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Discussion Starter #1
Took my XL out for the essential shopping today, via the petrol station. Came to start after filling up and the starter was hardly turning it at all.
Did this to me before, and I was concerned about killing the battery with repeated start attempts so left it until I could get another car on standby in case I needed to jump start. didn't have that car available until the next day, so by the time I come to try it again it was cold and started fine. Now today was a hot start after a little drive to loosen things up.
I remembered the previous problem and just sat there waiting for it to cool, half an hour later it started fine.
Previous to this car I had a V8 Landrover which would do the same. Starter would go weak when it was hot. Replaced the starter with a Wosp one and it was all fine. (sold that car now, shame.)
My question is; Is this a known thing on these V8s too, with the starter being right next to the exhaust. On the landy I tried a heat shield, before replacing the starter, which partially worked. Is that something people do on these V8s?
She didn't have a problem last year at all, but I have recently replaced and upgraded cooling parts (to solve a cooling problem and I bust a radiator) now she has a Derale performance flex fan fitted. I'm wondering is that doing such a great job at cooling the radiator that it's redirecting all the heat past the starter and making that too hot?
 

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not likely the fan has anything to do with it. you need to get a voltmeter attached to the battery post at the starter. check it while cranking. bet you will see alot less than battery voltage indicating bad (high resistance) cable from relay to starter
 

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What your XL is experiencing is called "heat soak".

When you shut it off after being fully warmed up, the temperature of the block (including the starter) actually rises.
Starters don't like excess heat.
They crank slow and draw excess current from the battery.
Extreme cases will not crank at all, the solenoid just clicks.

Make sure your battery is good. have it load tested.
Batteries don't like heat either.

As extech said, check voltage at the battery when cranking hot.
The high resistance could be cables, solenoid, or even a poor ground at the starter.

Consider that if you take a piece of wire and pass current thru it and measure said current...
Then heat the wire and again pass current and measure... the heated wire will have trouble passing the same amount of current.
Heat in electrical components and wires causes increased resistance to electrical flow.

Now consider that your starter has many winding's with many wraps of wire (the armature) and when it get s hot.... well... you know...

As a test... next time you have it fully warmed up (I'd do this after a long trip and returned home on my own driveway),
shut it off and lift the hood to let the heat out.
Wait a bit (10 minutes seems about right) and then try to start.
If it cranks easier then you know you have a heat soak problem.

A better (new) starter, battery, and big thick battery and starter cables, and good solid cable connections and grounds, will all help.
 

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Discussion Starter #5
Thanks guys, sounds like what I was thinking. might try getting some form of heat shield on the starter, seemed to work on my Landy.
 

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Could this be initial ignition timing? If noting else changed from when it was starting well when hot, then I'd test the battery and cables first, but if the initial timing got bumped out of place, that might be something to check if all else fails.
 

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Check your old corroded wiring. Check battery posts. It is an electrical problem, when wires are bad and they can look good ,but still be bad on the inside. They cause resistance in the flow of electrons. That causes heat and makes the starter turn slow and beat down your battery. here is what I would do.
1. Clean battery posts and battery cable connectors with wire battery brush ( $4 at parts store)
2. disconnect and clean both cables from battery to solenoid, and solenoid to starter (free)
3. Disconnect battery cable at solenoid and do a voltage drop test. (Free)
4. Disconnect solenoid cable at starter and do voltage drop test. (Free)
5. Make sure all connections are tight and making good contact. A loose battery cable will cause those problems too.

total $4 and you should be good, unless someone has changed those cables with skinny cheap ones. Buy good thick quality ones if you must replace them.
 

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a voltage drop test is done with the circuit complete. current must be flowing at the time of the test. neg lead on the most neg. point of what is tested. ei pos lead at battery post, neg lead at battery side of relay. this tests how much voltage is consumed in that cable. no reading will be displayed untill current flows(cranking the engine). readings above .2v indicate excessive resistance
 

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i have a 67 with blown 545 fpa headers it gets hot. but I am running a 3hp mini high torque starter ,all my cables a 00, and my bat ground is right to the starter, and a separate engine ground and a separate body ground, all ignition system wiring is 10g pos and neg, my motor spins great look at your grounds remove them clean the surface use copper ends
 

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Those green knob battery disconnects will do that after a while.
 

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Discussion Starter #12
I have now got the heat shield around the starter, so we'll see how it goes. so far so good.
 
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