Electric fuel pump?

[rottenray]

I have a 1992 Johnson V-4 120HP that is miserable to start after setting a few days. I have read all of the posts relating to this and followed Tashasdaddys rcommendations. I had it to my local boat repair tech who I have a lot of confidence in to be checked out. Compression is good, carbs were gone through, etc. The tech advised me to put the motor in the down position while setting in the yard on the trailer. This helped somewhat and I did install a fuel shut off in the line that I close while parked. This seemed to help a little but it still starts hard and smokes really bad when initially started. Runs good and starts first turn after that. Even if we are out for several days it will start OK everyday.
My question is: The mechanic said that some people put electric fuel pumps on these motors to aid in starting. Have any of you had experience with this? Also my boat had a water filter installed by a shop before I bought it and the filter sits really high on the transom. Could that be causing any problems? I found an electric fuel pump for about $55.00 that is rated for marine use.
Thanks!

 

[ezeke]

Re: Electric fuel pump?

I doubt if the fuel pump has much to do with your problem.

You need to be sure that QuikStart is functioning properly when you start the motor; without it, your engine will always be hard to cold start.

 

[wilde1j]

Re: Electric fuel pump?

If you have an OMS pump, with the oil side being used, it's possible that oil is continuing to flow into the carbs after shutdown. One of my neighbors had this condition two years ago, and replacing the pump cured it. The heavy smoking is the clue. I'll bet if it's only shutdown for a short while, it doesn't smoke much when started. Very easy to confirm. With the motor not having run for a few days, drop one of the float bowls and see how much oil's in there. If you've got mainly oil in the float bowls, starting will be very hard until the oil gets diluted with plenty of gas.

Electric fuel pump is a bad idea from a safety standpoint, unless you incorporate something to shut it off when the motor isn't running for a certain time period.

 

[rottenray]

Re: Electric fuel pump?

Thank you both for your replies. I am kind of shooting in the dark but thought the elect pump was kind of a desperate move.
If I did install one I had thought to switch it and only use it for starting. The oil continuing to flow after shut down makes total sense. You are right that on starting after the initial cold start there is what I would consider a normal amount of smoke.
Would either of you suggest disabling the VRO system and go to premix?
Thanks!

 

[kenmyfam]

Re: Electric fuel pump?

I would suggest finding the real cause of your issues.
An electric fuel pump is a very bad idea in my opinion. Accident waiting to happen !!!

 

[ezeke]

Re: Electric fuel pump?

The reason that I don't think the pump is the problem is that if it were, you would have the problem all of the time, not just when starting.

The VRO2 pumps are pretty good, but yours is getting a little old if it's the original. The safe bet is to use the pump as a premix pump - costs nothing to change it.

The problem with the electric pumps is that there is no regulator to automatically stop them when the engine stops. You can't just use a pump for starting; something has to continue to supply the fuel to the float bowls for the engine to keep running.

You might want to service your recirculation check valves - after you do a thorough de-carbon treatment.

Loopers hate running cold, so you want to be sure that your thermostats are working properly.

 

[wilde1j]

Re: Electric fuel pump?

The reason that I don't think the pump is the problem is that if it were, you would have the problem all of the time, not just when starting.

With my neighbor's boat, the problem was only the first start of the day and it smoke like the primer was in the manual "on" position for about 5 to 10 minutes, then was fine the rest of the day. The oil leakage rate was apparently very low and it took a considerable time to build up enough to present a starting issue. When he replaced the OMS pump, all was cured. That's obviously an expensive fix, since the VRO/OMS pumps are > $400.

Your suggestion to go to pre-mix and disable the oil side of the pump is clearly the least cost course of action. I expect the oil side must have a valve that's similar to an anti-siphon valve and it's malfunctioned in this case, but I've never bothered to pull the oil side apart, since it isn't serviceable.

 

[rottenray]

Re: Electric fuel pump?

Once again thank you all for your replies and the suggestion to find the real problem is a good one I think. I have a Clymer manual for this engine so I will spend some quaility time with that and see if I can learn more about the VRO system. From what I have been able to glean from the replies the VRO has both a fuel pump and an oil pump? About 5 years ago I used to post and read this forum a lot and I seem to remember there was a thread on how to unhook the VRO system. If the problem is in the system which it certainly sounds like it is, rather than spending $400 for a new pump I think I would go to premix instead. I searched for that thread on disabling the VRO but was unable to find it. Possibly someone could direct me to that thread or give me the condensed version of how to do it. I love the boat and I love that old motor after the initial start and plan to keep it at least 5 years longer.

 

[Dhadley]

Re: Electric fuel pump?

Yep, I agree to find the real cause of your issues. Yes, there could be pump issues especially if the oil tank is higher than the pump, like what we find on some deck boats or pontoon boats. But start with the basics. How's the compression? Motor running correctly? What plugs are you running? How old are they? How old is the fuel?

After - after - you answer those questions detail your starting proceedure. Exactly what you do to start the motor when it's cold.

 

[wilde1j]

Re: Electric fuel pump?

Look at the sticky "Top Secret Files" to find info on disconnecting the VRO/OMS pump.

 

[rottenray]

Re: Electric fuel pump?

Thanks Dhadley,
I stored the boat last winter with Stabil in about 3/4 tank of fuel. I use the mid range gas from Mobil rated at about 89 octane. Unfortuantly in the peoples republic of NY all fuel has 10% ethonal. That fuel has all been run out now and the fuel in the boat is usually around 2 to 3 weeks old depending on how often I go fishing. We live close to Lake Erie and Ontario so we go often. This year I have been using the marine formula stabil in the recommended ratio. I use Champion QL78YC plugs gapped at .035 and the set in the motor now were new in the spring so have probably 10 hrs at the most. Since it is so hard to start I change plugs fairly often. The motor runs really good after that intial hard smokey start. Has good power and is on a Crestline 196 Eagle SST that will do 40MPH with just the wife and I under favorable wind conditions. (That is GPS mph). Motor sounds good, idles smooth and starts great after the initial start. Can be 10 minutes, 2hrs or 12hrs later and will start right up.
As I mentioned it is a Crestliner and the oil tank sits on the floor in the very aft part of the boat and is well below the engine level. I have a compression test done almost every year at my local shop and I don't remember the numbers but they were all good and not much variation.
When I go to start the engine once in the water normally tied up to the dock I pump the squeeze bulb (on the fuel)until it is hard then pull up the fast idle lever, turn the key while pushing in on it to activate the primer. When the engine starts which it will usually do within a few seconds I release the primer. This is where it can go either way, sometimes if I do that procedure again it will run rough and cough and smoke and I sometimes will push the primer again if it sounds like it is dying out. Sometimes it will run rough for a little while and then you can hear it start to increase rpm and smooth out. That is on a good day, on a bad day I do the same thing initially but then if it doesn't want to run I sometimes pump the bulb again and try the procedure over again and again. It will eventually start but by that time there is so much smoke other people at the dock are choking and trying to breathe! After it smooths out enough to drop the fast idle lever we leave the dock and it usually runs fine getting out of the harbor and then I open it up and it runs fine. We can shut it off to fish and as soon as I turn the key it will start right up.
I had it to my local shop last year and they replaced some fuel lines and the squeeze bulb. It is hard to duplicate the problem because once you get it running it is fine.
Hopefully this will help you figure it out and once again thanks!

 

[Dhadley]

Re: Electric fuel pump?

You may have the diaphram issues as mentioned before. Once that is verified and corrected (if needed) we can get back to your cold starting proceedure.

1- squeeze the fuel bulb (not the oil bulb) until firm.
2- Turn the key to "On" - do not engage the starter - and push the key in. This will release fuel into the intake.
3- Hold the key in and count to 8.
4- Now turn the key to the "start" position. If the motor is in good shape the motor will start almost instantly. You may have to tap the key a couple of times as it warms up.

We'll assume the thermostats are in and working, the carbs are clean and the ignition is right. You don't need to advance the throttle, the motor will do that by itself.

 

[rottenray]

Re: Electric fuel pump?

Thank you all and especially dhadley for the help. I will try the procedure you outlined. It appears that I should not lift the fast idle lever? I was holding the key in while the motor was turning over not prior to engaging the starter. So that could be part of the problem.
Thank you all so much!

 

[Dhadley]

Re: Electric fuel pump?

That could indeed be an issue. If the starter is engaged first and then the primer may not get enough voltage to kick in. Starters can use up a bunch of volts.

 

[rottenray]

Re: Electric fuel pump?

Thanks again for all of your help. I will put these ideas into practice next weekend and let you know how I make out. I really like the motor after that initial start which is kind of aggrevating and sometimes embarrasing! Should I lift the fast idle lever while starting?

 

[Dhadley]

Re: Electric fuel pump?

No need to advance the throttle, Quick Start will do that automaticaly. Just don't shift it until the motor comes out of Quick Start.

 

[rottenray]

Re: Electric fuel pump?

Thanks again!

 

[rottenray]

Re: Electric fuel pump?

I wanted to post one more reply to give everyone an update.
Last weekend I unhooked the fuel line at the in line filter under the motor cowling and found the entire line and filter full of oil. I figured this was what you said Wilde1j about the diaphram having a small hole in it. A new pump was $400 so I unhooked the VRO system and premixed the tank of fuel. Took it out and it still had a hard start because there was a lot of oil still in carbs and system. Once started it ran fine.
This weekend was the real test.. I installed new plugs and took it to the launch ramp. It started like it should and the quick start seems to be working because I didn't raise the fast idle lever but the engine fast idled and then idled down by itself and ran great. SO once again thanks all for your help and I think that the problem is solved. A side benefit of premixing is I can now run my kicker motor off of the main tank!