Since the summer of 25 I have been having what I thought were battery issues. At times I could leave home and run errands and then somewhere on the way home the 109 would fail to start. Often enough that I bought a Avapow 6000 jump pack. I would hook up the jump pack, turn the key and POW it started! Even after no clicks with the key.
I suspected the battery because the instant start with the jump pack and the fact that it was 13.5 years old. It was a Sears Platinum marine dual purpose deep cycle AGM with 1150CCA, a 31M battery. My guess is it had worn out it's welcome. Since I was spending money on my roof and paint and rain gutters I put off the battery issue since I wasn't driving often.
So it wouldn't start, I'd charge the battery with my NOCO genius 5 charger and it would start. I did this a few times in Dec and into Jan. Always with the same result. It would start at home and my dash voltmeter showed 13v+ while running/driving. Then I would hit the hardware store or Foster's and no go.
Of course over all this time I checked for loose connections on the battery terminals, fuse box, starter solenoid. They all seemed good. Very confusing and frustrating.
Two weeks ago I bought an Ancel car battery tester to check the battery internals.
https://www.amazon.com/dp/B01M0ARG3X?ref=ppx_yo2ov_dt_b_fed_asin_title
I got good readings on my battery when fully charged, but it would be 14.4v and I would take it off the charger and it would drop down to 12.88 over the hours. Heck I kept it charging all night and it was 14.4v in the morning and it dropped to 13.23v with the charger on during the day! The Ancel still said good battery..... I ordered a new starter solenoid off Ebay just incase;
https://www.ebay.com/itm/271570739389?mkevt=1&mkpid=0&emsid=e11401.m144671.l197929&mkcid=7&ch=osgood&euid=7d576e77b02b4023ab52eff7f863259e&bu=43519496236&exe=0&ext=0&osub=-1%7E1&crd=20260117071536&segname=11401
I asked one of my neighbors over he used to work on aircraft in the USN, so I figured he knew more than I(not too difficult!) I hooked up the Ancel and pressed the test button and it said REPLACE BATTERY My first indicator the battery was bad.
Three days later I went to Batteries Plus and bought a new AGM dual purpose deep cycle battery only this time Money held me back and I bought a group 27 with 900CCA and not the bigger 31. It was $550..... Swapped it right in the parking lot, turned the key...click.......tried again and it fired right up! WHEW! had me worried!
Then I went grocery shopping and it wouldn't start. WTF!!!!!!! I jumped it and came straight home ignoring my other errands.
Put away groceries and scrutinized my wiring diagrams. One thing kept popping into my mind, WTF! WTF? The next day I frelling checked everything I could with multimeter, test lamp, wriggling, pulling on switches, terminals, connectors, pulling what little hair I have out. You don't want to see that picture....... Finding nothing I decided to pull the starter.
I began that yesterday and nothing came out willingly! You know the drill? Remove bonnet tire, Throw back bonnet, disconnect battery and all hot leads to it. Remove and clean ground strap from engine to chassis, just in case, reinstall. Undo wires at starter solenoid. Remove 17mm nut from bottom, 17mm bolts from top of starter. Try to wiggle starter out. Realize the ground strap is in the way. Remove ground strap. Wiggle starter more. Realize the exhaust down pipe is in the way. Undo clamp at bottom of down pipe. Try to wiggle the fuck out of it and it doesn't move. Remove the clamp to the rear with the donut inside. Ya need that donut out to get enough room to wiggle the gd exhaust. Get a frelling huge prybar to wiggle things, 15 minutes later the donut is out. Pry the crap out of the downpipe and nothing moves, but ya keep on trying. Finally after some god awful energy expense things start moving and with one last tug-a-wiggle the downpipe drops to the ground.
Then you know the starter can come out because you remember changing it in 2019, 7 years ago! Lots of turning upside down, backwards and more wiggling than a Republican, by moving it further to the front of the 109 it almost falls out.
I took it over to the battery and put jumper cables on it to test it.
click..........click..........spin..........spin...........
I then had a good look at the solenoid.
There are signs of arcing on the nut holding the wire from the solenoid to the starter. I took it to my workbench and pulled that apart. The nut was kinda tight to rotate but it was not tight on the wire connector. The following pics show the nut and connector
I began to clean things up as I realized I had found my loose connection and had probably bought an unneeded battery. I filed the connector flat and wire brushed everything. It was then that I realized that wasn't just some funny UK nut, but the lock washer and flat washer were welded to the nut!
Well my new solenoid came in the day before, so I started to compare hardware and replace like for like today and get it all "factory". I even pulled out my spare starter which I rebuilt after replacing it with this one. I don't have enough of the thin nuts, which are 8 x 1.25 by the way. All was clean and flat. I seriously tightened the bottom nuts this time. After all was together, a test with the jumper cables was SPIN BABY SPIN!
I didn't have time today to put it all back together, due to time constraints. So tomorrow.
I did take a picture of the old solenoid numbers just in case the one I got is wrong
So when I sat down to write this I searched my blog for starter. I wanted to see why I replaced the first one and when. As already mentioned it was Feb 2019. The reason was the exact same issue! Now how dumb am I for not remembering that?! Don't answer that! Not only that but when the 19j engine was in It had the same issues but it turned out to be the lower stud was loose on the solenoid. Methinks the starter is too close to the down pipe and excessive/prolonged heat is causing the nut/stud to expand and contract at different rates. What do you think?
https://poppageno.blogspot.com/2019/08/200tdi-starter-replacement-in-series.html
25 Jan 2026
Yesterday, I put it all back together with much confidence. Got the starter in and hooked up the exhaust pipe and battery cables. The exhaust I held up with a bottle jack whilst I tightened the fasteners.
So far so good, no fires! I tried the key and Click........click, ...click....What the frell? I was bummed. Thought about it a few min and decided to pull the starter out again and either put in my spare or replace the solenoid. Now I was missing the old day when the solenoid was mounted next to the air cleaner!
I got it out and kept thinking how I could check it off the vehicle, I still wasn't sure it was not my tractor switch going bad. I figured out I needed to hook up jumper cables just like when installed, ground to the case and power to the upper stud. Then I used a jumper with alligator clips from the + on the battery and I tickled the trigger bayonet fitting and Click......click........click, every time.
I then got my spare out and tried the same thing and Brrrrrrrrrrr, it sprang to life. So it HAD to be the solenoid.
That' when I had a bite for lunch and after started swapping the new solenoid for the old. Gotta admit the rubber seal goodie is shit, already has cracks in it and the old one didn't fit. I cleaned up all the crud and evidence of arcing as I went along.
Then since I was on a roll and had all the tools out I put the starter back in, hooked up all the wires BEFORE doing the exhaust and tested it. Again NO Fires! Lucas didn't let the smoke out. Plus the starter turned the engine and it fired right up! Quickly I shut it down as the exhaust was all in the engine bay and my face.
The exhaust was reinstalled, amazing how quick when you know the steps. Then I started it again and after shutting it down, put away the tools! I took a shower and had a celebratory beer! My second one this year! Did I say I was on a roll? I don't drink much.
So today I did an autopsy on the solenoid. My conclusion is there was no obvious failure such as broken wire or crud. Every part that could move did, all the wires were good, on the multimeter all showed continuity. The is as you can see in the pics some evidence of arcing, which I would expect as the magnetic field moves the solenoid to engage. So I dunno. Just lived the good life up to the end!
Best I can figure is that the magnetic field couldn't move the contact far enough to engage power to the lower stud. You can see there is some melting and shrapnel from arcing. Onr thing which might hace helped with this was the upper inlet power bolt/stud was a tiny bit loose and if it sticks out enough the moving contact will not touch the lower bolt/stud. In retrospect I think maybe the battery was partly at fault also, if it wasn't putting out enough to make the coil fully move the solenoid contacts.........click.
On with the show!
Note to self; buy another solenoid...............