Starting in cold weather

[BigTerp]

Had trouble over the weekend getting my 1994 50/35 Johnson Jet to start. It was about 4 degrees out that morning and she just didn't want to turn over. Tried everything from holding the choke in, opening up the fast idle lever, etc. We eventually got it started (after a good 20 minutes or so) and once warmed up everything seemed fine. I use fresh 93 octane gas with marine stabil in every tank and am currently running 36:1 gas/oil ratio. The engine has about 13 hours on it since a complete rebuild. Being barely out of the break in period and in the dead of winter we've keep the gas/oil ratio at 36:1. Anything I'm doing wrong that caused my starting issues in the cold weather? Any suggestions to keep this from happening again?

 

[JMichael]

Increasing octane lowers how easy/quickly a fuel detonates so I would try using regular/lower octane and leave the stabil out since you're using fresh gas.

 

[BigTerp]

JMichael » Today, 10:58 am[/url]"]Increasing octane lowers how easy/quickly a fuel detonates so I would try using regular/lower octane and leave the stabil out since you're using fresh gas.

Thanks!! I've heard about lower octance detonating better/quicker, so that may be the ticket. I'm running 93 octane because my manual encourages it. Would I be suffering if I use lower octane fuel? When I say fresh fuel, I'm talking within a week, 2 weeks max. Doesn't the stabil help with the ethanol issues regardless of fresh fuel or not?

 

[user 6672]

I followed your rebuild..

whens the last time you changed plugs? Runnning that rich can/will foul them out quickly.

As for the octane.. id try to do a little more research on that.. i got my old TOP 115 merc and run 87 octane in it all day.. I just keep the timing down to prevent detonation..

on a side note once she was running you notice her have a bit more "ummphh" in the colder air? Mine loves cold fall and spring days..

 

[Captain Ahab]

Stop running the boat in such cold weather - or move someplace warm

 

[BigTerp]

Canoeman » Yesterday, 5:48 pm[/url]"]I followed your rebuild..

whens the last time you changed plugs? Runnning that rich can/will foul them out quickly.

As for the octane.. id try to do a little more research on that.. i got my old TOP 115 merc and run 87 octane in it all day.. I just keep the timing down to prevent detonation..

on a side note once she was running you notice her have a bit more "ummphh" in the colder air? Mine loves cold fall and spring days..

We changed plugs that morning, didn't seem to make a difference. The plugs we took out did look a bit wet, but they weren't terrible. The motor has been running so well with the current oil/gas ratio we haven't leaned it out any. Something I should consider doing? Get it closer to 50:1 maybe?

I just installed a tachometer recently. Once the weather gets out of the single digits we are going to work on fine tunning the motor now that we can read rpms.

I can't say I noticed any difference. The weight I have in the boat seems to vary each time I have it out depending on who/how many goes hunting with me. And the weight I've put on since the holidays doesn't help any either!!

 

[BigTerp]

Captain Ahab » Yesterday, 5:53 pm[/url]"]Stop running the boat in such cold weather - or move someplace warm

I hear BassAddict lives where it is warm.................I'll stay where I'm at!!!

 

[ShadowWalker]

This might sound dumb, but is it possible that parts of the pump were freezing? Would make it harder to start.

 

[PGRChaplain]

Why are you running a 50:1 motor ay 36:1? That along with the 93 Octane fuel won't hardly burn with a match. Try 50:1 with Regular 87 octane and see if that works better. Also 2 Stroke motors don't want to start when it's Cold out!

 

[user 6672]

My auger and snow blower have no problems starting at -10.. dont see 8 degs as an issue here..

 

[BigTerp]

PGRChaplain » Yesterday, 5:27 pm[/url]"]Why are you running a 50:1 motor ay 36:1? That along with the 93 Octane fuel won't hardly burn with a match. Try 50:1 with Regular 87 octane and see if that works better. Also 2 Stroke motors don't want to start when it's Cold out!

Because it's barely out of the break in period. Calls for 25:1 during break in. We've leaned it out to 36:1 and the plugs at WOT look spectacular, which is why we are keeping it at 36:1. The motor is, however, running rich at idle, but we adjusted that this past Saturday when it was out. My manual also suggests 93 octane. So there is where the 36:1 and 93 octane combo. comes from. It started up and ran fine this past Saturday when it was in the 20's. Might just be one of those things with this motor when the temp gets down close to zero. When that happens I'll give regular octance gas a try. Thanks for all the help!!

 

[BigTerp]

ShadowWalker » Yesterday, 5:07 pm[/url]"]This might sound dumb, but is it possible that parts of the pump were freezing? Would make it harder to start.

It's possible, but I don't think that was the case. My pump sits pretty far down in the water when the boat is at rest. I'm thinking the cold + wet plugs made it difficult to get started. I'm sure the motor sat around idling while my buddy was getting the truck/trailer ready the last time we had it out. Those wet plugs sat all week until we took it out again at 4 degrees. We've since fixed the running rich at idle issue, so hopefully that'll help.

 

[ShadowWalker]

Just a thought, you didn't really specify if it was the first start in the morning, or just any start throughout the morning, etc.

I don't have a jet, but first thing in the morning the shaft on my mud motor is frozen. It did't want to turn over, and if it did, it would be too slow to start. I have to give the prop a couple spins by hand before I put it in the water, and it will fire up all day long. This is where my frozen pump though came from, figuring moving parts that were in the water aren't for a day or two at a time, and could freeze.

 

[turbotodd]

Not familiar with the motor, but all engines suffer from cold weather starting to an extent. Some worse than others, and there are tons of variables.

Fuel is the #1 issue. 2 weeks is all we are getting before the motor gets hard to start (or won't start at all in some cases). I've verified this with my own motor. 10 days is all the older the fuel was last time I was out. It started and ran, but would not accelerate for anything. It would run at idle and just off idle, and wide open and nothing in between (just bogged). Thinking it was fuel related I pulled the fuel line, ran it dry, and then loaded it up and headed to the gas station (5 minutes away). Filled up with new 87 octane and tried it again. Ran perfect.

It's been my experience that sta-bil type products don't help much. The fuel evaporates and leaves stuff behind that won't evaporate, then it becomes concentrated with those additives (whatever they are). And the motor won't run right. All fuel since about 2008 has been formulated specifically for EFI cars and trucks that don't sit for any period of time. And it gets "old" quickly-especially winter blended fuel. I quit using sta-bil and just either use up the fuel I have, or tump it into the car when I'm done running the boat motor for the day. If I know I'm going back the next day I'll leave it, but most of the time I never know when I'm gonna get to go again.

Not saying it's your issue, but I felt it was worth mentioning.

Do the choke butterflies close completely?

 

[Triple obsession]

BigTerp » 07 Jan 2014, 10:19[/url]"]Had trouble over the weekend getting my 1994 50/35 Johnson Jet to start. It was about 4 degrees out that morning and she just didn't want to turn over.

By turning over do you mean cranking speed with the electric start? If so it wouldn't hurt to check the batt with a volt meter before you try to crank it. If it's not fully charged, (around 12.8 volts) it will crank slower & that can make it hard to start when it's that cold.

Also, 2 stroke oils have come a long way in the past 20 years....don't be afraid to mix @ 50:1 using a quality oil.
If I told you what ratio I mix some of my stuff at you'd probably crap you pants :lol:

Cheers
Gary

 

[BigTerp]

ShadowWalker » January 14th, 2014, 1:14 am[/url]"]Just a thought, you didn't really specify if it was the first start in the morning, or just any start throughout the morning, etc.

I don't have a jet, but first thing in the morning the shaft on my mud motor is frozen. It did't want to turn over, and if it did, it would be too slow to start. I have to give the prop a couple spins by hand before I put it in the water, and it will fire up all day long. This is where my frozen pump though came from, figuring moving parts that were in the water aren't for a day or two at a time, and could freeze.

It was the first several starts in the morning. Ran crappy for the first few minutes once we did get it started. After that the rest of the day was fine. You may be on to something though.

 

[BigTerp]

turbotodd » Yesterday, 9:16 pm[/url]"]Not familiar with the motor, but all engines suffer from cold weather starting to an extent. Some worse than others, and there are tons of variables.

Fuel is the #1 issue. 2 weeks is all we are getting before the motor gets hard to start (or won't start at all in some cases). I've verified this with my own motor. 10 days is all the older the fuel was last time I was out. It started and ran, but would not accelerate for anything. It would run at idle and just off idle, and wide open and nothing in between (just bogged). Thinking it was fuel related I pulled the fuel line, ran it dry, and then loaded it up and headed to the gas station (5 minutes away). Filled up with new 87 octane and tried it again. Ran perfect.

It's been my experience that sta-bil type products don't help much. The fuel evaporates and leaves stuff behind that won't evaporate, then it becomes concentrated with those additives (whatever they are). And the motor won't run right. All fuel since about 2008 has been formulated specifically for EFI cars and trucks that don't sit for any period of time. And it gets "old" quickly-especially winter blended fuel. I quit using sta-bil and just either use up the fuel I have, or tump it into the car when I'm done running the boat motor for the day. If I know I'm going back the next day I'll leave it, but most of the time I never know when I'm gonna get to go again.

Not saying it's your issue, but I felt it was worth mentioning.

Do the choke butterflies close completely?

Yeah, the choke mechanism works well. As far as I can tell at least. I understand what your saying, but doesn't stabil type additives help curb the problems associated with ethanol blended fuels no matter if the fuel is fresh or going to be sitting for awhile?

Haven't had any problems since that really cold morning. We will have it out tomorrow, Saturday and Monday. Will be a good test to see how everything runs.

 

[muddywaders]

Not familiar with Johnson 50's but it may have a nuetral throttle stop that prevents it from over revving in nuetral. It may be possible to
adjust or disable this feature to allow more air/fuel into the engine-this worked on my Yamaha.Be careful though as this makes it easy to flood.
Do not use fuel with ethanol.Hope this helps mw

 

[Pappy]

Lets clear some things up here.
Running 36:1 fuel/oil ratio in your engine is great! No, it will not foul plugs easier. You can run 24:1 all day long in those engines and never foul a plug.
I currently run 16:1 in my old opposed twins that have nowhere near the spark energy of the capacitive discharge systems of current engines and never foul a plug.
During break-in I can and will go as low as 9:1 on the old monsters and they will still run.
Plug fouling simply will not happen with a functioning modern ignition system and a properly adjusted carburetor.
One of your early replies was pretty much on target steering you to a lower octane fuel. The other thing that may have been needed that day was a fuel with higher aromatics in it or a good "Winter Blend" fuel. That fuel may not stay fresh for as long but I have very little experience with those blends in Northern climates and will differ to those who have local knowledge of them as far as their storage capabilities.
The wives tales of plug fouling are just that...........keep doing what you are doing and your engine will outlast many that are run on 50:1. You have more oil there as protection from metal to metal contact plus during an overheat that extra oil is worth its weight in gold in protection.

 

[BigTerp]

Thanks Pappy.

You basically reiterated what my buddy was telling me about the engine. He is a mechanical engineer and actually did the rebuild on this engine over the summer. I was suggesting we lean out the gasil ratio, but he explained to me why we are keeping it at 36:1. We have the carbs adjusted properly now as well, and last time out the motor ran really well.