engine.
I have disconnected the oil line last engine running 3[SUP]rd[/SUP] week in Nov. added like 3 gallons of oil to reserve and I always press the bulb to build preasure usally it’s already so hard you can’t squeeze it.

Still the light so I disconnect at the tube just before it enters the engine purged there didn’t observe any air bubble reconnected still the light.
?1.should I have purged at the oil pump?

?2.if my oil pump went south wouldn’t the engine enter limp home mode and not allow me to rev past a certain amount of RPMs?

While I was at the dock preparing to leave I started talking to the man next to me he was having difficulty retrieving over some washed up sand and I asked if he needed a hand.

Anyway man had a set of late 90s 2 stroke yammies they still sounded good asked him about the reduced amount of blue smoke I;m accustomed to seeing he said it sounded good and just run it even w/ the light on. Come to think of it when the engine is warmed up the smoke is reduced I don’t like red lights on my engine error code.
So how
?3.How do I know if oil pump failed?
?4. doe’s the oilpump also pumps the fuel?

50 minutes after last cruise engine didn’t want to start at the rinse off lake. All that three weeks ago now I want to restart the engine.attach image at fresh water rinse off lake
I got good fuel the engine turns over I was thinking about removing a spark plug and look for spark during turning engine over maybe at night in the dark mite be a good plan because the ignition is 12’ away from engine or could I extend the spark plug wire w/ regular wire to watch for spark?
Thanks TB
 

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Will purge at the oil pump hopefully the light will go out.first I need her running. I was hopping for a simplistic engine.

Will check the spark. I’ve already paid to have the I think it’s called the stater just under flywheel replaced last year this part creates the spark.

Plan to install new spark plugs.there where champions in there the mechcanic suggested the NGKs
https://www.ebay.com/itm/332630879785
 
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I would stick with OEM spec Champion marine spark plugs. I’ve used substitutes in the past with poor results. The correct Champion has always served me well.
QL78YC Is available in WalMart.
 
The used NGK spark plug is covered in oil. I assume all 6 are oiled up also.


Are these spark plugs oil fouled preventing ignition?
Thanks
 

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Your motor has to run the Champion plugs (QL78YC) suggested. NGK makes a good plug, but not for this ignition system. Your oil light may be just the sensor on the oil pump? You can mix your gas & oil until you get that figured out. Do you also have a horn for ten seconds when the light first comes on? If you monitor you oil consumption in your oil tank you can see if the engine is using oil. That would prove that just the sensor is bad. Dealers/mechanics that have bad pumps will have sensors that can be changed out. Just a suggestion. The complete pumps are very expensive now!

 
I got your message. I can't say about the plugs being fouled for sure, but it doesn't really matter. You can not run NGK plugs in this motor. The ignition system will not tolerate that type plug. This family of motors is not sensitive to fouling plugs. CDI will tell you only Champion builds a plug for this motors ignition system.
 
dam I just gave $18. for the NGKs and I've installed them havn't attempted to start engine yet.

spark is spark can't understand why NGKs won't work on the johnson.

confused why boat mechanic suggested the NGKs

thanks TB
 
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OMC/BRP has built that motor sense 1991 was OIS (Optical Ignition System) on it & still have mechanics & parts houses suggest NGK equivalent spark plugs. In this case NGK does not make a plug that will work with this system. The system is sensitive to noise & interference from the plugs & wires. That is not the problem with your oil horn, but will lead to running problems. The NGK plugs will work in other OMC engines, just not the V-4/V-6 with OIS ignition. Sorry.
 
Did you do the compression test? Stop taking lines off of the oil pump there is a certain procedure for bleeding those pumps. There is also a certain procedure for testing them. Is the horn/light low oil or no oil? What do the other 5 plugs look like. The no oil light should send the motor into S.L.O.W mode. The low oil light wont. Get a factory manual for your motor.
 
This is a carbureted engine. No oil WILL NOT put engine into SLOW. Only overheat puts motor in SLOW. SLOW stands for Speed Limit Overheat Warning. That is why there is a blocking diode in the wiring harness. So only the temp sensors turn on SLOW. Please don't confuse the issue. DFI motors are different.

Dan in TN
 
t2stroke said:
This is a carbureted engine. No oil WILL NOT put engine into SLOW. Only overheat puts motor in SLOW. SLOW stands for Speed Limit Overheat Warning. That is why there is a blocking diode in the wiring harness. So only the temp sensors turn on SLOW. Please don't confuse the issue. DFI motors are different.

Dan in TN
Click to expand...
You can tell that to my 175 johnson that went into slow mode when the oil sensor failed.
 
t2stroke said:
OMC/BRP has built that motor sense 1991 was OIS (Optical Ignition System) on it & still have mechanics & parts houses suggest NGK equivalent spark plugs. In this case NGK does not make a plug that will work with this system. The system is sensitive to noise & interference from the plugs & wires. That is not the problem with your oil horn, but will lead to running problems. The NGK plugs will work in other OMC engines, just not the V-4/V-6 with OIS ignition. Sorry.
Click to expand...
Here’s the best deal I can find on

Champion Spark Plug Copper Marine 938M QL78YC 4 Pack what doe’s the 938M mean. Is this still the correct plug?

https://www.ebay.com/itm/Champion-S...380727&hash=item3aef2b82c7:g:8oYAAOSw6Q1ZuEa7

when I did my repower I installed a brand new binacale however I never plugged in the warning horn I think it requires splicing the purple/brown wire. I will eventually connect the horn kindof of want the engine up and running good.

thanks


flyingscott said:
Did you do the compression test? Stop taking lines off of the oil pump there is a certain procedure for bleeding those pumps. There is also a certain procedure for testing them. Is the horn/light low oil or no oil? What do the other 5 plugs look like. The no oil light should send the motor into S.L.O.W mode. The low oil light wont. Get a factory manual for your motor.
Click to expand...
havn't done compression test yet. I need to either borrow or buy a guage.

The no oil light is the topmost light which has stayed on, even w/ this light on the engine ran fine at all RPMs remember this is a carbed engine carbs arent controlled w/ a computer but a throttle cable.

the other 5 plugs looked oil fouled as well couple of the electrodes the metal is worn away virtually doubling the gap however even w/ worn out plugs she should crank may run poorly but running is better than none running.
thanks
 

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Yes the QL78YC Champion is the correct plug. I believe 938M is the stocking number Champion uses. M is for marine I think.
On your horn hookup the purple wire goes to your A terminal of the ignition switch. This is swtich on 12v. That provides the self test feature of the horn. You should have a short black lead? That goes to the ground in the control box. The brown lead goes to the brown wire from the harness. That is from the temp sensors off the cylinder heads.
It is possible if you do not get a warning horn (when the horn is hooked up) that the gauge is bad. I have seen them go bad.

Dan in TN
 
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Dan in TN. Do you have to use the BIG print all the time ?? I'm sure all of our members read the regular print all the time just fine???????
 
Sorry, I like the big print. Not all caps. I'm not yelling at anybody. I'm getting old. Easier for me to read. Wish everybody else would step it up a size or two.
Is this better for you?

Dan in TN
 
I recently found my 1994 175 with huge amounts of oil in the engine. I took the carb bowl drain plugs out and lots of oil in them preventing the engine from starting. After pinching off the oil line, it finally started with clouds of smoke and black slim shooting out the exhaust. Could be you have the same problem. Checking my options for the VRO.
 
I got the champions in there and will attempt ignition today, my garden hose needs to be extended three feet.

I need to hussle getting ship shape. I'm currently expanding my usable aft. deck 25" wide X 12"deep the section in between my knee brace, this is much needed decking, mainly to protect bilge pumps sys. will be big help in collecting tree leaves the additional footing will be a major improvement.

this new aft decking will hold 2 five gallon buckets 1 regular for bailing/bleeding/washing my pin fish trap inside it.will post image later.
Next GOM cruise after or on this weekend.

thanks for tips John on the the oil I will drain each bowl and inspect.

I've looking into having a spare fuel/oil pump onboard Remember I cruise for 3 days at a time so I'm a big believer in redundancy.

the pumps are $350. also being informed they are very reliable. I've read alot of people just remove the VRO and premix.
 
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update: last week cruised the GOM rained/thunderstormed 80% the whole 5 days.4 times I went out engine started and ran excellent.

I believe the oil reservoir was low causing the low oil light so I added 2 gallons no more light.

the saltwater was so diluted the fish left the area, fish 4 me 0 I've never been 0 for 4 not counting the 5 small (bait fish) caught under the bridge

on to next issuse the flush port where the gargen hose attaches to is all crossthreaded up now the water pump pea is like a spary not stream.
 
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