mid 70s Evinrude 85 starts easily in driveway, bear on the lake

[heckhole]

Have a mid 70s Evinrude 85hp that starts like a champ in the driveway, turns over for a second or two and fires.

Get it on the lake and the fun begins. It'll turn over fine, motor, sounds like it's about to catch and the starter gear disengages and the motor doesn't start. The starter appears to operate correctly, the motor acts for half a second like it's about to fire and the starter disengages but you can hear it spinning freely. It will take 10-15 attempts and it behaves the same way until you get lucky and it'll start right up. Once it has ran in water it generally starts in the first 5 tries, occasionally it'll start right up for a couple trips once it's been started at the ramp.

Doesn't matter how I trim the motor at the ramp, it will not start without 20 minutes of playing games. Once she runs, it's a fast, smooth, great running outboard. Never hiccups, never dies when idling or putting around.

 

[heckhole]

I should mention that the boat hits 40mph easily, I forget my compression readings but they were high and all cyls were within 1-2psi, hit and cold. If I remember correctly they were all well over 140psi. I forget the exact number.

 

[oldboat1]

need a strong battery, fully charged. Starter disengages when engine pops -- guessing the sound you hear is the bendix gear retracting down the shaft. If the starter is spinning freely with key switch but not engaging, different issue. Think I would start by shining up all connections, and making sure the battery is strong. It may be time for a starter rebuild. Motor in the lake will have more back pressure than running on muffs.

 

[GA_Boater]

What is your starting procedure when cold?

 

[heckhole]

After I typed this out, I started thinking maybe my battery doesn't have enough cranking amps.

The starter always engages when trying, it's when the motor tries to chug for that 10th of a second to start when it disengages and spins freely.

My cold start procedure on the lake? Well I live 5 minutes from the lake. I always start the boat at home on muffs. Doesn't need any choke, just needs lever lifted halfway. When I get to the lake I've tried full lift, half lift, choke switch while trying the first 20 times, I've tried none, half, full, choke, no choke on different trips. Nothing has made a difference. When I get it to finally fire on the lake, I've had it choked or not choked with the lever in all positions, it'll start in any of those methods, just getting it to crank long enough seems to be an issue?

If the motor fires at all, it will never shut off on me. Only with the key!

I just want to clarify, when the motor does sound like it's ready to pop, the starter gear does spin freely and I have to try all over again.

Last season I had issues with the key not engaging the starter and it ended up being the neutral safety switch being worn. I had to reposition it a little in the control box and solved it.

 

[GA_Boater]

You didn't mention squeezing the bulb to fill the carb bowls.

 

[heckhole]

My bad. That's part of the procedure too lol.

 

[racerone]

Does the timer base rotate when you lift the fast idle lever , yes or no ?

 

[heckhole]

I've never noticed. I will check.

 

[oldboat1]

when checking:

I used to routinely cold start my 85 (’'70) using the manual choke —-- just reached back and disengaged the choke when the motor fired. Possible your auto choke isn’t working. Also, that neutral start switch could be an issue again, if the starter seems to periodically disengage on it’s own when trying to start. Could be the switch, or a connection issue, or positioning again as mentioned earlier.

And if you have a known good battery with solid cca, might just substitute it to see if there is a difference down at the lake.

 

[emdsapmgr]

My 79 85 hp crossflow is very sensitive to the choke. Barely need to push in on the key switch when cranking- and it's running. If I push in too long, it will flood. If you don't have a working choke, however, these are a bear to start cold. Not sure if you said you watches the choke butterflys close when the key is pushed in. On these older ones, you can mis-adjust the piston and may not know if the choke butterflys actually close fully or not.

 

[heckhole]

I have a separate choke switch, my key is not push to choke. I can verify the butterflys fully choke.

The fact that it starts 100% of the time out of water would indicate to me that the neutral safety switch is functioning.

The starter gear will sit there spinning after its disengaged from the motor for as long as I hold the key in start position. When my neutral safety switch failed, I could only get accessory power and could not get any reaction from the starter.

 

[heckhole]

I think I will bring a battery booster to the ramp with me and give that a shot. I have noticed if I have a tailwind and the boat is moving forward, it will fire right up. We would joke that it needs a bump start.

 

[heckhole]

Does the timer base rotate when you lift the fast idle lever , yes or no ?

Timer base does rotate with the idle lever. Very smoothly.

 

[heckhole]

And if you have a known good battery with solid cca, might just substitute it to see if there is a difference down at the lake.

What should I have for cold cranking amps? I have used this battery to start a Yamaha 90 and a Force 125.

 

[boobie]

When it won't start, have you checked your spark with an open air gap spark tester set at 7/16 " ??

 

[oldboat1]

My choice would be in the range of 700 cold cranking amps. It's the condition of the battery, though. If your starter is turning it should be kicking the bendix gear up into the flywheel, not (as you describe) spinning on the shaft. You may be due for a starter rebuild and/or a new battery. It's not worth fooling around with, in my view -- would just replace the battery if it's more than two or three years old (at least have it tested). If the battery tests good or is replaced, pull the starter and have it tested (rebuild or replace as needed -- depends a little on resources where you are. At one time, I was on a first name basis with a little old fashioned starter/alternator shop. Important to find one that does marine starters.) Got to believe you have a battery or starter problem, easy to solve.

 

[Fed]

Your bendix is doing exactly what it's supposed to do, there's no reason for the gear to rise up the shaft if it's spinning at the same speed as the shaft, in fact the spring will keep it pushed down.

Sounds like your getting an initial half hearted pop but then the motor is not continuing to run.

Has it ever worked for you trouble free in the water?
Is this something new that has started happening?
Sounds like flooding combined with the extra back pressure to me.

 

[oldboat1]

I have a separate choke switch, my key is not push to choke. I can verify the butterflys fully choke.

The fact that it starts 100% of the time out of water would indicate to me that the neutral safety switch is functioning.

The starter gear will sit there spinning after its disengaged from the motor for as long as I hold the key in start position. When my neutral safety switch failed, I could only get accessory power and could not get any reaction from the starter.

bendix spinning but not engaging, with the key in the start position -- looks like an issue. Could mean in the run position, I guess, with the gear vibrating on the stationary starter shaft. Will stick with battery/starter issue and check back for progress.

 

[heckhole]

I don't have a spark tester unfortunately. I'm just a semi-mechanically at-home inclined chump. Lol

This has always been a bit of an issue. More so this year than last. It does sound like the battery turns the motor over slower than past.

I believe the CCA is 650 on my battery.

Now you guys have me excited it may be something simple. I have a friend who can rebuild the starter if need be. I will bring my booster with me and see if that helps. I'd rather not throw a battery at the boat ($150) if I need that money for a starter rebuild. If there is one thing I hate doing - it's throwing money at my boat. I spent 40 on trim relays when it turned out to be a 3 dollar sealed fuse that tested good but couldn't handle a load and a day of melting in the sun!

Excellent resource here. Thank you.