Johnson 70hp starting issue

Desertau

Steelhead
I writing this ahead of knowing if I’ve fixed this or not, hopefully when I get the chance to put it in the water it fires up and I can go through all the steps outlined in the service manual I just purchased, like properly syncing the carbs, setting the idle screw, checking timing and spark advance and there may be more but I’ll follow the book ($100 used) as best I can it uses fairly technical terms but backs them up with images so it will just require rereading and following step by step… if it runs. I’m a little unclear writing this but the sea foam was before the kill switch bump blowing the fuse.

It’s had issues idling at no throttle coming into the dock the engine shutting down making docking a little tricky but I’ve managed it going as slow as I can and using my boat hook. The plugs are new gapped to specs as are the filters and it runs great (or did) other than that idle issue. Figuring I’d try the easiest thing first I dumped a 2oz fuel to gallon ratio of marine sea foam additive into the tank and things seemed to be ok, stable at least. The boat sat in dry storage for a little over a week and putting itin the water it would not start. Plugs Had good spark turned over fine it should have run.

The plugs all are new, correct type gapped to factory specs, but trailering it my knee bumped the safety shut down killing the engine so I just paddled it onto the trailer. I checked the main fuse and it had blown, I got new 20 amp fuses and next trip out it wouldn’t start. I checked Spark that was fine, so maybe fuel gunk from the sea foam treatment, the oil reserve was 1/2 full. I took it home and started checking fuel starting at the tank, filters, fuel lines, choke solenoid everything was OK. I’ve replaced the fuel line and primming bulb (factory part), pulled all 3 carbs disassembled removed jets soaked everything 24hrs in parts cleaner and blew it all out with my air compressor put it back together and noticed a little fuel leak at the T to the choke solenoid so I removed the fuel manifold assembly and put all new heavier zip ties and plugged the fuel line ends connecting it to my bicycle pump with that assembly submerged in water pressurized it making adjustments until there was no bubbles any where the problem spot was the T. I’ve ordered 6 feet of new marine grade 5/32 fuel line and brass fuel manifold and I’ll use a brass T but I’m still waiting for that stuff, but my temporary fix should be good short term? I hope it will idle better now after the other adjustments the carbs looked pretty good so I’m not really sure what was going on, compression tested good when I bought the boat. The safety shut down and starter solenoid were intermittent I’d already put in a new ignition switch. Guess I’m really just preparing for the next steps and wondering what I’ve missed? What do you all think I should focus on?
Thank you
 
Figured I’d give it a crank before dropping it off in dry storage and good news it fired right up, I only let it go a half second because no water but it fired!
 
Two stroke? Four stroke? Non alcohol fuel?
Two stroke AVO, last fill up was the marina non alcohol fuel where fuel with alcohol was used it was followed with a treatment product to deal with alcohol. According to the service manual some small amount of alcohol is permissible but off the top of my head I don’t remember the exact amount, this morning I don’t have time to look it up but I’ll post that information from the service manual for that engine and that year later in case procedures have changed since 1997?
 
Ok thank you for replying I had surgery this morning sucks getting old, so please excuse my lack of manners. So I try to go with non alcohol fuels but the marina when I asked them didn’t know or at least the guy manning the pump didn’t so I had to just assume they would use non alcohol fuels at the fuel dock? But I have no way of knowing for certain, I think if they don’t there would be issues with a lot of boats on lake Meade.

This is what the service manual says about acceptable fuels;IMG_5572.jpeg
Replace the fuel pump yet?
no not yet, I spent 4 years throwing parts into my Jeep after having a shop I’d trusted putting in a new stroker engine give it back to me with a host of issues so I figured I’d take a different approach on this boat. I did take the fuel pump loose and the lines looked ok but not having the fitted lines on hand all I checked was that it was pumping fuel.
 
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