1997 5.7L thunderbolt ignition. Slow crank

findinghomer

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Change cables and two starters doing the same thing would tell me it's not an electrical problem.

Have you checked the level of your oil, is it correct?

Remove the plugs and see if it cranks the same
Yes I have checked the oil before I even took it out. I didn't change it this year because I just changed it last year and only had it out about three times and it looked good still. So I just checked the level, It was fine. Also the plugs are already out of it.

I have even bypassed the dual switch and hooked both batteries up independently straight to the starter. Eliminating the cables from the switch. I've hooked a jump pack up to it no change, I've hooked a car with jumper cables up to it at one point it seemed like it was a little better but still slower than it should be. No matter what I do slow crank
 

nola mike

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Yes I have checked the oil before I even took it out. I didn't change it this year because I just changed it last year and only had it out about three times and it looked good still. So I just checked the level, It was fine. Also the plugs are already out of it.

I have even bypassed the dual switch and hooked both batteries up independently straight to the starter. Eliminating the cables from the switch. I've hooked a jump pack up to it no change, I've hooked a car with jumper cables up to it at one point it seemed like it was a little better but still slower than it should be. No matter what I do slow crank
does it spin easily by hand?
 

findinghomer

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does it spin easily by hand?
I don't really know how to do that.. do you mean by turning the bottom pulley with a socket?

There is a 16 mm bolt on that pulley that I can't turn with a 3/8 ratchet. Should it turn easily with that? It feels like the bolt is tightening , I don't want to turn it too much and snap the bolt off lol
 
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nola mike

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I don't really know how to do that.. do you mean by turning the bottom pulley with a socket?

There is a 16 mm bolt on that pulley that I can't turn with a 3/8 ratchet. Should it turn easily with that? It feels like the bolt is tightening , I don't want to turn it too much and snap the bolt off lol
Yes, good call, don't turn it like that. That bolt can snap. That said without plugs it shouldn't take much force (assuming you're in neutral). A few different ways to turn it, either by turning one of the accessory (alt, ps) pulleys, using a special tool, put a couple of bolts in the balancer and turn with a screwdriver wedged between, etc. If it doesn't turn easily at this point I'd pull the valve covers and make sure all of your valves are opening and pull the drive to take that out of the equation (although that seems unlikely if it's otherwise running well).
 

findinghomer

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Yes, good call, don't turn it like that. That bolt can snap. That said without plugs it shouldn't take much force (assuming you're in neutral). A few different ways to turn it, either by turning one of the accessory (alt, ps) pulleys, using a special tool, put a couple of bolts in the balancer and turn with a screwdriver wedged between, etc. If it doesn't turn easily at this point I'd pull the valve covers and make sure all of your valves are opening and pull the drive to take that out of the equation (although that seems unlikely if it's otherwise running well).
I did run voltage test. Here's what I found this is with each independent battery hooked directly to the starter no battery switch.

Batt 1: 12.4 volts at starter and battery when off, 9.5- 11 v At the battery when cranking, and 9.1 -9.5v at the starter.

Batt 2: 12.2 volts at starter and battery when off, 10v at battery when cranking, as low as 8.8v at the starter when cranking.

Both of these batteries will start my truck just fine, but is this a bad way to determine the battery having enough cranking power for the boat? My truck has a V8 in it, engine turns really strong with these batteries. And there both pass a load test at O'Reilly's. Or do you think it might be possible it's the batteries?
 

alldodge

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Sorry about my previous questions, you mention about pulling plugs

Batt 1: 12.4 volts at starter and battery when off, 9.5- 11 v At the battery when cranking, and 9.1 -9.5v at the starter.

Batt 2: 12.2 volts at starter and battery when off, 10v at battery when cranking, as low as 8.8v at the starter when cranking.
Could be your meter is off a tad (fully charge should be 12.7V), and you did have them tested.

Have you pulled the drive yet?
Could remove the belt going to the raw water pump so not to damage impeller, or connect hose to bell housing
 

findinghomer

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Sorry about my previous questions, you mention about pulling plugs


Could be your meter is off a tad (fully charge should be 12.7V), and you did have them tested.

Have you pulled the drive yet?
Could remove the belt going to the raw water pump so not to damage impeller, or connect hose to bell housing
I have not removed the drive yet. I'm going to get a new battery and see if anything changes. I did change out the positive battery cable to the starter no change. So now I have a brand new ground cable, a brand new power cable, And I have the battery connected directly to the starter I took the dual switch out . Both batteries tested and got a passing grade. And they both start my truck lol. I wonder if the starter I got is a dud but it's slow crank on both starters...
 

findinghomer

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I have not changed my plugs in a long time but since I have them pulled I figured I would share their condition. Do they look rusted to you? The body on all of them that sits outside of the engine all have rust on them, but it doesn't look like they are rusted that goes into the motor. What do you think?
 

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findinghomer

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Plugs look fine, maybe a tad rich but nothing to worry about
Yeah and I know I'm running a little rich because I can't quite get it adjusted properly, but that's kind of what led me to all this. Hard start went hot. So when I got back for my 4th of July trip I started it on the muffs in the driveway and it fired up fine, I ran it to temperature and then shut it down. Because I wanted to come back out In 15 or 20 minutes and start it when it was warm. Of course it had a hard start , but at least it was cranking fine then it eventually started showing symptoms I'm behaving now, dead battery. But the battery isn't dead. I just went and hooked up my 2022 Highlander up to the boat through jumper cables. Doesn't help. I would think that's a sign of it definitely not being a battery, do you think it's a waste of time for me to go ahead and buy a new battery or do you think I should try it? This battery fires up my truck and it passed a load test at O'Reilly's and it's showing that it's fully charged. But I'm thinking maybe I should just buy a new battery before pulling the outdrive because I always have a hard time getting it back on
 

findinghomer

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Change cables and two starters doing the same thing would tell me it's not an electrical problem.

Have you checked the level of your oil, is it correct?

Remove the plugs and see if it cranks the same
Yes, I have had the plugs out, when it still cranked slow, that's when I turned to the forums. I checked the oil oil looks good. I borrowed a new battery from my neighbor just to be sure it's not my batteries. Fully charged in 1 year old still won't turn. The only thing I haven't done is pull the outdrive. But before I do that I went ahead and ordered another starter. Just a couple things to note, the battery cables I made were out of 4 gauge wire not 2 gauge or zero gauge, but pretty sure the original ones were 6 gauge, at least the ones coming off of The switch were. And the starter that I put on was rated at 1.4kw not 1.7kw like the one I took off, so I went ahead and got another starter. Really hate changing that out too because it's difficult to get to but it's better than pulling the outdrive at this point lol. But I guess if three starters are still doing it, along with four different batteries a jump pack and jumper cables on a car, the only thing I got left is to pull the outdrive?
 

findinghomer

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Plugs look fine, maybe a tad rich but nothing to worry about
Could it have anything to do with the slave solenoid by the breaker?

This is just so hard to diagnose bc it happened out of nowhere, not coinciding with any particular incident. Ran fine all day and the next day, and then ran fine when I started it in the driveway got it to temperature, and then when I shut it off when I went to go start it is when I started having slow cranking out of the blue
 

nola mike

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1. Ignore the plugs, they aren't the problem
2. Pulling the outdrive is waaay easier than swapping the starter. Didn't see whether its a bravo or alpha, but still...
3. Didn't see how hard it is to turn by hand yet
4. Plugs out there should be very little load on that starter. 9.1v is low. Starter voltage should be the same as the battery at all times. This still smells like wiring to me. 2 more tests that you can do.
a) Run jumper cables from battery to starter (keep other wires on there)
b) Voltage drop test: Set DVM to DC volts. To test pos: Put one lead on batt pos, other end on starter pos (doesn't matter which lead goes where). Crank engine. DVM should show little/no voltage. If it's more, that means you have too much resistance between batt and starter. Test the ground side the same way.

Also, does the cranking speed up as it turns? Maybe time for a vid?
 
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