Batteries load tested ok but voltage dropping

Cubey

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Here's a shot of my doorjam sticker. Decoding it on the NHTSA site, the info lists it as having a 6.9.

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Thewespaul

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Maybe it was an incomplete vehicle that was built in 87, but didn't get an engine until 88? Kind of like ambulances and busses. For regular trucks, that's a 1988 model.
I do remember the title being for an incomplete vehicle, it had a custom welding bed on it and barely any miles.
 

Thewespaul

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Here's a shot of my doorjam sticker. Decoding it on the NHTSA site, the info lists it as having a 6.9.

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Definitely the best year of the 6.9 to have, and you have the open headgaskets too.
 

Cubey

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Maybe it was an incomplete vehicle that was built in 87, but didn't get an engine until 88? Kind of like ambulances and busses. For regular trucks, that's a 1988 model.

I had a very late built, "incomplete" 78 Dodge class B van with the round 78 headlights (79 changed to square) but it had 79 wire colors which changed from 78. Doing wiring repairs, I had to use the 79-83 wiring diagrams.
 

IDIBRONCO

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I do remember the title being for an incomplete vehicle, it had a custom welding bed on it and barely any miles.
This could very well explain it then. There's no telling what kind of crazy combinations were in the incomplete vehicles.
 

Cubey

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Definitely the best year of the 6.9 to have, and you have the open headgaskets too.

What's open headgaskets? I highly suspect I have the original, untouched engine. Transmission, no. It was rebuilt at least once.
 

Thewespaul

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The 7.3s received plugs in the gaskets to restrict coolant flow, loom up 7.3 Cooling Mod to get the full load down
 

IDIBRONCO

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The 7.3s received plugs in the gaskets to restrict coolant flow, loom up 7.3 Cooling Mod to get the full load down
No, they were just closed off in those corners from what I remember. I could be wrong on that since it's been several years since I've seen stock 7.3 head gaskets.
 

Thewespaul

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Yep regular freeze plugs and the passage is blocked off with a stainless plate in the head gasket, which is why you have to use the 6.9 headgasket if you do the mod
 

IDIBRONCO

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There's no plate in any of the aftermarket 7.3 head gaskets that I've seen. They're just solid gasket material across tha corners. The insert comes in the 6.9 head gaskets.
 

ABNORDY

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This gripe is similar to the one I have on my 88. The gripe has been coming on for a couple weeks, this weekend I was in a wrong gear going over the curb and stalled truck, and ended up with the A$$ end in the road and unable to restart. New Alternator (bench tested good when gripe began to come on), Batts load test good at 720 and 725 CCA on 650 CCA batts, new voltage regulator, system charging at 13.4 VDC, and starter about a year old. When trying to start vehicle now it will crank very slow with not enough to start Truck, "known good Batteries VDC 12.9 before crank 12 VDC after first try, Battery charge from 100 percent to 94 percent (unknown Amperage ) checked and clean cables and clamps. went under to check cable to starter, giggled wire from solenoid on starter (with key off) starter engaged (scared the crap outa me as the truck was in gear) charged batteries to no start. I think that the starter is bad simply because I kept loosing prime as there was an air leak in the fuel system, also IME, normally with dead/low batteries it would not have enough juice for the starter to engage into the fly wheel. What is the Opinion on this gripe?? Thanks
 
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The_Josh_Bear

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Assuming the alt is putting out 14.1v charging:
If you had been driving for more than a few min when you stalled and couldnt restart due to engine not turning over very fast at all then your batteries are hosed.

BUT if you cranked it over and the engine rolled fast but didnt catch you have a worn out IP woth a hot start condition. Pour a liter of room-temp water over the IP and try again, if it starts you need an IP rebuild.
 

ABNORDY

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Assuming the alt is putting out 14.1v charging:
If you had been driving for more than a few min when you stalled and couldnt restart due to engine not turning over very fast at all then your batteries are hosed.

BUT if you cranked it over and the engine rolled fast but didnt catch you have a worn out IP woth a hot start condition. Pour a liter of room-temp water over the IP and try again, if it starts you need an IP rebuild.


Drove from work, about 30 minutes or so. when I started it at work it was a sluggish start and had to use ether . This has been acting up for a week or so. Batteries had 12.4 VDC after stall.
 

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