So mines not supposed to do this?
- Thread starter chris142
- Start date
going so fast the speedo went all the way around!
Hydro-idi
Full Access Member
Are you talking about the rpm limit or is your tach gauge going wacky?
My 6.9 would easily hit that rpm at wot, once getting it to 4K. They can handle it.
If your gauge is going loco, replace the sensor that’s on top of the IP tower cover.
My 6.9 would easily hit that rpm at wot, once getting it to 4K. They can handle it.
If your gauge is going loco, replace the sensor that’s on top of the IP tower cover.
FordGuy100
Registered User
3800 rpm governor spring, if factory and or not adjusted. Mine has a 3300 rpm spring, but will free rev to 3500
Not wacky. Actual rpm.
Hydro-idi
Full Access Member
Wouldn’t be concerned with that rpm. It’ll run wound up like that all day long
It all depends on pump wear. Even if your pump has been rebuilt doesn’t mean the governor spring has been replaced. The gov spring is under constant tension and as it contracts over time is looses spring pressure and your governored rpm decreases. Which is good, considering the old Bosch pumps did the opposite..... but these springs should be replaced with every rebuild, but I almost always see the original spring there. Doesn’t work as good as it did 25-35 years ago.
YJMike92
Full Access Member
I've been wondering about low RPM on mine. Max RPM about 3300. I haven't had time to investigate. I'm not sure about the pump's history. 129k on the truck.
If you adjust the minimax inward you can get more tension on the main spring, this will increase fuel across the board marginally but will move the fuel higher into the rpm range where it’s needed as well as increase your governed rpm.
YJMike92
Full Access Member
Thanks,
If I can ever get caught up in the shop I hope to spend some time on the truck. Just received my new timing meter today. I figure I'll start there for some kind of baseline before doing too much else. I'd like a junk pump just tinker a little.
ttman4
Last Nite's Dream..
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Since I bought my first 7.3 in ‘90 I have always had a problem with high diesel rpm’s for some reason. It is just been hard for me to get used to running a diesel with high rpm’s. Even today. I am and old school truck driver from the late 60s, 70s, 80s and trucks were worked roughly 18 to 2200-2300 RPM mostly. Sometimes 2400 if we were running from the cops 
But what I am saying I learned Back then on Cummins, Cat, Detroit, MAC using a lower RPMs, and it still gives me trouble to pull mine up to 2800 or more RPMs. Probably a mental problem ha ha Ran a Cummings 903 v8 one trip and they told me work it 2800-3400 rpm....was hard for me!!!
But what I am saying I learned Back then on Cummins, Cat, Detroit, MAC using a lower RPMs, and it still gives me trouble to pull mine up to 2800 or more RPMs. Probably a mental problem ha ha Ran a Cummings 903 v8 one trip and they told me work it 2800-3400 rpm....was hard for me!!!
It seems most worry about running a diesel over about 2500 rpm. I know this is a bit of apples to oranges comparison, but here is a run after a repair on my 6.0. It’s 100% stock tuned, only mod is an egr delete. It’s a 5R110 automatic. This was a roll into the throttle and let it do what it wanted.
https://www.facebook.com/100003462468852/posts/272949086127214/
Sorry if you don’t do Facebook.....
Even on my IDI, the C-6 likes to shift at 2500ish, even if I’m not pushing it. Maybe the VRV needs adjusting, but that’s how it’s set now.
https://www.facebook.com/100003462468852/posts/272949086127214/
Sorry if you don’t do Facebook.....
Even on my IDI, the C-6 likes to shift at 2500ish, even if I’m not pushing it. Maybe the VRV needs adjusting, but that’s how it’s set now.
Yeah I learned stick on a dt466 truck so even my gassers don't usually get spun past 2500rpm purely out of habit. The good news is when I actually do wind them up I'm pleasantly surprised by the extra power lol!
Kevo1288
Full Access Member
Since I bought my first 7.3 in ‘90 I have always had a problem with high diesel rpm’s for some reason. It is just been hard for me to get used to running a diesel with high rpm’s. Even today. I am and old school truck driver from the late 60s, 70s, 80s and trucks were worked roughly 18 to 2200-2300 RPM mostly. Sometimes 2400 if we were running from the cops
My daily commute to and from work my truck literally only goes to about 1800-1900 tops. Its all back roads 30-50 mph range. I do open her up a few days a week to get it working through all rpm ranges but im with ya, I cringe sometimes when I hit 3000 lmao
