My truck is a 5 spd 5.0 FI it starts like a champ when eng. is cold But when the eng. gets warm it drags like if the batt is dead. I have all ready replaced the alternator,plugs,wires,cap and button, and set the timing at 10deg even played with the timing added 2deg and removed 2deg, I can tell the difference in the lack of power and the added power but it still drags when I try to start it.

 

Sounds like either a bad cable or connection, or perhaps the starter needs to be replaced. I would check the cables and connections first.

 

Just put new starter and new cables on yesterday and I tried it out today and I still have the same problem.

 

Well, as it happens my "new, more reliable truck" crapped out all of a sudden yesterday. Started up, left home, stopped at hardware store, started up, drove to building site, stopped to move gate, tried to start, dead (or very nearly dead). Took off battery connections, cleaned at them for a bit (or so I thought), still dead, got it to roll-start (had a little bit of power to get the pumps and all working) once started all was fine and happy, good voltage, let it sit for a while, but dead again when turned off again. Roll-started (with more difficulty) after working for a while, got it home, dug out the battery charger. Didn't seem to be charging much, especially for acting so dead.

Found voltmeter, investigated. Lights and all worked fine with battery charger on; not with charger off. Checked some voltages - battery voltage fine. Began to suspect - found voltage between +battery post and +battery connector which I THOUGHT I had cleaned. Turn on headlights (no light), get a full 12V across that connection. Note that that connection is hot, while - is cool. Take connection off, connect charger to battery, battery starts taking a normal charge.

My task for this morning is to do a much better job of cleaning the terminals, grease the crap out of them, and reconnect all - hopefully that's all it is. Surprising how suddenly it struck - went from nothing wrong to not working in the course of 3 miles and 5 minutes, but everything else points to that being the problem - the other thing I had considered was that the battery might have shorted a cell all of a sudden, but it seems to be fine, and the measured voltage across the termal connection is clear indicator of a problem there.

Easy to see how that would grow - cruddy connection heats up a bit, heat makes it more cruddy, heats up more, gets even cruddier, finally fails.

Be careful about assuming that you've done a perfect job on the stuff you have done, but if you have, I'd suspect a failing starter solenoid.

 

Seems I was fighting a layer of corroded crap that yesterday's wire-brush skipped right over without denting, much less removing. Grabbed a hunk of 80-grit sandpaper, rolled it up, and ground away for quite some time before I finally broke through to (mostly) relatively clean lead. Debated about grease to use, decided on using copper-filled anti-sieze on the inside of the connection (plain grease should work - it will squeeze out from the metal-to metal contact, while preventng water and air fom getting in to corrode things). The anti-sieze will either be "better" since it's got copper in it and helps with conducting where the fit is poor (pits), or the copper in the middle of a lead to lead electrical joint will cause some sort of galvanic corrosion, making it a bad idea caused by too much thinking - time will tell.

For the outside of the clamps/posts, I coated all accessible surfaces with a wheel-bearing grease, as that was what I had handy for grease.