1990 Johnson 175

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matthewsligh

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My 1990 Johnson 175 runs great, but is difficult to start cold and blows a lot of smoke. My brother said I should disconect the oil tank and mix the oil and gas in the tank. Is this a good idea, or should I just stay like I am. Thanks for any suggestions you can make.
 
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Chris1956

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Re: 1990 Johnson 175

And that fixes what problem? Smoking upon start up can be caused by extra oil in carbs due to gasoline evaporation. What does pre-mixing do to solve that?
 
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Chris1956

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Re: 1990 Johnson 175

Do you use the choke? Do you advance the throttle for cold starting. Does that motor advance the throttle automatically (Quickstart system)? Should it?
 
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emdsapmgr

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Re: 1990 Johnson 175

That engine should have quickstart-a great help when coldstarting. It is really a bear to start when cold if the fuel primer (choke) system is not working. You can test by pulling one of the tiny hoses off the top of the top carb, the choking the engine. Fuel should pulse out of that hose.
 
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Chris1956

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Re: 1990 Johnson 175

Sorry Matt, I was rude. if the oil injection is working, I would recommend you leave it alone. It is not part of the problem you described.
 
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matthewsligh

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Re: 1990 Johnson 175

Thanks for the insight, folks. The choke does work, and I do advance the throtle... and it does start eventually. If the smoke does come from evaporating gas in the carbs, hopefully that is not harmful. What is a quickstart? I would love to hear more about that... please provide any information that you can. I guess my main concern on this older boat is that I am on a long run and the oil injection system fails. I would hate for it to leave me stranded. Are these systems reliable enough for me just to not worry about them?
 
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ljrichey

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Nov 1, 2010
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Re: 1990 Johnson 175

matt--those old V6s are good motors--their only problem is they eat the fuel like a starved pig--i would leave the vro system in tact as long as it is operating normally--read somewhere in these forems about starting these old v6s that helped me--bulb tight-key on -hold choke in for around 8 seconds before cranking--retighten hand fuel bulb--choke & crank from there--you may not have to choke anymore--sure been savin on my starter and batt--wouldn't hurt to try it next time out just to see
 
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matthewsligh

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Re: 1990 Johnson 175

ljrichey said:
matt--those old V6s are good motors--their only problem is they eat the fuel like a starved pig--i would leave the vro system in tact as long as it is operating normally--read somewhere in these forems about starting these old v6s that helped me--bulb tight-key on -hold choke in for around 8 seconds before cranking--retighten hand fuel bulb--choke & crank from there--you may not have to choke anymore--sure been savin on my starter and batt--wouldn't hurt to try it next time out just to see
Click to expand...

Great advice... many thanks. I will try that this weekend. Thanks to all of you guys for the suggestions... I am going to leave the system as is, try the new starting technique, and run this boat as long as it will let me!!! You are right about the fuel... it is thirsty... but it has solid power and good cruising speed for me.
 
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ljrichey

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Re: 1990 Johnson 175

Matt--the one thing i forgot to mention is to be sure that your warning system is functioning as it should--that sys should have heat warning,low oil warning,oil pump or mix warning,restricted fuel warning --horn chirp with ignition switch to the on--
 
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emdsapmgr

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Re: 1990 Johnson 175

Quickstart temporarily advances the spark (internal to the power pack) each time the engine is started. If the engine is warm, it will fuction for just a few seconds. If cold, quickstart will keep the spark advanced till the engine heats up to just under 100 degrees. One of the biggest problems on these engines are the factory-original plastic carb bowls. The all warp over time and cause fuel leaks at the seam of the carb body. They can even leak air into the carbs, leaning them out. If yours are not leaking when you prime the fuel hose bulb or tilt the engine, consider yourself lucky.
 
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krimi

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Nov 17, 2010
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Re: 1990 Johnson 175

My 92 200 hp was also very hard to start. Drained some batteries. I added a hand pump near engine. It was much easier to get fuel to the engine by pulling it rather than pushing it from under center console. My starting procedure is to pump the ball till full. Hold choke in, advance throttle, crank, pump ball hard again. Say a little prayer, avoid eye contact with my wife. Then I choke and pump the throttle back and forth..(I know its not supposed to do anything) and crank till I get it going. I went from 25 minutes or longer to 3 minutes. I think the biggest problem people have is not getting fuel to the carbs. I mix, and yes it smokes.
 
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Chris1956

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Re: 1990 Johnson 175

Krimi, Most newer 2 cycle motors have a vapor seperator that is filled by the primer. You do not actually pump up the carbs directly anymore. This can lead to some cold start issues. Tell the wife that the darn regulations forced the installation of systems that make it hard to start. Blame the democrats (or Republicans, your choice). You may also blame the commies, chinease or any other group you want. Let her know it is not your fault!
 
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matthewsligh

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Re: 1990 Johnson 175

OK... I took all of your advice, and the motor starts much more quickly. Still smokes like a beast while warming up, but at least I did not tie up the launch site for too long. Had three great days of running the rivers around St. Simons Island, GA.

New Problem... Yesterday, when we started up to go fishing, after warming up for a little while, the hot horn went off. I looked around to the motor, and no water was coming out of the water discharge. I shut down the motor... messed around with the hose to see if it was clogged or somethign, and started back up. Still hot, shut down again, messed around again, started back up. At this point water started coming out... horn went silent... and after 15-20 minutes of idling with no further alarm, we decided to go on out, even though water was not coming our as much or as fast as I would like to see. We ran alost a 1/4 tank of fuel with no problems, and the stream increased as the day went on.


Question: Does this sound like a water pump going bad to you guys? Or could it just be a clog? Is there any other proceedure I can try to clear the line, or is it time to drop the lower unit? Thanks!!!
 
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Chris1956

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Re: 1990 Johnson 175

When was the last time the waterpump was serviced? If you don't know, or never, it is likely time to do it. Cooling water passages do not clog easily, so that is not likely the cause.
 
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emdsapmgr

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Re: 1990 Johnson 175

The telltale is plumbed close to the front of the cooling system on that engine. It is a reasonable measure of just how good the impeller is. If you have no telltale, there is either a problem with the impeller, or you have debris in the lower unit passages. If the engine was run and no water comes out, the impeller may have run dry-possibly shortening it's life span. As durable as these OMC V4/V6 impellers are-why take a chance. Pull the lower unit and replace the impeller. That will give you a chance to inspect the passage from the water pickup grills to the underside of the pump housing.
 
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Seantracker

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Jun 30, 2011
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Re: 1990 Johnson 175

I'm going to highjack here...I have a 94 Johnson V4 115 and this past weekend got beached on a sand bar. (operator error...follow channel markers!)
Anyway, I am not getting any flow out the telltale and I'm assuming I got a ton of sand in the lower unit. How hard is it to drop the lower unit? Are there any "clips" on the shift linkage or does it slide right off?
I want to replace the water pump anyways, it's been 3 years.

Thanks
 
wolf81tx

wolf81tx

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May 31, 2010
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Re: 1990 Johnson 175

Seantracker dropping the lower unit and changing the impeller is not hard at all. If this is your first time doing this I would set aside 2 hours for the project. I can do mine in under an hour. First thing is if you do not a shop manual for your motor get one. Second do some reaserch, sometimes these manual can be hard for the average guy to understand and they almost always make a job look harder than it is but the info they have in them is priceless. You can even got to youtube and most likely find a video of someone changing the impeller. Third get all parts, tools, sealants and lubricants together. Nothing sucks more than getting halfway into a job and realising you don't have everything you need. Take your time and learn. You can read every tech manual out there and still have not learned a thing until you actually do it.
 
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