• This site contains eBay affiliate links for which Sea-Doo Forum may be compensated.

Bad starter or not enough battery/amps to turn rebuilt engine?

mini4mw

New Member
Hey all. I've rebuilt a 2005 RXT 1503 4tec. (new rods, pistons, rings, bearings, heads machines, cylinders honed, valves lapped, spark and other misc parts) I've rebuilt a few SxS engines, but first SeaDoo. Pistons were a little tight, but I could still rotate the crank with a breaker bar and thought I'd be all good. I've got everything back together, however, if the spark plugs are in I get less than a full rotation when I try to start. Hit start and I get a 1/3 rotation and stop. Take the spark plugs out and she turns over fine 5+ seconds until I let go of the start button. The compression stroke blows a towel up on spark plug hole when they are not in. I pulled jet pump (it was rebuilt as well with new bearing/prop/ring and is a little hard to turn as well) and pulled the hose for the SC to reduce compression. Same issue. Hooked up battery jump and separately tried jumping off my truck, same issue. Put some oil down the spark hole and it turned over a little easier, sometimes 2/3 rotation instead of 1/3 (with sparks in). I tried one spark plug and it still only made it 1/3 a turn. Sometimes after a failed start the dash resets like it had no juice and was then plugged in to a battery. I'm pretty sure if I could get it turning it will start.

I'm going to charge the jump pack, perhaps use a car battery use jumper cables to terminal leads on the RXT in a few days ( I don't have it at the house). That should at least eliminate the battery issue. If it still won't turn over, do you think replacing the starter will fix? It appears to be the original starter (bought RXT used) Man, I hate to think of tearing this thing up again to get at that starter.. it was such a pain removing and installing the engine, electrical and hoses.. Too much compression may be causing need for extra power for turning over, but there's not much I can do about that...

So I suppose the question is, if I double up on battery (jump pack and car battery to get her going, parallel for high amps at 12v) and it still wont turn over with spark plugs in, do you think its just a worn out starter? Before I got it, it did turn over but wouldn't start; rings had rusted in piston and coolant was in the oil, 20 psi on each cylinder. It had gouges from piston ring impact on the head and had been rebuilt. Guessing the head was not machined and caused the leak as the intercooler and oil cooler are not leaking and head gasket looked ok to the eye, it just may not have been sitting flat enough due to previous damage.

Any other ideas besides rebuilding starter/buying a new one? If the compression is high, is it possible an old starter doesn't have the juice? It had 230hrs on it if I remember correctly. I also rebuilt the SC and its in good shape.

thanks-
 
ok, tried out a new battery and it turned over fine today. Didn't start, but turned over with sparks in.

Old (new) battery was 20ah, ~300cca. New one is 30ah, 385cca. The jump pack itself worked fine this time after charging up as well. Not sure why the jump didn't work unless I needed to leave it on the jetski battery to charge. Perhaps it just didn't have enough cca.

New battery is Diehard from Advanced Auto Parts:
DHPWO Battery: TX30L Group Size, 385 CCA, 30 Amp Hour Capacity, For Off-Road Use
Part # TX30LA

As for the not starting, fuel pump is not kicking in. Tracked it down to wires inside the tank to the fuel pump motor itself or the fuel pump motor. Strange one I'm still working on figuring out.
 
Back
Top