7.3 thread continued?

Could be a bad gauge. Could be a bunch of little things compounding too. Not just boost leaks but low HPOP pressure or weak injectors too.
I think they are glowshift gauges. The fuel pressure one seems wonky. Lots of times it will say its low then show high. Im sure the hpop and injectors are originals. I just replaced the mechanical fuel pump with a made in China Motorcrap a few months ago. (Not happy about that.)

As of now the glowplugs seem to have stopped working. It will not start without ether even on a warm day for the first start. Its almost like it isn’t firing at all. It used to at least smoke while trying to start and eventually it would. Now it will crank till the batteries die. If I give it a small squirt it will fire right up and will start no problem the rest of the day.

I have the glowplugs solenoid unplugged. I just replaced all that stuff a couple years ago less than 5000 miles ago. I will look into it later.

I dont think about working on it till I need to drive it and I have only driven it lately if I need to pull a trailer which it has been hooked up to for several months now.
 
They are stock. I have not noticed a leak. I would hear an exhaust leak and see black around a leak wouldn’t I? I will crawl around there and see.
You wont hear it unless its really bad. It dont take much to lose alot of drive pressure. Look for soot around the connections upper and lower. wont necessarily see it on the firewall.
This 97 was way down on boost/power with stock fueling.
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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.
Personally I dont think its the boost that takes out the head gaskets as much as it is the drive pressure. If you are running 30psi boost with 30psi of exhaust back pressure you have a pretty free flowing system. When a motor doesnt have enough exhaust flow and is running something like a 30psi boost / 60psi ebp everything gets backed up, holds heat and cylinder pressure is increased. A singular boost number is vague if you dont know the pressure that is driving it.
 
Personally I dont think its the boost that takes out the head gaskets as much as it is the drive pressure. If you are running 30psi boost with 30psi of exhaust back pressure you have a pretty free flowing system. When a motor doesnt have enough exhaust flow and is running something like a 30psi boost / 60psi ebp everything gets backed up, holds heat and cylinder pressure is increased. A singular boost number is vague if you dont know the pressure that is driving it.
Agree, that combined with ****ty tuning (timing)
 
Personally I dont think its the boost that takes out the head gaskets as much as it is the drive pressure. If you are running 30psi boost with 30psi of exhaust back pressure you have a pretty free flowing system. When a motor doesnt have enough exhaust flow and is running something like a 30psi boost / 60psi ebp everything gets backed up, holds heat and cylinder pressure is increased. A singular boost number is vague if you dont know the pressure that is driving it.
So how are you getting around the 25psi limit, tuning?
 
Personally I dont think its the boost that takes out the head gaskets as much as it is the drive pressure. If you are running 30psi boost with 30psi of exhaust back pressure you have a pretty free flowing system. When a motor doesnt have enough exhaust flow and is running something like a 30psi boost / 60psi ebp everything gets backed up, holds heat and cylinder pressure is increased. A singular boost number is vague if you dont know the pressure that is driving it.

How do I determine my back pressure then? Another guage?
 
I think they are glowshift gauges. The fuel pressure one seems wonky. Lots of times it will say its low then show high. Im sure the hpop and injectors are originals. I just replaced the mechanical fuel pump with a made in China Motorcrap a few months ago. (Not happy about that.)

As of now the glowplugs seem to have stopped working. It will not start without ether even on a warm day for the first start. Its almost like it isn’t firing at all. It used to at least smoke while trying to start and eventually it would. Now it will crank till the batteries die. If I give it a small squirt it will fire right up and will start no problem the rest of the day.

I have the glowplugs solenoid unplugged. I just replaced all that stuff a couple years ago less than 5000 miles ago. I will look into it later.

I dont think about working on it till I need to drive it and I have only driven it lately if I need to pull a trailer which it has been hooked up to for several months now.
Glowshift is not exactly known for being the best of quality, so could be a gauging issue. My fuel pump is only maybe 5 years old and is alrady failing again, so not much faith in the cheap fuel pumps out there these days. HPOP you could verify just by plugging in a scanner and seeing what the ICP and the IPR values are.


Id probably fix those glow plugs, ether isnt the best for a 7.3, and if those glow plugs swell youll be pulling heads to replace em.
 
Glowshift is not exactly known for being the best of quality, so could be a gauging issue. My fuel pump is only maybe 5 years old and is alrady failing again, so not much faith in the cheap fuel pumps out there these days. HPOP you could verify just by plugging in a scanner and seeing what the ICP and the IPR values are.


Id probably fix those glow plugs, ether isnt the best for a 7.3, and if those glow plugs swell youll be pulling heads to replace em.
Yes I should just spend the money on some Isspro’s.

I have Forscan so I will see what the readings are on it. When I couldn’t get it to start I did an injector buzz test with the Forscan and it said it passed but who knows if that means anything.

I replaced the entire engine wire harness, glowplug solenoid and the glowplugs with motorcraft parts. I replaced the under valvecover harness with a dorman kit. Maybe I should have bit the bullet and got motorcraft for that too.

I need to put a voltage meter on it and see what its doing if anything.
 
Yes I should just spend the money on some Isspro’s.

I have Forscan so I will see what the readings are on it. When I couldn’t get it to start I did an injector buzz test with the Forscan and it said it passed but who knows if that means anything.

I replaced the entire engine wire harness, glowplug solenoid and the glowplugs with motorcraft parts. I replaced the under valvecover harness with a dorman kit. Maybe I should have bit the bullet and got motorcraft for that too.

I need to put a voltage meter on it and see what its doing if anything.
Hard starting in my opinion is typically injectors. Billowing white smoke while cranking is a tell tale sign in my experience. I’ve replaced a few sets and fixed non-starting trucks.

I had a friend that didn’t want to spend the money, he ran hot shots secret all summer and his hard starting went away without injector replacement. It made me a believer.
 
Hard starting in my opinion is typically injectors. Billowing white smoke while cranking is a tell tale sign in my experience. I’ve replaced a few sets and fixed non-starting trucks.

I had a friend that didn’t want to spend the money, he ran hot shots secret all summer and his hard starting went away without injector replacement. It made me a believer.
It used to do that before I fixed the glow plugs. Now it does not smoke at all while cranking. Made me think they were not working at all.

I was driving it every day for 4 days in a row. It would fire right up after sitting for a month or more. The 3rd day in the row it just wouldn’t start. Since then it will only start with ether for the first start of the day.
 
Could be glow plugs not running. See if you hear the relay clicking. If so check voltage drop across the relay itself- if it's a half volt or more replace the relay. From there you can ohm out the individual glow plugs at the valve cover harness. I swapped from the OBS valve cover gasket + UVCHs to the Superduty style on mine because the OBS ones are known for melting the pins for the glow plugs.


I'd still check your ICP & IPR values. Seems unlikely, but maybe the HPOP is bleeding off after sitting for a while, and it has to re-prime and build pressure before the injectors will fire.
 
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It used to do that before I fixed the glow plugs. Now it does not smoke at all while cranking. Made me think they were not working at all.

I was driving it every day for 4 days in a row. It would fire right up after sitting for a month or more. The 3rd day in the row it just wouldn’t start. Since then it will only start with ether for the first start of the day.
Sorry, absolutely verify the glow plugs are working before replacing any injectors.

I’m speaking of trucks that had 100% operational glow plugs, and no starts below 35*.
 
What's everyone's oil and filter of choice for the 7.3? Stick with Motorcraft 15-40 and a FL1995A @ 5k miles? (Bonus: available at walmart cheaper than most online sources.) Or some other synthetic/blend like T6, Delco, etc, or even just plain old T4? Somehow T6 or Delco blend and a decent, non-oem filter ends up being a good $30-40 cheaper per oil change.
 
I'm still running the FL1995A. Oil is Rotella T4 15w40.
Thinking about doing a bypass oil filter next year though.
 
I run the Fleetguard LF9027 and Currently running Citgo 5w-40 Full synthetic Diesel oil.

Recomend the fleetgaurd to anyone. It is full flow with built in bypass and you can get them cheap depending on where you shop.

Fleetguard | Fleetguard
 
You wont hear it unless its really bad. It dont take much to lose alot of drive pressure. Look for soot around the connections upper and lower. wont necessarily see it on the firewall.
This 97 was way down on boost/power with stock fueling.
IMG_8885.jpg

IMG_8883.jpg

IMG_9467.jpg
Clean truck. I had to torch the uppipe bolts on mine.

What a pain!
 
I went with a 1995 and T4 for this round. I'll probably do more research for future changes.


When the fl1995 jumped over $20 i switched to baldwin and wix
I used to be all about Wix when you got mostly made in USA filters.....or, actually, I bought NAPA filters that were rebadged USA wix. But then Napa dropped wix in '23 and switched to Mann+Hummel and it seemed like almost all of those were made in China too.
 
I tried synthetic in my 97. Only difference I noticed was my wallet was lighter.
The switch from 1995 to 1995A sucks
 
What's everyone's oil and filter of choice for the 7.3? Stick with Motorcraft 15-40 and a FL1995A @ 5k miles? (Bonus: available at walmart cheaper than most online sources.) Or some other synthetic/blend like T6, Delco, etc, or even just plain old T4? Somehow T6 or Delco blend and a decent, non-oem filter ends up being a good $30-40 cheaper per oil change.
Heui really likes good oil, anti foaming etc.

That's all I got.
 
I run the Fleetguard LF9027 and Currently running Citgo 5w-40 Full synthetic Diesel oil.

Recomend the fleetgaurd to anyone. It is full flow with built in bypass and you can get them cheap depending on where you shop.

Fleetguard | Fleetguard

Honest questions.

I know everyone says the FL1995A sucks compared to the FL1995, but i dont know why? The only thing i can find is a change to the gasket.

Also: That Fleetguard is 30 microns whereas the Motorcraft is supposed to be 18 or 20, so what makes the Fleetguard better?
 
Honest questions.

I know everyone says the FL1995A sucks compared to the FL1995, but i dont know why? The only thing i can find is a change to the gasket.

Also: That Fleetguard is 30 microns whereas the Motorcraft is supposed to be 18 or 20, so what makes the Fleetguard better?
Great question. I went to a class years ago, like mid to late 90s, when this series filter came out. The venturi style, or vortex or whatever they call it with stratapore.

Seeing the testing results, videos, slide shows It was impressive. At that time the only way you could get bypass filtration was an add on filter. Anyone remember the old lubrifiner filters that were like 2 gallons of oil mounted on a crossmember that were the messiest things in the world to change?
Well I do.

These filters stop sludge. They work as well as a separate add on bypass filter. Cummins ran 3 engines, one standard filters, one with standard filters and an add on bypass and this filter here.
They ran the engines with an electric motor, so no risk of fuel contamination, or failed injectors or anything like that. About as fair and equal as you could run a test.
They all had the same oil and oil change intervals. Cummins pulled the valve covers and oil pans every 500 hours for inspection. In time lapse you could see the sludge forming. Really cool thing to watch.
Of course standard filters failed first. Oil supply related issues, I honestly don't remember which of the other two engines failed second but when you open them up they both looked like brand new inside. They did not die from oil supply related failures.

To me that showed we can get bypass filtration without adding on bypass filter, without the addition cost and mess.

Secondly, have you ever seen a hole blown in the filter media from thick oil and high pressure on a cold start? Not nearly as much of an issue today with all the synthetics but it used to be a very serious issue. If you were watching the gauge you could see it happen, big drop in oil pressure, like from 80 psi to 50 instantly, we tried to save engines after that, but it was not easy, pulling pans, changing oil pumps, trying to flush the systems. Mediocre results.

Now onto the micron rating. Yeah I would agree that 18 microns would filter better than 30. But with that 30 you get a bypass filter. Also Big trucks use 30 micron, why does a pickup need less? Smaller microns?
Fleetguard is a filter company, it is all they do. They don't outsource filters. They make their own, now most of them in juarez Mexico. They are owned by cummins and come on cummins engines.
That gives me a pretty good feeling that they know what they are doing.

Everyone's experience is different. Wix really used to be top dog. But after all the years of quality issues at work and in personal life I can say I have never had a bad fleetguard filter. No missing gaskets, no metal shavings inside a brand new filter, no rust inside a brand new filter. No bad check balls inside brand new filters. Probably plenty of other reasons I don't even remember.

TMC a fair sized trucking company is located in Des Moines. They were having problems with lubrifiner brand filters on cummins engines. They had oil filters falling off while driving down the road. It got so bad that the shop was sending guys out to tighten every filter on every truck every week. Of course filter guys say it is a cummins problem and cummins was saying it was a filter problem. But TMC is big, they carry some weight.
Cummins guy finally says hey, try fleetguard, since we own fleetgaurd, if a filter falls off it is still our problem.
So TMC did, they swapped to fleetguard. No more filters fell off, came loose. No more problems. On top of that, they greatly reduced the number of oil leaks they had. (which were caused by filters cut wrong apparently)

If you take your 444E to an international dealer for service they are putting on a 30 micron filter.

Now my kids tell me I am crazy and they only buy motorcraft oil and filters. So even though Ford didn't make the engine, they think Ford knows best what filter should be on it.

Yeah I rambled there. Anyway in my mind that fleetguard is the best filter for the old 7.3 unless you want to add a separate bypass filter.
If you add a separate bypass filter then it really doesn't mater what you throw on there.
 
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