7.3 thread continued?

How long? The book isn't quite accurate - some of calibrations vary the time and some don't.
My old 96 PCM ran the glow plugs for a different length of time than my 97 PCM did. Both stone cold were 3 minutes, but the 97 would reduce the duration based on engine temp (once fully warmed up they don't cycle at all), whereas the 96 would turn them on for the full duration every time you cycled the key regardless of engine temp.

I'm not sure, seemed like I waited 3-4 mins? I need to do some more testing, but was more concerned with other things.

I don't know how much current the grid heater pulls, but it can't be more than the glow plugs.

That's what I thought, but depending where you read, it's 190-220 amps :eek:
 
Anyone know where this goes? I think I got the other vacuum hoses hooked up right, but can see what this would go to.
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That's the washer pump line.

Be gentle with it, they like to crack at this age and it's always just under the cowl where you cant reach it to sleeve it with hose :laughing:
 
I think I found my cruise control problem. Sometimes I just randomly try it just because. Today it was raining and I hit the on and set button at 55 and it set. I drove about 5 miles then the speed limit changed and I hit accel up to 70 and it worked perfectly. Once I got into a town I had to kick it off with the brake and it reset after that. Then I had to stop at a light and it didn’t work again after that. I kicked the clutch pedal in a couple times and it worked again. The next light I could never get it to work again.

I assume it is the clutch switch. I looked under the dash and didn’t see a switch on the pedal. It must be underneath. I wasn’t going to lay in the water today to find out. I do know the truck wont start unless your foot is all the way to the floor on the clutch pedal so I assumed the switch was fine. Now im not so sure. Is there a way to bypass it, and would that make my cruise work assuming it is the switchs fault?
 
I think I found my cruise control problem. Sometimes I just randomly try it just because. Today it was raining and I hit the on and set button at 55 and it set. I drove about 5 miles then the speed limit changed and I hit accel up to 70 and it worked perfectly. Once I got into a town I had to kick it off with the brake and it reset after that. Then I had to stop at a light and it didn’t work again after that. I kicked the clutch pedal in a couple times and it worked again. The next light I could never get it to work again.

I assume it is the clutch switch. I looked under the dash and didn’t see a switch on the pedal. It must be underneath. I wasn’t going to lay in the water today to find out. I do know the truck wont start unless your foot is all the way to the floor on the clutch pedal so I assumed the switch was fine. Now im not so sure. Is there a way to bypass it, and would that make my cruise work assuming it is the switchs fault?

I think there is 2 switches because from what I remember the cruise will kick off as soon as you touch the clutch. But ya, I'd start there.

Does your brake light on the dash work? Like when the parking brake is on?
 
The manual and auto trucks use the same dash harness, the autos just have a bypass plug in the harness. So you could grab one out of a junkyard truck and plug it in to test.

IIRC there is only one switch on the clutch pedal but I think it cuts multiple circuits. I'd have to go look at the book again. On the diesel trucks the pressure switch in the master is the one that disables the cruise, not the brake pedal sensor.
 
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The manual and auto trucks use the same dash harness, the autos just have a bypass plug in the harness. So you could grab one out of a junkyard truck and plug it in to test.

IIRC there is only one switch on the clutch pedal but I think it cuts multiple circuits. I'd have to go look at the book again. On the diesel trucks the pressure switch in the master is the one that disables the cruise, not the brake pedal sensor.
It uses the brake pedal switch as well. I don't have a cruise master cylinder (so without that pressure switch) and cruise that I added works fine.
I just had to jumper that plug.
 
Yeah that was the big recall on the gas engines. The diaphragm would fail letting brake fluid into the switch, shorting it and causing a fire. It's why they come with a fusible link now.

The gassers were fed by a fuse that was hot at all times, that's why people were coming home to their houses burned down. On the diesels they were fed by a key hot fuse instead.
 
I would like to just jump all the switch’s except maybe the brake pedal switch.

Right after I posted earlier saying the truck wont start without the clutch pressed in. I went out and it started without pressing the clutch in. I know for a fact it wouldn’t start the other day without the clutch pedal pressed. So it seems the switch must be sticking or shorting out.
 
Spent the last 7 years running all different sizes of T4 turbos in my 2001 F350. Nothing fancy, stock injectors, 80hp tune, foot to the floor driving style. Over the summer I decided to try out an S362sxe from BorgWarner. This is one of the smallest in the SXE lineup and on paper is only slightly larger than the stock gtp38. Compressor inducer on the 362 is 61.44mm (stock is 60mm) and the turbine wheels share the same dimensions (76mm/68mm). The dimensions are the same but the blade geometry is much different. I used the smallest twin scroll T4 housing I could find which happened to be a .83ar. This is the fastest spooling, cleanest running, most fun to drive turbo I have ran to date. Previously I had ran a similar S363/.83 that I thought was great. The s363 made a whopping 42psi boost with egts that barely registered over 1100 degrees. I have a feeling the 362 will beable to comfortably make around 45psi of boost. With stock 140cc injectors this is pretty much unheard of in the 7.3 world. Even though boost is just a measurement of restriction it does shed light as to how much air is being moved. For example a fully modified stock turbo (billet wheels,etc) with the same tune limits out at around 32-34psi. No changes but the turbo and picking up 10psi is quite the change. I will say the only draw back is that it is always making a lot of boost. Towing a decent trailer down the highway on flat ground will net a consistent boost level of around 25psi @ 65-70mph. Any incline and you are hanging around 30psi+. RPM down below 2000, say 17-1800rpm it runs 25psi+ no problem and virtually no smoke.
 
Spent the last 7 years running all different sizes of T4 turbos in my 2001 F350. Nothing fancy, stock injectors, 80hp tune, foot to the floor driving style. Over the summer I decided to try out an S362sxe from BorgWarner. This is one of the smallest in the SXE lineup and on paper is only slightly larger than the stock gtp38. Compressor inducer on the 362 is 61.44mm (stock is 60mm) and the turbine wheels share the same dimensions (76mm/68mm). The dimensions are the same but the blade geometry is much different. I used the smallest twin scroll T4 housing I could find which happened to be a .83ar. This is the fastest spooling, cleanest running, most fun to drive turbo I have ran to date. Previously I had ran a similar S363/.83 that I thought was great. The s363 made a whopping 42psi boost with egts that barely registered over 1100 degrees. I have a feeling the 362 will beable to comfortably make around 45psi of boost. With stock 140cc injectors this is pretty much unheard of in the 7.3 world. Even though boost is just a measurement of restriction it does shed light as to how much air is being moved. For example a fully modified stock turbo (billet wheels,etc) with the same tune limits out at around 32-34psi. No changes but the turbo and picking up 10psi is quite the change. I will say the only draw back is that it is always making a lot of boost. Towing a decent trailer down the highway on flat ground will net a consistent boost level of around 25psi @ 65-70mph. Any incline and you are hanging around 30psi+. RPM down below 2000, say 17-1800rpm it runs 25psi+ no problem and virtually no smoke.
Neat! Any idea on the drive pressures?
 
That's super cool. Would love to try it. Any idea why the .83AR on Irate Diesel's sight says "not recommended for 7.3L"?
 
Wow those are some pretty big boost numbers for such small injectors


Looks like im going to be going down the electric fuel conversion rabbit hole on my 96. Fuel bowl is full of aluminum shavings, i can only assume the mechanical fuel pump is imploding....
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Neat! Any idea on the drive pressures?
That's super cool. Would love to try it. Any idea why the .83AR on Irate Diesel's sight says "not recommended for 7.3L"?

Most of the companies that offer T4 kits recommend the 73mm turbine SXE for everything. I don’t know if many have even tried running a 68mm, let alone a .83ar housing. I’ve heard directly for aftermarket 7.3 turbo companies not to run the .83 as well. Sure you don’t want to run big injectors with a hot tune. It has it place, just like you don’t want to run an s369 towing 12k.


Here are a couple drive pressure videos with the 363/68/.83 back when the truck was automatic. First video is just an unloaded pull. Boost is left, EBP on the right.



Heres towing a 12.5k 5th wheel. Don’t mind the kid coughing, lol. Could run 35psi foot to the floor forever. You really have to work to break 1200* egt.



 
Well I guess I need to figure out what is wrong. I dont think there are any boost leaks. There is not much in the way of connections with it being non intercooled. Who knows, it could be the Chinese gauges I have also. Or the turbo is tired it has 208k miles and is almost 30 years old.
 
Yeah, they do that. Ford never intended for them to see 24+ PSI.

Supposedly sustained 25-30 PSI will stretch the head bolts and pop a head gasket. Hasnt happened to me yet, but i try not to take it over 25 for extended periods of time. Stock turbo is pretty inefficient at 25PSI and causes high EGTs so i try not to stay there. WIth head studs i dont think you can hurt the motor below 40 PSI unless you run stupid high EGTs and melt a piston.
 
Well I guess I need to figure out what is wrong. I dont think there are any boost leaks. There is not much in the way of connections with it being non intercooled. Who knows, it could be the Chinese gauges I have also. Or the turbo is tired it has 208k miles and is almost 30 years old.
up-pipes the stock leaky kind?
 
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