70 HP Evinrude issue, totally stumped

Hi

I have a 1980's 70 HP Evinrude OB that has a starting issue that no one seems to now how to address
When I intially try to start it, it cranks very slow and eventually it will fire
- after it runs for a while and has warmed up it will start with no problem

This is getting very frustrating at the dock while people are looking on to see this motor struggling to start

- battery is new 650 cca
- new ground cable
- alll connections have been cleaned
- starter has been checked and is ok

If i boost the battery it will turn over faster and fire

I am stumped

Re: 70 HP Evinrude issue, totally stumped

When I bought my new batt, I took a voltmeter with me and took the best one I could find. Granted Amps are what we need, but the volts did vary from about 12.6 to 12.9...guess which one I own?

Also, batts appreciate getting charged up before ever putting them in service. This may not help as much with a new battery as it does for that same battery a year or two down the road.

I also find that leaving the negative lead connected does draw it down, even when sitting. Take into account summer temps and a trickle charge will benefit you. My other powersports batts last 5 years...hoping my wet cell marine batt will, too, as long as I take care of it.

That's my take on the slow cranking.

I did read a possible "trick" to starting: Pump fuel line bulb until hard, Key on, push key in for about 8 seconds, after the 8-count keep key in and then crank it while idle throttle lever is raised.

You may need to repeat, but I've been happy with this procedure, overall.

Re: 70 HP Evinrude issue, totally stumped

PS...how did your old problem with the lower unit come out? I might be looking to do some work on mine sometime.

Re: 70 HP Evinrude issue, totally stumped

Walid1,
This is how I crank my 1983, 70 horse Johnson outboard and this is after I read the owners manual and I had alot of starting issues and flooding this motor when I first started using it and installed it on my pontoon boat.

When the motor is cold and the first start of the day, pump the fuel primer bulb up until hard, raise the fast idle/warm up lever all the way up, turn the key and hold it in for a few seconds, then advance the key to start and Walla!!! my motor starts the first time every time now doing it that way but as soon as it hits or fires over remember to bring the fast idle/warmup lever down until the tachometer reads about 1200 to 1300 rpms to allow it to warm up a bit, say about 2 minutes, then drop the warm up/fast idle lever down to its normal position which is all the way down. If I was you, I would get your new battery load tested just to be sure it is a good battery. I have had good brand new batteries be bad and have to get a replacement so make sure you take it back to the store you brought it from and have them load test it for you to make sure your new battery is good and not bad as sometimes they can be.

Re: 70 HP Evinrude issue, totally stumped

I see you replaced the ground cable, you might try a voltage drop test on the positive cable, maybe you have some internal resistance in it.