1978 Johnson V4 not starting on the ramp

[AAusbro51]

Motor Model: 85ML78C

I've had this boat since March and have not done anything to the internal motor, carbs.
I have replaced the plugs and compression tested the block. It checked out fine (about 106psi across all 4 cyl)
Fired up multiple times on muffs and has worked well. Motor is stored in the down position, as I heard leaving it in the tilted/trailering position isn't the best position for it.

I have tried to be on the water 3 times. First time out for a solo shake down w/ another boat was successful. The two more recent times.. with the family and all the gear.. unsuccessfully.

This most recent trip (Memorial Day) the morning of, I was able to fire the motor up in my driveway while on the muffs. Ran like a top & was able to shut off/start up like a dream. Packed up the family and headed to the water. On the launch ramp, my primer bulb would not get hard. It had gotten hard before, but not every time - and certainly not yesterday. After 50 or so pumps of the bulb while down in the water I figured I either had a faulty bulb or something else going on. After I gave up and pulled the boat up, I noticed quite a bit of fuel/oil mix draining down the side of the motor under the cowling and from the two small ports near the lower unit.

To add salt/vinegar/fire to the wound, yesterday after arriving back home, I decided to goose the starter to see what would happen... and darn it if that sucker didn't fire right up. I mean RIGHT UP. No choke - no bulb priming. Kissed the ignition and bam. I've never been blinded with fury as much as I was right then.

I have a feeling the bulb is working fine, but likely the needle/float isn't able to do it's job and needs rebuilt/cleaned.
I'm looking for confirmation of this - or ANY other ideas.
I have ordered 2 Sierra carb rebuild kits (minus the float). I have never rebuilt a carb, so this should be interesting (If anyone is in the Indianapolis area and would be willing to help..... I'm more than willing to talk about that. The boat is stored inside and have plenty of tools. Lowes and O'Riley is across the street, too.)
*end of total desperation plea*

To compound matters, I have a trip lined up to go to Dale Hollow this Saturday for a week and was really really counting on having this boat come along... obviously.

 

[interalian]

One thing to remember about priming bulbs: you should have the outlet end higher than the inlet. Certainly if it doesn't firm up when pumping that way, look inside the air silencer and see if fuel is coming out the carb vent hole(s). If so, yes, the needle isn't sealing. The more modern plastic floats are less likely to fail, but it's best to replace them while rebuilding.

I'd suggest you find an OMC Service Manual for your motor if you're planning to keep it and maintain it yourself - it's a great source for all the information and specs for your specific motor, unlike generic ones (Seloc...) that cover many years and are a bit sketchy on details.

 

[AAusbro51]

Any suggestions as to where I can track down a reliable source for this OMC service manual? Some of the searches I've done online look like they may be sketchy sources.

 

[interalian]

Eprey usually has original hard copies - that's where I got mine.

 

[AAusbro51]

What about something that would be electrically tilt-sensitive that would keep the motor from firing in the water on a launch ramp?

I am pretty sure I have a sticking float/needle. But that also means I should have 1 carb that is working fine. This motor fired up on the muffs earlier in the day. If I'm correct, with fuel - air - and spark, the motor should have at least given me a sputter?! - right? I know there is fuel getting to the carbs. The flywheel was cranking away. But it didn't fart-putter-fap or anything.

Maybe the bigger problem is electrical? Any thoughts on that concept? I'm not trying to put off a carb rebuild. Just trying to think this through and cover all my bases.

 

[ondarvr]

Frequently motor's will start much easier on muffs than in the water, the increased back pressure when submerged can hinder starting. Sometimes tilting the motor slightly, or not backing all the down the ramp can help it start quicker. It can also be your technique.

 

[AAusbro51]

Thanks ondarvr - Makes sense.
I could give not backing down as far a shot. I must say, after the two failed trips, I'm definitely looking at my technique as well.

Since it had fired earlier that AM, I didn't bother pumping the bulb at first - nor did I engage the choke. Cranked for about 7 seconds.
Pumped the primer a couple times and tried again for about 7 seconds.
Choked it and tried again for about 7 seconds.
Primed again with about 8 squeezes (didn't get hard)
Popped the cover and gave it a shot of starting fluid (I know I know... shouldn't do that... but I was desperate)
Choked it and tried again for about 7 seconds.

Ultimately pulled out of the water for about 20 minutes.

Repeated everything except for the starting fluid... The last go consisted of my 11yo daughter continually pumping the primer bulb while I choked and cranked the engine. After about 10 mins, I waived the white flag and pulled out and headed home w/ my tail between my legs and a grumpy wife & daughter.
Ugh...

Thoughts?

 

[ondarvr]

If you continue to pump the bulb the fuel has to go somewhere, and if you have a stuck or leaking needle valve it's going into the motor, which would flood it, continuing to pump will just make it worse. Starting fluid isn't great, but helps at times, it often won't work a flooded motor though.

​Pull out a plug and see if it's getting spark when you back it into the water.

 

[Silvertip]

Are you squeezing the primer bulb with the motor tilted? If so, you may be flooding the engine as the floats cannot shut off the flow of fuel. If the engine is in a proper state of tune then prime, engine tilted down or nearly down, fast idle lever 2/3 up, turn key to START while pushing in the key is the proper cold start procedure. Warm starts may or may not require fast idle use and generally no choke.

 

[AAusbro51]

I understand the bowls can't hold the fuel well w/ the motor tilted up. Primer bulb is only squeezed when the motor is down.
Also, I was noodling w/ the throttle lever, in neutral, between 1/3 and 2/3 throttle. I could of just been shaking a rubber chicken at the motor, because nothing seemed to make a difference.

 

[AAusbro51]

So, after reading more around our site, I learned that there may be some issues with the Atwood fuel line/bulb part kit. I purchased a new kit about 2 mo ago. Bulb hasn't been hard since the replacement. Took it back to WM and exchanged it today. Removed the air silencer cover so I could see the carb butterflies. Pumped the bulb probably 100 times to see where the fuel would leak from...... and no fuel showed up. (And the bulb never got hard)

The motor, however, fired right up on the muffs. No choke. First goose. Just buzzed right to life.

Is there really an issue with the WM Atwood fuel line?- and could that be my problem on the water/ramp?

Maybe the fuel I was seeing leaking out all over was the residue from the carb bowl contents sitting in the air silencer while trailering.

The plan is to leave the motor tilted up overnight and see how it fires up tomorrow afternoon. This should simulate being on the trailer, with dry bowls, on the way to the ramp. I will also raise up the front of the boat as high as I can to simulate the ramp.... best I can come up with aside from driving to a boat ramp again.

Any other thoughts?

 

[ondarvr]

While it's not uncommon for there to be problems with low cost hoses and bulbs, they don't know if your at home on the hose or on the water at the launch, they would typically malfunction in the same way at both times.

​Is the bulb being held with the arrow pointing up while you're squeezing it?

 

[racerone]

I can not believe you would squeeze the bulb 100 times without realizing something is wrong.--Should take no more than 5 / 8 squeezes !!----Check your entire fuel system from pick-up in the tank to fuel pump diaphragm.-Check the adjustment on the choke solenoid.-Does the choke solenoid click when activated ?-Going to sound like a broken record , but has a compression test been done ?

 

[AAusbro51]

Yes- arrow points to the motor.
The primer bulb never quite feels like it refills with fuel, so the 50+ pumps was pushing a tiny amount of fuel... I would assume the pressure would eventually increase, but it doesn't seem to suck any fuel back into the bulb from the tank (?)
First boat- trying my best with what I got.

I compression tested the motor a while ago. It registered about 96 across the board. (Misspoke on an earlier entry)
Choke/solonoid works.
Tried to look into the fuel tank, but could t see down to the pick up. It's 26 gal & full. Not sure how to test the diaphragm.. I see the fuel pump, but not sure if I should take it apart to inspect without the rebuild kit. Read that is a bit sensitive to disassembly. Not so?

 

[AAusbro51]

While it's not uncommon for there to be problems with low cost hoses and bulbs, they don't know if your at home on the hose or on the water at the launch, they would typically malfunction in the same way at both times.

​Is the bulb being held with the arrow pointing up while you're squeezing it?

I read the bulb should be higher than the tank... didn't know that the bulb should be actually held upright. Is that really the case?

 

[ondarvr]

I read the bulb should be higher than the tank... didn't know that the bulb should be actually held upright. Is that really the case?

​Height of the bulb doesn't make a difference, arrow pointing up does.

 

[Baylinerchuck]

If you disconnect the fuel line at the engine does the squeeze bulb primer pump fuel? If yes, plug the end of the fuel line. Does the bulb get tight when pumping? I have the same exact engine. I recommend NOT using Sierra carb kits. The OMC kits are much better. I had major issues with the Sierra kits, including gaskets that were too thick which upset the mixture from the main jet. I also eliminated the quick disconnect fuel connector on the motor as this was a source for fuel leaks.

 

[racerone]

Am OMC V-4 in good condition " starts right up "---------So inspection needs to be done !------Easy to put a new diaphragm in a pump.----My compression tester would show 120 on one of those.-------The starter needs to be taken apart for inspection too.-------Test with a " know to be good " portable tank and hose.--------Spend little time and $$$ to do inspection is always what I suggest.-------Some will argue that approach !

 

[AAusbro51]

Thanks again ondarvr - I'm going to have that arrow pointing upright from here on out. Since the bulb never got firm, and literally felt like I was pushing bubbles back and forth, that may be the real smoking gun. Maybe the residue I was seeing wasn't fuel. It was thicker than what I would think fuel would be. Maybe it's just build up from exhaust residue from the 40 years that unit has been in service.

racerone- thank you for the insight as well. I'll be getting into each of those things shortly just to be sure things are looking/working as they should.

Actually, my first attempt to take the family boating (Friday) ended because of a dead starter. When I hit the ignition, I could tell the flywheel wasn't getting the speed it needed. Triple checked voltage - ultimately it quit spinning at all. Solenoid would click & voltage was getting to the starter, but no go. Didn't even get to fussing with the primer bulb that trip. Got a new starter put on Sunday PM (thanks Amazon!) and it fired right up. Loaded the fam to go boating that next day. That was the morn of the squishy bulb.

I'll test again this afternoon and report back.
Crossing my fingers for a stiff bulb and immediate fire!

 

[AAusbro51]

Just got done with my test on the muffs again.

Simulating a trailer trip overnight with the motor tilted all the way up - Raising the boat as high as I could from the front end - dropping the motor down to it's lowest possible position - I cranked the engine but nothing happend. Empty carb bowls - as expected.
Pumped the attwood primer sideways and felt the squishy wimpy fuel swishing back and forth. This was where I had stopped on the boat ramp - because I didn't know the best position for the bulb was vertical.

So thats when the magic happened....

Held the arrow up towards the sky, gave the bulb about 4 good squeezes and it got stiff. **carb floats/needles doing their job!!**
Gave the ignition a go for about 3 seconds and Fat Betty (thats her name) roared to life.
No choke needed.

I think this info may help with folks that were fussing about the Attwood fuel line. Granted, it's a cheap system - but I'd bet that if 1/2 of them held the bulb vertically, it may have solved their issues as well.

I'm getting ready to head to Dale Hollow on Saturday for a week - so wish me luck and lots of fish. THANKS A MILLION to everyone that chimed in. Ondavar... I owe you a beer, my friend. Thanks for the tip!!