strange non starter

[the_big_fact_hunt]

i have a problem with my other van, a 2002 LDV crewbus, its fitted with a 100ps Di turbo and has 60k on the clock

my van will not start, however much i try, the only way is towing it and it only needs about 3 feet to bump it. i really need some help here as i'm scratching my head.

PROBLEM
The battery wont turn it over more than about 3 slowish rotations before it dies, it feels like a flat battery but it isnt, it used to spin over faster. It now has a lorry battery that is good, i know because it has just been used on an 11 litre coach, its been charged and tried with the booster on but it still wont spin over fast or more than a couple of rotations. I have also tried the battery from my tourneo which is also good but its still the same.

HISTORY
About 6/7 weeks ago the starter failed (just kept spinning and not engaging) so i swapped it for a big old type transit one (same number of teeth) and it started straight away. It was fine for the couple of days i used it, then about 7-10 days later it felt like the battery was flat, but it started with a jump from my other van, it was ok then for the rest of the day but failed again the next day so i assumed the battery was shot. I got a lorry battery and have only just gotten round to fitting today it as it needed a frame to lift it up over the PAS box due to its size.
It jump started ok midweek when i had to move it, but yesterday it would not start unless it was bumped/towed and then it only takes about 3ft to fire it up.
We have checked everything we can see, earths, leads etc, but it wont turn over much, even with an industrial garage type charger on it.

I am going to swap the starter for a known good small one from my other van when i can to rule the starter out in case its seized or too tight to spin, as its the only other thing i can think to try.

Has anyone experienced this before, or have any info or suggestions for me???? i am really stuck now.

[ake]

Sounds to me like a bad earth connection Did you clean them all up when you fitted new starter

[the_big_fact_hunt]

didnt clean the earth to the starter, but it was all clean anyway ( the van is ex RAF and extremely clean) and it started fine after fitting the starter, just seems whatever we connect it to it wont start, unless we bump it

just noticed my 1000th post was about start of this thread about my other van

[ake]

It could be that there is a slack or dirty connection and it has burnt itself to the point of not working, I would check and clean them all again

[the_big_fact_hunt]

will look at it when i can in daylight, we did make a new earth lead to the battery as the old one wouldnt reach, its clean and good, and the problem was there before anyway, but i will check the other leads

this is the kind of battery on it now

[the_big_fact_hunt]

took the starter off today, tried it before removal, still the same, turn then die. Once the starter was off i treid it direct with jump leads and just got sparks, no spinning or anything, beginning to wonder if its got a bad connection inside

[spospe]

It sounds like it could be brushes and / or the commutator. I had a faulty starter once and it was caused by a broken spring on one of the brushes not pressing it tightly enough onto the commutator.

[the_big_fact_hunt]

finally got a replacement starter fitted tonight, van started straight away, annoying as the starter fitted a few months ago was a recon off my mates shelf and worked when first fitted and then displayed symptoms of battery failure (slow turning then dying). Never known one to do that before