HELP Please - 40 hp Johnson 1992 Model PROBLEM

[sigarmsp226]

New to boating and new to this forum. Need someones help PLEASE. I bought a 1992 Bass Tracker 2 months ago with a 40 hp Johnson motor. Boat ran out great so I bought it. I have used it every weekend and a couple of time during the past weeks with no problems. My local boat repair man indicated that I should allow him to remove the oil injection pump and I shold mix my oil to prevent possible motor damage if the pump ever went out. So I did. Boat has worked great since the removal until yesterday. It started surging, it would allow me to start off and as I started getting some speed the motor started surging up and down, up and down. So today I replaced the bulb, drained the gas / oil mix and replaced it with brand new 93 octane gas, mixed my oil 16 oz to 6 gallons, and even removed the inline fuel filter and replaced it waith a straight pass thru tube unit and replaced the plugs. Went out today and it started doing it again, at first, then for 30-45 min it ran great, then it started doing it again. I can sweeze the bulb unit when this starts and the problem stops. 5 mins later it did it again. Any help on this is MUCH appreciated.

Thanks in advance

Mark in Mississippi

 

[larky]

Re: HELP Please - 40 hp Johnson 1992 Model PROBLEM

not familar with your motor but if squeezing the bulb helps then my guess would be a faulty fuel pump, possibly something to do with the oil injection modification. check connections of hoses, tighten clamps. or could be the diaphrams in the pump went bad. just a guess
good luck

 

[sigarmsp226]

Re: HELP Please - 40 hp Johnson 1992 Model PROBLEM

Thanks for the quick reply Larky. As I read thru several past posts related to this simular situation it seems that your sugggestions as well as a possible tank venting issue and making sure that I use Marine clamps instead of hose clamps is the best way to go. I plan on carring the unit to my local boat master to see what he thinks. Interesting that it cranks and runs good and only does this on ocasion. What is puzzling is that when I sqeeze the new bulb unit the motor picks up back to normal throttle and almost throws me out of the boat. THanks again and if anyone else has comments I am here for the listening.

Mark

 

[JB]

Re: HELP Please - 40 hp Johnson 1992 Model PROBLEM

Howdy Mark.

Welcome to iboats.

First, replace the filter. Then check the tank vent, pickup and fuel line for restrictions and fuel line for air leaks.

Mix your fuel at 1 pint TCW-3 oil to 6 gallons of 87 octane unleaded gas. Premium is no advantage and may even be bad for the engine.

If the above does not help replace your fuel pump with a fuel pump with no oil injection feature. A poorly done disabling of the oil pumping feature of your pump could well be the cause of your trouble. It may be pumping air into the fuel stream.

Good luck, and let us know what happens.

 

[sigarmsp226]

Re: HELP Please - 40 hp Johnson 1992 Model PROBLEM

Mr. JB - Thank you Sir - Interesting comments and I appreciate you spelling it out for me. THought the 93 octane would make it better, thanks for that input. I will replace the filter tomorrow and check to insure that the small tube that is covering the oil injection inlet it secure. One question - How do I check to verify that my tank is properly vented. It is a 13 gallon in the boat tank and not sure haw to check for that.

This is a great site and I appreciate being able to join and learn. Nothing makes me more sick at my stomach than for my 92"new" boat not to run right. Love this thing and have been mad all day for not having been able to fix it. Thanks again for your support..

Mark

 

[tashasdaddy]

Re: HELP Please - 40 hp Johnson 1992 Model PROBLEM

if you have a built in tank the vent is either at the fill point, or on the outside of the boat. manufacturers put them in different places, but they all vent to the outside of the boat so that if they overflow it is not in the boat. you can take an compressed air line and use a rag, etc, to seal and inject air into the fuel fill, you should get the air out of the vent.

i have the 93 40 johnson, i just plugged the oil line going into the motor, and disconnected the sending unit wire. i have had any problems with it.

 

[sigarmsp226]

Re: HELP Please - 40 hp Johnson 1992 Model PROBLEM

Thanks Tashasdaddy - I am going to work on it today and will let you guys know what I find. From reading most of the evening on this site the biggest problem is people suggesting possible solutions and the boat owner not providing feedback to the group when solved. Hope to be back with you in a couple of days with a smile and a solution. Thanks again everyone

Mark

 

[tashasdaddy]

Re: HELP Please - 40 hp Johnson 1992 Model PROBLEM

you are very correct, and it is a real boost to us to know we help you solve your problem. or if we were wrong, and you found another solution.

 

[sigarmsp226]

Re: HELP Please - 40 hp Johnson 1992 Model PROBLEM

One Down - The tank Vent is working correctly and I did exactly as indicated. I placed a compressed air line on the talk gas line prior to the bulb unit and allowed low pressure (30-40 PSI) air to go into the tank. Vent is on the back of the boat opposite side of tank fill cap. Air flowed freely out of the vent. Local boat man is looking at the unit now and I will let you know what he finds. Going to start with replacing the fuel lines and go from there.

Back later with the answer

Mark

 

[sigarmsp226]

Re: HELP Please - 40 hp Johnson 1992 Model PROBLEM

Here is the latest. Local Boat man checked all of the fuel lines and all are good. What is interesting is that my VRO pump ( I do not know what a VRO pump is ) but he described it as being the same as the fuel pump on a car is now knocking. Did this happen because he disconnected my oil injection pump unit or did this thing start knocking as a result of my earlier symptoms ( surging). I stood there while he ran the motor and this thing is for sure knocking. He told me that he has a 90 - Johnson motor that is not oil injected that he is going to pull the pump off of and put onto my motor at a cost of about 100 bucks. No warranty but if it goes out in the next 12 months he will allow the 100 bucks to go towards a new VRO pump ( he said cost on a new pump is about 275 bucks). What do ya think.... Is this the right move or do I just pull this motor off and drop it in the river....( just joking about that second thought)...

Let me know what you thing and can someone tell me in laymen terms what a VRO pump does on this motor. The way I understand it, it is a fuel pump...

Thanks guys

Mark

 

[tashasdaddy]

Re: HELP Please - 40 hp Johnson 1992 Model PROBLEM

seeing he has disconnect the oil side of the pump, and you are premixing, why not just put a straight fuel pump on it, instead of a vro pump. the vro automatically mix the oil and gas. this is the sierra pump for the motor if vro is removed http://www.iboats.com/Sierra_18_735...8122754--**********.935192603--view_id.174141

the oem number is 433387

 

[sigarmsp226]

Re: HELP Please - 40 hp Johnson 1992 Model PROBLEM

Thank you Tashadaddy - I just ordered one form the link you provided. He indicated that he was going to replace my unit with a gas only pump unit but I did not understand or realize the cost. Why pay 100 bucks for a used unit when I can have a new one for 50. Thaks again for your quick reply and I will let you know if this in fact fixes my surging problem. Thanks also for letting me know what a VRO does. Learning something new everyday. Be back with you on Thursday night or Friday after I have a chance to put the boat into the river. He does have a motor tank at his place and is going to try it before he sends me on my way. Thanks again - Follow up later in the week...

Mark

 

[sigarmsp226]

Re: HELP Please - 40 hp Johnson 1992 Model PROBLEM

Tashasdaddy and all - Verdict is in... My local boat man removed my VRO pump unit ( pretty complex unit after seeing off the motor ) and because he removed and blocked off the oil injection line on this motor 3 weeks ago he decided to replace it with the exact pump unit you identified in the link above. He had a used unit and we agreed to have him install it until the new one arrives that I ordered yesterday. He completely removed the VRO unit from this motor. With mixed gas/oil in my tank I took it to the river yesterday and the surge is gone, so far. I was only able to run the boat for 45 minutes at various speeds but in that time no surge. He did recommend that I also use a product called Sea Foam as a additive in my tank. Said I can find it at any parts house or Wal-Mart. My hope is that this stuff is as good as he says it is and will not hurt my motor. Thanks to all for your input and comments.

Mark in Mississippi - Crappie are starting to bite again so to the river I go this weekend to wet my hooks.....

 

[tashasdaddy]

Re: HELP Please - 40 hp Johnson 1992 Model PROBLEM

glad you got it worked out, use the used pump until it goes out, just put the new one on the shelf. installation is only 2 hoses, and 2 screws. Seafoam mixed in the fuel/oil mixture will help keep the carbs clean, and the carbon from building up in the engine. it may smoke a little more at first, but it is cleaning up the motor.

 

[Silvertip]

Re: HELP Please - 40 hp Johnson 1992 Model PROBLEM

To verify if the tank is vented, run the tank fill cap or cover loose/open. If the problem goes away, the tank is not vented properly. If it weren't vented properly the primer bulb may also appear to be sucked flat when the problem occurs (like sucking on a plastic soda bottle causes the sides to cave in because the bottle is not vented).

 

[Cricket Too]

Re: HELP Please - 40 hp Johnson 1992 Model PROBLEM

Sorry, but I'm not understanding why the VRO was disconnected in the first place, and why it wasn't re-connected when the problem started to see if re-connecting solved the problem??

The biggest problem VRO had/has is that people (mechanics) don't understand it and think it's a problem or could be a problem, when in fact it is a very reliable and convenient system.

I would rather have a VRO than pre-mix anyday. I've been running VRO and OMS for almost 20 years and never had a single problem with any.

 

[sigarmsp226]

Re: HELP Please - 40 hp Johnson 1992 Model PROBLEM

Cricket Too - Sorry for the confusing way I defined the situation. The local mechanic had discontinued the oil injection side use on the VRO about three weeks earlier. The day I bought the boat I asked him to look at the motor to see if there was anything I needed to do related to servicing. At that point he indicated that because the motor was 15 yrs old it would be to my benefit to allow him to remove the oil injection tank and block that line and me mix my fuel and oil. Being new in to boating I did what he suggested and started mixing. What my boat repair man told me was that the surging was caused because the gas side of the VRO has a diaphragm in it and it was not functioning correctly, to the point that the VRO pump unit start knocking. Because I was no longer utilizing the oil pump side of the VRO he suggested removing the VRO all together from the motor and attaching a standard OEC vaccum regulated fuel pump made for this type motor. Thus far it has worked. The knocking VRO unit was removed and the regular fuel pump was installed and with 45 minutes use thus far, no surging. Hope this provides a better explanation of the change. He also told me that cost to cost the VRO unit would cost almost $300.00 where as the OEC vaccum fuel pump was $50.00... In you opinion did I make a mistake the day I agreed to allow him to remove the oil tank and block that line? Honest feedback is what I need so that I will not make the same mistake twice....

Thanks Mark