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Engine Turning over very Slowly (ITS NOT THE BATTERY)

R

rla0002

New member
I have a 1988 48 hp johnson tiller motor with push button starter. My issue is the engine turns over very slowly and will drain a fully charged battery quickly. The following items have been replaced. Battery (Several different batteries), battery wires (4ga), solenoid and starter. Issue still occurs. I have now determined that when removing the spark plugs (No Compression) motor turns over at required speed. When spark plugs back in, back to slow turn over.
Now with this being said, at random times, usually after 6-8 slow revolution starting attempts, the engine will turn over full speed, start up and will not have an issue until engine is cold again.

Any suggestions?
 
It could be your battery cables, I have seen them corroded inside the insulation to the point that it would not allow a vehicle to start.
 
Ron1 said:
Are you sure that the battery has high enough amperage. Because that sounds really weird.
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Ron, thanks for the help but I have used several different batteries. I have hooked the battery up to a running vehicle with jumper cables as well. I have had this engine for several years and the problem has worsened over the years.
I have come to the conclusion that it might be something internal within the engine block. The reason I have come to this conclusion is: I have bypasses the solenoid with a direct connection, battery to starter (both new and old one) and still have same slow revolution issue. When I manually spin the flywheel it seems to have an increased resistance to rotate in the same location during a revolution.

Any thought with this additional information?
 
Time to take the starter apart for an inspection. Maybe has worn-out brushes. Or maybe has shattered field magnets (it is a permanent magnet starter). Or could have a bad armature. I'm going to gamble on the magnets.
 
fdrgator said:
Time to take the starter apart for an inspection. Maybe has worn-out brushes. Or maybe has shattered field magnets (it is a permanent magnet starter). Or could have a bad armature. I'm going to gamble on the magnets.
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Starter was my original thought until I purchased a new one and have the same issue.
 
did you clean all the connections including where the starter bolts to the block use emery cloth it sounds like a bad ground
 
I will replace the battery tomorrow and clean the ground on the motor at the starter. Check all other connections as well.
In my past history with this motor, it requires a minimum of 660 CCA and normally works with a brand new battery. For some reason when I leave the engine connected to the battery for more that 3 day, it will drain the battery down and even after charging it, it some how "kills" the battery after a few uses. At this point, I usually have to return the battery to the store, they run a test confirming the battery is "dead" (not chargeable) and replace it. This is all in a period of roughly 1 year. I have done this cycle for 3 years now. I know this sounds crazy but it's the truth. My current battery is only 7 months old and came fresh off the charger. Basically, I am tired of dealing with this battery drainage issue and trying to find a solution. Also, I no other accessories running off the battery to possibly drain it.

Thank you all for your help.
 
if you are draining a battery as you say then that is the complete problem on all probability...two things are happening...you are sharing current with the drain problem when trying to turn the engine and therefore starving the starter of required power..if the battery has been in the boat and hooked then you are trying to start with a partially run down battery...

do you notice a spark when disconnecting or connecting the battery?if so this is wrong and you have a path to ground..if you take a multi meter on the rx1 scale fo you get a reading from the disconnected positive battery lead to ground?.....

if you are draining the battery with nothing but the two motor leads connected the you have a leakage to ground...get the problem on a meter where you can see it and start disconnecting things til it goes away..i would start by disconnecting the output of the charging system....then unplug the big plug going to the controls if you have it..

keep in mind you may have a wiring error if anyone has been replacing parts etc...
 
The battery drainage problem should be an easy fix for somebody that understands the electrical system. Sounds like you have already spent way more $$$ on it than you would have if you had gotten some assistance. Yeah, I know, I am a die-hard, card-carrying Do-It-Yourselfer too. But sometimes somebody else can do it better.
 
fdrgator said:
The battery drainage problem should be an easy fix for somebody that understands the electrical system. Sounds like you have already spent way more $$$ on it than you would have if you had gotten some assistance. Yeah, I know, I am a die-hard, card-carrying Do-It-Yourselfer too. But sometimes somebody else can do it better.
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You are exactly right. It doesn't matter what the project is, I have always wanted to solve the issue myself. I always tend to spend more money doing it this way but in my mind, I gained useful (or sometimes useless) knowledge. Plus its always fun to have a project to tinker with in the shop.
 
papyson said:
if you are draining a battery as you say then that is the complete problem on all probability...two things are happening...you are sharing current with the drain problem when trying to turn the engine and therefore starving the starter of required power..if the battery has been in the boat and hooked then you are trying to start with a partially run down battery...

do you notice a spark when disconnecting or connecting the battery?if so this is wrong and you have a path to ground..if you take a multi meter on the rx1 scale fo you get a reading from the disconnected positive battery lead to ground?.....

if you are draining the battery with nothing but the two motor leads connected the you have a leakage to ground...get the problem on a meter where you can see it and start disconnecting things til it goes away..i would start by disconnecting the output of the charging system....then unplug the big plug going to the controls if you have it..

keep in mind you may have a wiring error if anyone has been replacing parts etc...
Click to expand...

You are right on track. Thank you for the help.
And yes, when I purchased the motor a few years ago, the man said he had rewired the motor converting it from controller box to tiller. Possibly the leakage is within the wiring.?

Thanks you for you help
 
Hi all im having the same issue with my 1980 Johnson 85 v4 the starter engages but turn over really slow like it can't be bothered
But will start after a few times would this be electrical ?? because whet its running its fine and ,smooth any help would be great
I started a new thread on this
Thanks for any advice ....mark
 
Mark: OK, good. You started a new thread. Changing the subject here would only confuse things.
EDIT Where is the new thread?
 
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Hi papyson I've only had the boat finished this week and this starting issue seems to be new and most of the wiring to the engine is new the flywheel turns over slow but it will fire ?? Brand new battery holding charge but I have noticed when I do turn the engine over the volt gauge drops to zero on the key but the returns to show battery state once released I have an electrical choke so there is n idle lever so I start the engine with the throttle lever disengaged from gearbox any help would be great as this I my first time owning my own boat .....mark
 
kimcrwbr1 said:
When you pull the spark plugs will the flywheel turn easy by hand?
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Yes, when I pull the spark plugs the flywheel is easy to spin. The starter also has no problem turning the engine over at the required rev/min. It is only when the spark plugs are in that it will. It turn over fast enough.

Yesterday I checked all the wiring also checked that the solenoid was getting 12v. When not under stress, the starter reads 12v but when put under a load it drops to 6. Is this normal? I also checked the rectifier and stater both good and no battery leakage.

I took my battery to battery source and had it tested. They said it was fully charged but did not do a CCA test. I am thinking that now the battery's CCA have diminished? In the past I have only had good luck starting the motor when purchasing a brand new battery.
 
I would start with an inspection of the starter.-----Take it apart, inspect brushes.---Take an ohm reading ( digital meter ) from shaft to the commutator.---Easy to do and costs no money to do !
 
a fully charged battery should read 12.7 volts..when engaging the starter the voltage on the post on the starter should exceed 10 volts...you are saying 6 at one point and saying zero in another entry....do as racer suggested....thats a must to do and do it first..after that(if it shows no problem) the next step depends on your depth of understanding dc voltage and troubleshooting.. taking a random voltage reading without understanding what the reading is telling you is little more than shotgunning the problem.. i am not being critical of you...but it appears that you may have multiple problems...you have always had a problem since purchase so that tells me that you probably bought another persons problems...so you may have a wiring error going back to when someone changed the controls....then on top of that the motor has been operated with the problem for 4 years and that drawing of random and excess current may have caused more problems..you do not have standard wiring..it has been altered...its impossible for us to remotely eyeball what you have and make any sense out of it....it may be time for you to buy a couple hours time of a good tech..

just my opinion and good luck
 
papyson said:
a fully charged battery should read 12.7 volts..when engaging the starter the voltage on the post on the starter should exceed 10 volts...you are saying 6 at one point and saying zero in another entry....do as racer suggested....thats a must to do and do it first..after that(if it shows no problem) the next step depends on your depth of understanding dc voltage and troubleshooting.. taking a random voltage reading without understanding what the reading is telling you is little more than shotgunning the problem.. i am not being critical of you...but it appears that you may have multiple problems...you have always had a problem since purchase so that tells me that you probably bought another persons problems...so you may have a wiring error going back to when someone changed the controls....then on top of that the motor has been operated with the problem for 4 years and that drawing of random and excess current may have caused more problems..you do not have standard wiring..it has been altered...its impossible for us to remotely eyeball what you have and make any sense out of it....it may be time for you to buy a couple hours time of a good tech..

just my opinion and good luck
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I think you confused part of my post with part of mark069 whom chimed into this thread with similar issues. But thank you for you help. Problem has been solved. The wiring conversion from controller to tiller from the original owner was an absolute mess. I ended up cutting out everything and rewiring according to the shop manual wiring diagram. Problem Solved!! What a great feeling.

Thanks again for your help as well as everyone else's.
 
I have the same issue, except with my 1988 Johnson 88hp outboard, it doesn't crank up and the motor continues to rotate slowly even after I remove the key from the ignition until the battery goes dead.
 
I think you had carbon built up on the pistons and rings. And stuck rings as it is variable with temperature. 2 strokes are known for carbon fouling. Also coked oil deposits on any art subject to heat. It forms st higher heat and tom and when it is cold the parts are no longer expanded and it jams up the engine.
 
racerone said:
Likely need a new starter.------And check out all t5he wiring or you will ruin the new starter again.
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I'm going to disassemble the starter today and see what the inside looks like. I'm hoping it's the wiring because I've had problems in the past with field magnets coming loose from the motor housing. .thank you for the reply and I will post updates as I check different things, starting with the starter.
 
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