140 HP Seahorse won't start - start motor??

[madramire]

Model: JE140TLCRD

1984 model of Johnson Seahorse, has low compression in starboard cylinders but not too bad and was running fine.

Tried starting it up today to see if it is still in good nick - started fine for about 10 minutes, then died in neutral after about 60-90 seconds which is normal. I usually have to wait two minutes before starting again and she kicks in fine.

Only, this time, she didn't.

So, I done some troubleshooting - firstly, plenty of fuel in system and primed nicely, primed good too (bulb remained hard telling me diaphram is doing its job).

Secondly, checked charge in battery, 11.99 - so just a tad under 12, but the battery normally lies at 12.3 or so when she has run for a bit. So battery was okay.

Removed cover and checked wiring, nothing looking corroded or shorted - left cover off to check that start motor was engaging the flywheel properly.

This resulted in start motor starting, spinning and engaging the flywheel but not turning the wheel fully (1/4 turn or so and then dies, then 1/4 turn again and dies), so, it won't start.

The start motor then spins but won't rise to engage the fly wheel - is this a bad start motor or do I need to check the power head and Flywheel gear?

I am a novice at this and wonder if I shouldn't just leave it in for a good overhaul, engine was working fine back in early December on it's last run out.

I want to be able to repair and maintain this engine my self as I like working with the boat and have learned lots so far, so I am hoping that replacing the starter motor is the resolution.

Any ideas gentlemen??

thanks in advance.

Se?n.

 

[splitshot]

Re: 140 HP Seahorse won't start - start motor??

if the starter isnt rising to contact the flywheel, its either not getting enough power or something inside the starter is faulty...charge the battery and try it again if it does the same might be time to rebuild the starter...it kinda sounds like the flywheel is getting to the speed where it kicks the starter out, which is when the motor picks up and runs but your isnt running but its trying....what kind of compression numbers did it show ??

 

[Silvertip]

Re: 140 HP Seahorse won't start - start motor??

11.99 volts is essentially a dead battery and this is definitely NOT OK. A fully charged battery should measure 12.6 volts with no load. Your engine is exhibiting all the signs of a dead or weak battery. Try a "known good" battery. If that still presents a problem. Then using a single jumper cable, connect one end of the cable to the POS battery terminal and touch the other end to the large terminal on the starter motor. This will eliminate all the wiring between the battery and starter. If it now spins fine, you have a bad battery cable, corroded or bad terminal one of the cable or the other (or both), a bad solenoid, or a bad cable or connection between the solenoid and the starter. If it still doesn't spin, connect the other jumper cable to the negative terminal on the battery and an unpainted bolt or bracket on the engine block. Retry the positive jumper cable. If it now spins you have a back negative battery cable or connection. If it still doesn't spin, you have a bad starter.

 

[madramire]

Re: 140 HP Seahorse won't start - start motor??

80/100 was the compression in the cylinder and the other cylinder was 100/120.

The flywheel is not doing a full rev - it's turning a bit, and then it stops, to repeat before I let go of the key, takes about 5 - 8 seconds for it all.

 

[madramire]

Re: 140 HP Seahorse won't start - start motor??

11.99 volts is essentially a dead battery and this is definitely NOT OK. A fully charged battery should measure 12.6 volts with no load. Your engine is exhibiting all the signs of a dead or weak battery. Try a "known good" battery. If that still presents a problem. Then using a single jumper cable, connect one end of the cable to the POS battery terminal and touch the other end to the large terminal on the starter motor. This will eliminate all the wiring between the battery and starter. If it now spins fine, you have a bad battery cable, corroded or bad terminal one of the cable or the other (or both), a bad solenoid, or a bad cable or connection between the solenoid and the starter. If it still doesn't spin, connect the other jumper cable to the negative terminal on the battery and an unpainted bolt or bracket on the engine block. Retry the positive jumper cable. If it now spins you have a back negative battery cable or connection. If it still doesn't spin, you have a bad starter.

Gonna give the troubleshooting a go tomorrow and if it fails, gonna get a new deep cycle battery to see if that helps.

I have two batteries in the boat, but one is only for instruments and VHF, and it's not deepcycle. That has a charge of 12.5 volts while being used.

Thanks so far.

 

[splitshot]

Re: 140 HP Seahorse won't start - start motor??

you have a 40 lb difference from highest to lowest sounds like it wont be long before you have to go through that motor anyways

 

[madramire]

Re: 140 HP Seahorse won't start - start motor??

you have a 40 lb difference from highest to lowest sounds like it wont be long before you have to go through that motor anyways

I kind of figured that the powerhead was gonna need a good servicing soon enough alright, sounds like I might have to breka it down and check the cylinders for integrity and seals and so on.

Not a quick fix eh ah well, I have a while yet before the really good weather comes in, either that or I will try to trade it in soon for something better, but I am planning on upgrading to a weekend cruiser for short trips this summer.

 

[JB]

Re: 140 HP Seahorse won't start - start motor??

You have drifted off the topic, Madramire. Starting.

You need a fully charged battery. 11.3V with no load greatly sux.

Go to the Engine FAQs Forum and do the electrical troubleshooting in "Outboard won't start".

Once you can get her started, then worry about the compression. Compression measured with a weak battery is worthless.

 

[madramire]

Re: 140 HP Seahorse won't start - start motor??

Thanks JB, I am charging the battery right now, will give the Troubleshooting guide a check too.

Cheers.