# MTD No start



## davbell22602 (Jun 12, 2011)

MTD 18 Lhead twin Briggs, 42in cut and hydro transmission. Model 690.

New battery(April 2012 from Lowes), new blade safety switch, new positive battery cable, new fuse, new key switch and rebuilt starter with new brush retainer and pinion gear assy.

Will not start with key. At first I could jump the solonoid or starter to get it spin over. Now I have nothing but a jolt when jumping the ground terminal on starter. I get the test light to light up when checking the new battery. When I test light clipped to the neg post it lights up when touching big ground post on solonoid, B & S on key switch. When having it clipped on the pos terminal on battery it will light up when checking stud on starter, pos big post on solonoid, and when I check the little ground terminal on solonoid it trys to spin the engine over then starts giving off really fate sparks. Seat switch temp. bypassed with a piece of cardboard wedged in between the metal contacts.


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## jhngardner367 (Apr 5, 2011)

The terminals you mention,are battery + terminals,not ground terminals. The + battery cable should run to one of the large solenoid terminals.From the other large solenoid terminal,it runs to the starter +( feed)terminal.The starter is grounded through its mounting bolts.
When you touch the small solenoid spade terminal,with 12v +,it should make the engine turn.
Try to find the fuse,in the harness,and see if it's good. Also,check the ignition switch connector,to see if it's rusty. Then check the wire that is marked "s",on the switch to see if the test light comes on,when the key is turned to the "Start" position.


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## davbell22602 (Jun 12, 2011)

jhngardner367 said:


> The terminals you mention,are battery + terminals,not ground terminals. The + battery cable should run to one of the large solenoid terminals.From the other large solenoid terminal,it runs to the starter +( feed)terminal.The starter is grounded through its mounting bolts.
> When you touch the small solenoid spade terminal,with 12v +,it should make the engine turn.
> Try to find the fuse,in the harness,and see if it's good. Also,check the ignition switch connector,to see if it's rusty. Then check the wire that is marked "s",on the switch to see if the test light comes on,when the key is turned to the "Start" position.


The fuse is good. The engine wont spin when touching the spade terminal on the solonoid. All it does is send a jolt/click sound to the starter and tries to spin it. Test light comes on when key in start postion on the "S" wire.


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## TecumsehBriggs (Jun 17, 2011)

Remove the starter & bench test it. Could be high resistance in the starter motor itself, or bad brushes. In that case, replace the brushes or starter.


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## davbell22602 (Jun 12, 2011)

TecumsehBriggs said:


> Remove the starter & bench test it. Could be high resistance in the starter motor itself, or bad brushes. In that case, replace the brushes or starter.


Built starter with new brushes and pinion gear. Starter spins just fine bench testing it. Tried the new battery on different mower that had 18.5 intek briggs and spins with no problems. Replaced solonoid also.


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## davbell22602 (Jun 12, 2011)

TecumsehBriggs said:


> Remove the starter & bench test it. Could be high resistance in the starter motor itself, or bad brushes. In that case, replace the brushes or starter.


Built starter with new brushes and pinion gear. Starter spins just fine bench testing it. Tried the new battery on different mower that had 18.5 intek briggs and spins with no problems. Replaced solonoid also.


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## jhngardner367 (Apr 5, 2011)

Remove the sparkplugs,and try to roll it over with the starter.
It should spin freely,and quickly.If not,it's either the starter,or the battery.Even though the battery is new,it could have 12v,but little, or no, amperage.
I've recommended my customers to get the highest CCA battery they can,as the normal garden-tractor batteries don't have the amps needed,for used machines.


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## davbell22602 (Jun 12, 2011)

jhngardner367 said:


> Remove the sparkplugs,and try to roll it over with the starter.
> It should spin freely,and quickly.If not,it's either the starter,or the battery.Even though the battery is new,it could have 12v,but little, or no, amperage.
> I've recommended my customers to get the highest CCA battery they can,as the normal garden-tractor batteries don't have the amps needed,for used machines.


I'll give it a try but I think this more of a electrical issue than starter or battery. Gonna replace the starter and negative cable. The starter has new brushes in it.


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## dangeroustoys56 (Jul 26, 2010)

I have a number of twin cylender motors- i have to say it does take quite a bit of juice to rotate all that around . I actually have a 90's GT6000 that states on the battery cable to use no less then a 600 CCA battery.


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## davbell22602 (Jun 12, 2011)

The CCA battery thats sold around here is 300 CCA. The battery would actually spin the engine over when I got the battery home then when after few days trying to start it with the key then I started coming with nothing at all even with jumping the solonoid or starter and still like that today except it spins over one full turn then pauses stops. Then I have to retouch solonoid posts with screwdriver so it will spin one full turn then stop again.


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## davbell22602 (Jun 12, 2011)

jhngardner367 said:


> Remove the sparkplugs,and try to roll it over with the starter.
> It should spin freely,and quickly.If not,it's either the starter,or the battery.Even though the battery is new,it could have 12v,but little, or no, amperage.
> I've recommended my customers to get the highest CCA battery they can,as the normal garden-tractor batteries don't have the amps needed,for used machines.


Spins freely really fast. when jumping the 2 posts on the solonoid. Still nothing when trying to use the key switch.


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## Bill Kapaun (May 8, 2007)

"...When having it clipped on the *pos terminal on batter*y it will light up when checking stud on starter, *pos big post on solonoid*,..."

There should be no current flow through the test light, since it's just the 2 ends of the POS battery cable.

There has to be a poor connection somewhere between the battery POST and the Solenoid BIG STUD.


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## davbell22602 (Jun 12, 2011)

Bill Kapaun said:


> "...When having it clipped on the *pos terminal on batter*y it will light up when checking stud on starter, *pos big post on solonoid*,..."
> 
> There should be no current flow through the test light, since it's just the 2 ends of the POS battery cable.
> 
> There has to be a poor connection somewhere between the battery POST and the Solenoid BIG STUD.


Everything is tight and has good connections. All new battery cables and starter cable. So what do I replace the starter or wiring harness?

What about the hydrostatic safety switch? Does this mower have one?


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## Bill Kapaun (May 8, 2007)

I think we need to back track a bit- since there are 2 BIG studs on the solenoid.

With the test light connected to battery+ post.
You are simply trying to run the starter through the test light, IF you are connecting to the starter motor stud. It will light, since thee SHOULD be current flow.

Touching the B terminal on the key switch. The B terminal should be wired directly to the battery +. 
Battery + cable goes to solenoid stud. SMALLER red wire goes from there to B(attey) terminal of the key switch, through the fuse. (B terminal is the 12V supply to the system)
You should NOT get a light under any conditions, unless the small red wire or fuse is bad.
Did you get the CORRECT key switch. Even though they may look identical externally, they can be VERY different internally.

I think a better plan is to get the battery charged. It may be new, but unlikely that it was fully charged and I have a hunch you have simply ran it down too far.

Is this a BRIGGS OHV engine?
IF so, it may need a valve adjustment to allow the compression release to work.


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## davbell22602 (Jun 12, 2011)

Bill Kapaun said:


> I think we need to back track a bit- since there are 2 BIG studs on the solenoid.
> 
> With the test light connected to battery+ post.
> You are simply trying to run the starter through the test light, IF you are connecting to the starter motor stud. It will light, since thee SHOULD be current flow.
> ...


Battery has been charged and this is old school Lhead twin 18hp Briggs. Yes its the correct key switch from Stens 430-538 thats same as MTD 925-0267A.

My jump box wont even work cause I get nothing when turning the key. I guess I can continue throwing money at and try mtd key switch or oregon.


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## Bill Kapaun (May 8, 2007)

I missed the old flathead in your first sentence! DUH!

It's possible you DO have a "tired" starter.

I'd check the ground sides of the crank circuit before I replaced it though.
That includes things such as engine mounting & starter to engine bolts, since those are all part of the ground circuit. They're out of sight, and thus tend not to get thought of.


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## jhngardner367 (Apr 5, 2011)

Was the starter dropped,at any time? I have one here that the owner dropped,when removing it. Found a hairline crack in one of the magnets,and it won't work right,either.


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## davbell22602 (Jun 12, 2011)

jhngardner367 said:


> Was the starter dropped,at any time? I have one here that the owner dropped,when removing it. Found a hairline crack in one of the magnets,and it won't work right,either.


The starter wasnt dropped. I have new brush retainer on the starter. The new batttery has 230 cca. I know it spins when bench testing the starter on the 230cca battery.


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## dangeroustoys56 (Jul 26, 2010)

Well, reason it spins easily is theres no load on it - that lil battery is trying to spin 4 valves, a crank and two pistons over - thats a pretty heavy load for that lil battery.

I dont use tractor batteries, i use either vehicle or farm tractor sized batteries - if the area for the battery isnt big enough , you might have to opt for a motorcycle/atv battery.

Another thing to check is when buying a battery, make sure its a newer battery ( they should have a date code sticker - usually the letter is a month- A= january , ect and the number is the last number of the year - they should be taken off the shelf after a year in the store) if possible also check and make sure theyre holding at least 12 volts at the store - sometimes they can get a dead cell.

I bot my last battery at TSC back in 2008 a 650CCA and i think its finally dying ( takes forever to charge it) - i think its an 'interstate' brand.


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## davbell22602 (Jun 12, 2011)

dangeroustoys56 said:


> Well, reason it spins easily is theres no load on it - that lil battery is trying to spin 4 valves, a crank and two pistons over - thats a pretty heavy load for that lil battery.
> 
> I dont use tractor batteries, i use either vehicle or farm tractor sized batteries - if the area for the battery isnt big enough , you might have to opt for a motorcycle/atv battery.
> 
> ...


But I still cant turn the engine over the key. So all that is battery related then?


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## davbell22602 (Jun 12, 2011)

Took your advice and got a different battery with 340 CCA, 425 CA. The engine spins just fine when jumping the two large posts on the solonoid with the spark plugs back in the engine but still nothing when trying the key switch. Bad wiring harness?


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## Bill Kapaun (May 8, 2007)

Jump 12V directly to the SMALL Stud on the starter solenoid.
IF the solenoid, starter motor & battery is good, engine should crank.

IF it cranks that way, but not from the key switch, the problem is the key switch, associated wiring or the FUSE. 
You have checked the FUSE haven't you? 
It has to be good to get 12V TO the key switch TO the solenoid.......


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## jhngardner367 (Apr 5, 2011)

I have to agree with billkapaun.It sounds like the switch.or fuse.


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## davbell22602 (Jun 12, 2011)

Bill Kapaun said:


> Jump 12V directly to the SMALL Stud on the starter solenoid.
> IF the solenoid, starter motor & battery is good, engine should crank.
> 
> IF it cranks that way, but not from the key switch, the problem is the key switch, associated wiring or the FUSE.
> ...


Good fuse, new key switch, new clutch satety switch, new blade safety switch. I'll have another key switch here on monday to try.


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