FordSilly

maybe even try to disconnect The main charging cable and connector and try it.

muddyF-150

so I disconnected the alt at the battery and I still get the same results. I figured it would be the same as disconnecting it at the alt it self since both of the connectors are attached to the same cable going to the battery correct? like I said before not to sure about this since I am still in the newb stage of working on trucks and cars.

muddyF-150

im still going to take it down to oriley's and get it tested.. I didn't completely disconnect the alt I left the plug in connector still. doesn't hurt to get it tested since I do have life time warrenty for the alt since I just bought it last December.

muddyF-150

Update.. replaced the the alt with a brand new one. also replaced the starter with a brand new one. truck still turns over but still doesn't start, but will start with the belt off. the only thing that I have installed in my truck that isn't brand new is the A/C compressor.

muddyF-150

still starts up with the belt off and won't 9 times out of 10 with the belt on and when it does start with the belt on when it drops to idle it just dies. I have checked all my pulleys and they turn really easy. would my tensioner maybe be pushing to hard up on the belt to make it tighter and cause drag and make the truck not start?

muddyF-150

still need help. this thing has been sitting for 3 weeks now and I need to get it going.

twiggy2cents

Try disconnecting the ac compressor connector. The truck has a CASS(compressor anti slug strategy) system. Maybe you over oiled the system and it is hydro locking the compressor. When you disconnect the compressor it can no longer command it on and it will just turn the pulley. Also check that when not running you are able to turn the ac pulley without the center section turning

muddyF-150

I have tried to unplug the ac compressor also tried to turn the ac compressor when the truck is up and running with out the belt on and it turns freely. I only added one small can of 134 to the ac system just to get some oil in the new compressor. I have also discharged the 134 after this started to happen thinking that maybe it was causing the clutch to engage and cause drag on the crank pulley during start up and this also is a no go. I have already dumped about $600 into the truck trying to fix this problem doesn't seem like a lot but to me it is a lot of money and Im just really close to getting it towed to the local ford stealership and have them look at it cause I am pretty much out of ideas.

jamie930

did you pull a vacuum on the AC system after you replaced the compressor? Air in the AC system would cause a high discharge pressure, basically overloading the compressor and what is driving the compressor, the engine

twiggy2cents

That won't matter if he disconnects the compressor and it still does it.

Also the water pump and ps pulleys should spin with very little restriction. They should feel about identical to each other. When you crank it with the belt on does it slow down the cranking speed or does it sound the same?