Starting a dormant boat - advice needed

armchairsailor

armchairsailor

Well-Known Member
Joined
17 Sep 2009
Messages
1,144
Location
back aground in Blighty
Visit site
Hello all. My first post in this forum I think... As a newbie to power boats I'm not really experienced in even starting them, so I thought someone might be able to give me some pilot notes, so to speak.

Tonight I decided to have a go at starting my old Sangster 18 project - it's a locally made 1979 vintage deep V speedboat with I/O 140hp mercruiser in the back. The thing has sat since i got it 2 1/2 years ago, so I'm not expecting it to fire up straight away at all! I was assured the thing was a runner when I got it, so it's time to see if it's true. My intention is to find out if the engine can actually run, and if so, then fog it up so I can remove it to rebuild the rotten transom, so this is the first step in saving it from a landfill. It would be nice if this wasn't a "do not pass go" project.

Batteries were sufficiently charged to light the navs, power the leg, run the blower and all that when the key is switched to the first notch. I turn the key to start and get the starter solenoid clicking but that's it. The ammeter shows nothing - even when hooked up to my diesel pickup, with its double battery setup.

I suspect the batteries are just completely pooched, given that it's been dormant for at least 3 years with no attention, but all the other electrics work, and it was being boosted by the truck, so I expected the ammeter to show something. I'll try and get a voltmeter tomorrow to check them, but could it be something else? I previously replaced the ignition switch from a 3 terminal one to a 4 terminal (4th being for accessories) so may have cocked something up there, despite carefully swapping the wires; but then the starter did click...

I'd appreciate any advice you might be able to give.

Thanks!
 
Last edited:
You would be best served if you had a service done first! New fuel if 2 stroke,Carb cleaned, sump oil & petrol changed if not, Impeller changed, new plugs. Find someone local with Knowledge! Cause you will be really upset if you start and seize it first go! Best of luck.:encouragement:
 
petem said:
Also disconnect coil or whatever and turn over until you have oil pressure before firing it up.
Click to expand...

Thanks for the advice Quimby. I'd love to shell out the money on a service, but the object of the exercise is to see if it can actually turn over at all! I'm not willing to put a penny into this thing if the engine is seized. It was a free boat, so I'm not yet invested in it. It was previously run and oil pressure only showed when above a certain rev level, so I have been told it likely has a faulty oil pressure sender. Worst case, how long can you run an engine for before it seizes? 30 seconds? Less?

Petem: Thanks for the pointer on disconnecting the coil. May well do that as I can't get to the flywheel nut to manually rotate it.
 
Last edited:
Presumably a petrol engine.
Take the spark plugs out and see if the engine can be turned by hand .
 
I would remove the plugs then see if it will move. If so squirt some light oil e.g. 3 in 1 aerosol into the cylinders and then turn over several revolutions to get the oil all over the bores and pistons.

Remove the carb, fuel pump and fuel lines. Old petrol can turn into a thick gel so this will need clearing out.

Then fresh fuel and assuming it's 50:1 I would use 25:1 to get it thoroughly lubed up.

Fresh battery and see if it will go.
 
Also, many small boats were built with plywood box sections supporting the floor, or acting as hull stiffeners.
If the thickest piece of wood on the boat is rotten (the transom), then I'd also be poking around under the floor sections to get an idea of how big a job it's going to be.
 
You have not said what thickness of leads you used to connect your truck batteries you need fairly thick to avoid dropping the voltage, I presume you did not take them out of the truck just used a long jumper cable, perhaps you should connect a new battery directly, also check that the starter is free to turn the engine I would pull the plugs, squirt in a bit of diesel to loosen things up and then after a few hours soaking turn it over by hand, it should turn easily , next spin it up on battery be prepared for a spray of diesel out of the plug oles, connect up the plugs to the leads and look for a spark when somebody else turns the key. then put in the plugs and try for a start!!!

with regards to oil pressure spining it over with oput plugs should get some circulating and a short run to determine if it will start should be OK but dont rev it too much and check the relief valve or pressure sender/gauge
 
Last edited:
FlowerPower said:
Also, many small boats were built with plywood box sections supporting the floor, or acting as hull stiffeners.
If the thickest piece of wood on the boat is rotten (the transom), then I'd also be poking around under the floor sections to get an idea of how big a job it's going to be.
Click to expand...
Couldn't agree more. That's the underlying reason for the exercise: I need to remove the engine to assess the level of rot. It is solid fibreglass with longitudinal stringers, presumably 2x4 or similar. I'm looking into using Coosa boarder the transom repair, if it's not too expensive, and if the boat is worth the investment.
 
armchairsailor said:
Ouch. I've had other priorities to deal with: my life is pretty hectic.

Thanks for the advice. I'll certainly be soaking the cylinders as a starting point. Maybe even hook up one of the batteries if I can.
Click to expand...
Sorry it was harsh hope engine goes and rebuild too good luck
 
Sounds like it is a Mercruiser 4 cyl petrol which is a basic Chevy engine. So treat it like any simple automotive engine. It needs clean petrol and a spark to run. As suggested take the plugs out hook it up to a good battery and turn it over. If it is free, check for a spark with a plug at the block. If no spark then usual points/condenser/coil check.

Carb will almost certainly be bunged up with gunge and any auto shop will clean it out for you. Use a temporary supply of clean fuel as the tank will probably be contaminated as well. There will probably be a filter in the system somewhere as well. You should be able to get it to fire and run for a short while with these basic steps. However long term you need to look at the cooling system as it is likely saltwater cooled and this is the killer for these engines long term as they clog with salt and the exhaust header may corrode.
 
If you can't get at the crank pulley nut to turn the engine you may be able to turn it with the fan belt if the plugs are out. Can you put it in gear and turn via the prop? If the starter is easy to remove you could try a screwdriver on the flywheel teeth, and check the starter.
 
gordmac said:
If you can't get at the crank pulley nut to turn the engine you may be able to turn it with the fan belt if the plugs are out. Can you put it in gear and turn via the prop? If the starter is easy to remove you could try a screwdriver on the flywheel teeth, and check the starter.
Click to expand...

Thanks for the tips. May well try turning the engine via the prop. It's these hacks that have just passed me by.
 
So I got the chance to have a quick look at the engine tonight. I put it in gear and tried turning the prop. Nothing moved in forward, but it appeared to skip a bit in reverse and then it spun freely. I'm assuming that I've bust the shear pin! I'd forgotten about those things - shows how long I've been away from boats.

I also took out the plugs and looked inside the engine. Three of the four cylinders looked clean and dry, but one appeared to have rust residue inside. I squirted a good amount of storage seal oil into them, just for good measure. I'll try to turn it tomorrow via the fan belt. I doubt it'll turn but you never know. Maybe it's worth pouring some hot oil down that cylinder to try and free it, assuming it's stuck? Any ideas? I want to try and at make sure it isn't frozen solid before hailing the thing out. I can pull the head once it's in the garage.
 
So, had a look at the block today. There's a defined 4' line on the side of the block, below which there are lines of rust - to me that's a clear sign of the block being cracked. Apparently it's not uncommon with these 140s. It also appears that it may be fixable by using JB Weld ir some other metal/ epoxy concoction. I know it's a bit of a long shot, but well, what is there to lose? An hour or two cleaning it up, then fettling and sticking the goop on and hoping for the best. Better than forking out for either a new block or a new engine. The original intention for this thing was of spending the least amount of money possible to get on the water...
 
You must log in or register to reply here.

Share this page

Top