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Proper Steps to Start Engine After Long Storage

J

Jim Zimmerman

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I have a Merc 4.3 Alpha i/o th

I have a Merc 4.3 Alpha i/o that hasn't been started in a couple of seasons. It was winterized b/4 storage but I don't want to kill my motor. Sooooooo ... I need some help in the proper steps to bring it back to life. What I found so far is the following:

1) Replace Battery
2) Squirt penetrating oil into each cylinder and let it sit overnight
3) Replace oil / filter
4) Siphon out old gas and replace with new gas & gas filter
5) Change plugs
6) Hand crank motor to make sure it isn't frozen and to lube block
7) If frozen repeat step 2

I also read that I needed to replace the head gaskets and all belts but that seems a little much.

Opening day of boating in Seattle is SAT so any and all help would be greatly appreciated.
 
"Disconnect the coil when hand

"Disconnect the coil when hand cranking. If it hand cranks, w/coil wire grounded, connect the muffs w/water running and crank the engine 10-20 seconds at most to build up oil pressure. Repeat after letting the starter cool for 30 minutes. No need for gaskets but new belts would be good. Change ALL fuel filters and add a pint of SEAFOAM to the fuel tank before adding fresh fuel. Replace spark plugs if dirty.

When was the OD impeller last changed? It should probably be changed due to dry rot. Was the OD oil changed? Check it and the level at the vent screw. Running on muffs will not tell you if it is pumping water; the hose is pressurizing the cooling system."
 
"You may first want to turn it

"You may first want to turn it over a rev or so with a socket on the damper pulley nut, just to get it moving.

Then cranking it over using the starter with the plugs removed makes it easier to circulate the oil. BE careful with any sparks as you are pumping combustible air-gas mixture out the plugs holes while doing this.
Best to disconnect the coil primary or ground out the high tension lead as Guy says.

You should get 10 psig or so on your oil pressure gauge within a short while of cranking. Do this a couple of times to be sure you are getting fresh oil to all metal to metal contact areas. Critical for the camshaft lobes which are only oiled by rundown from the lifters.

Check the belts for fraying and/or cracking and judge accordingly.

Rod"
 
"Great advice ... I got the ne

"Great advice ... I got the new battery and leads installed today, penetrating oil in the cylinders soaking, the complete part kit to replace the impeller, hand pumps to drain and then replace the engine oil / gasoline / lower unit unit oil, the seafoam, and new plugs. About $300 bucks in parts / supplies so far but much cheaper than a new engine.

I'm getting excited about bringing my baby back to life as I bought it new and I've used it a lot for 16 out of 18 years. It's almost becoming a classic now as it's a deep V with a lot of teak so I just gotta keep it. Wish me luck tomorrow!!!"
 
we have engines sitting down h

we have engines sitting down here for 2 years at a time. We charge the battery and start if right up. But our climate is better than where you live so that may make a difference.
 
"As always it takes longer tha

"As always it takes longer than you think ...I couldn't get the oil siphon started (needs to be warm oil I believe), had to draw the gas out from underneath the floorboards and I had 20 gallons in it, and then when I'm ready to crank w/o plugs NOTHING !!! One nuance I always had is the bow up trim will not lift the motor if the battery is even slightly low (and it's brand new) so if it was off to trouble shooting.

The ground wire got really hot and I'm going to replace that next. I kept the charger on low charge overnight and if that doesn't do it next on the list would be the starter but I am very open to comments !!! As an FYI, it hand cranks over and the belts stayed in great shape."
 
Check both ends of both trim p

Check both ends of both trim pump wires. Clean and tighten them and the new battery terminal points.
 
I'm having the same issue,except boat motor turns over well battery is fine but will not start it fires sometimes.

Squirt a bit of gas into the carb and see if it wants to start- if it does, the fuel isn't reaching the carb or the bowl is empty (if it has a carb). If it's injected, you'll need to check the fuel pressure.
 
Jim.... What do you mean by "it was PROPERLY winterized"? Do you KNOW it was? Cause an engine PROPERLY prepped for long term storage will start right up after hooking up a nice fresh battery. The gas was treated before storage. Oil was put into each cylinder, the lower unit oil was changed, engine oil was changed. ETC. My outboards and inboards needed nothing more than a charged battery to start after long term storage. .... because they were all properly prepped for long term storage.

If you suspect it might not have been properly stored I would drain out the gas and replace, change all the fluids, pop off the plugs and inject oil in there and hand crank with the battery cables off. Start it up with fresh non-ethanol gas.
 
"As always it takes longer tha

"As always it takes longer than you think ...I couldn't get the oil siphon started (needs to be warm oil I believe), had to draw the gas out from underneath the floorboards and I had 20 gallons in it, and then when I'm ready to crank w/o plugs NOTHING !!! One nuance I always had is the bow up trim will not lift the motor if the battery is even slightly low (and it's brand new) so if it was off to trouble shooting.

The ground wire got really hot and I'm going to replace that next. I kept the charger on low charge overnight and if that doesn't do it next on the list would be the starter but I am very open to comments !!! As an FYI, it hand cranks over and the belts stayed in great shape."

You used wrench-tightened non-Nylock or wing nuts for the battery cables, right? Nylock can lose their grip and wing nuts aren't approved by the Coast Guard anymore because 'finger-tight' isn't good enough.

Measure the voltage AT the battery while you crank the engine- if it stays around 10VDC, you may be OP, but if it drops significantly lower, find out why- have the battery load tested, even if it's new. If that's OK, measure the cranking voltage on the red and black cables, independently- connect one lead to the positive battery post and the other lead to the starter's positive terminal, then repeat with the black cable. If you see a significant voltage drop, you probably need a new cable. You may even see a fairly large voltage if you connect one lead to the battery post and the other to the cable after its connection to the ring terminal- that means your cranking voltage will be lower than required and the current will be higher. The Current capacity of a conductor is directly proportionate to the cross-sectional area of the conductor, which is the reason for heavy cable. The connecting points require this, too- a loose nut with a star or lock washer means that only the edges of the washer where it's split or the little tabs on the star washer are in contact and that means the current is trying to be conducted by very little material.

The battery posts are ALWAYS the reference points, not the cable clamps, nuts, distribution blocks, etc. ALL connections conduct to the load and if they have some kind of defect, the voltage will drop and current will rise if the device being powered is to work as designed.

If a starter comes with a test data sheet, it should show the current used while cranking and the Power, in Watts or Joules. If the power is expected to remain relatively constant, decreased Voltage requires more Current P=IE demands it and even a gear reduction starter like the ones on car/truck engines will need more than 300 Amperes (IIRC, the sheet showed ~4200W). The one for my Mercruiser 120 tested at about 350A, the starter on a larger engine will use more because the engine provides more resistance to cranking.

If the battery cables near the ends are noticeably stiffer than in the middle, they may have thermal damage or if the boat has had a vented battery, fumes from the electrolyte may have attacked the Copper. If you bend the cables and hear crunching, they should be replaced, based on my experience, anyway.
 
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