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  #1  
Old 07-29-2017, 02:35 AM
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JoeDirt JoeDirt is offline
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Default No rev limiter?

My tranny shifts really late (or not at all) if I don't let up on the gas pedal.
RPM goes waaay over 4000, even 5500 once when I was not paying attention.
A while ago I gave my TV cable a little more slack and the shifting improved.
I rode around like that for a few months but after reading a lot of stories about how you can ruin your tranny if the cable is not set right I adjusted it back.
(pulled all the way to the firewall then hit the gas)
Immediately the late shifts are back (duh) but it makes me wonder, shouldn't my IP limit my maximum revs?

O and for the yearly emission test, they have to mash the gas for 5 seconds while in neutral, they almost blew up my engine!
My revs really need to be limited, I don't think my car will survive another emission test.
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Old 07-29-2017, 09:28 AM
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DmaxMaverick DmaxMaverick is offline
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To begin, change the fuel filter and/or fix your fuel supply system shortfall (this fixes 99% of these complaints).

If you are, in fact, seeing 4000-5500 RPM's, especially under any appreciable load, the IP is broken, or your method of measuring engine speed is highly questionable. The IP governs maximum speed, but reduces (tapers) fuel volume beginning about 3100 RPM's. Governed speed should never exceed 3600 RPM's. Late shifts at high RPM's is either a failed transmission, TV and/or cable, or you need to change the fuel filter. This assuming everything worked normally before something changed.
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Old 07-29-2017, 09:32 AM
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I already replaced the fuel filter some time ago.
I can repair the late shifts by adjusting the TV cable again I think.
That leaves the IP right? Can I somehow check the governor or something?
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Old 07-29-2017, 11:03 AM
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Simply, if the engine speed is exceeding 3600 RPM's (verified), then the IP governor isn't working. A failed governor is a broken IP.

Even if you have a relatively fresh fuel filter, verify fuel delivery to the IP. Poor quality fuel can foul a filter quickly, and there may also be other issues with fuel delivery, including a failed/failing fuel lift pump, air leaks, collapsed fuel lines, or other restrictions. Any shortfall in the fuel delivery can, and usually does, cause tranny shifting issues. It's a simple matter of the engine power output (reduced) compared to the throttle (valve) position causing delayed, higher RPM shifts.

Adjusting the TV cable to accommodate other issues can damage the transmission. Adjust the cable correctly, then correct other issues that cause problems.
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Old 07-30-2017, 05:33 AM
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I checked the fuel delivery to the pump, I saw nothing out of the order everything clean and no leaks.
Tried readjusting the TV cable and I found out that if I slide the slider all the way to the firewall it becomes stuck, it will not adjust when giving full throttle.
So I tried again this time with the adjuster just a VERY small tad back and when moving the throttle lever to WOT it clicked so I assume it adjusted itself this time.
Anyway the shifting is back to normal again, not too soft shifts not too hard and all at the right moments depending on throttle position.

Still have that problem with the unlimited RPM's though so I'm going to have my pump checked or buy a new one.
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Old 08-10-2017, 11:06 PM
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I talked to a friend who used to own a ex-military Chevy K30 and he had the exact same problem, his revs weren't limited either.
When going through a emissions test he had to block the throttle lever with a piece of wood to prevent over revving the engine.

None of you ever had this problem? I find it kinda strange I don't read anything about this on the diesel page and the only guy I know who owned a GM 6.2 diesel had it too.
This must be a common problem, or is it the Dutch air or something in the water that make our pumps go crazy??
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Old 08-10-2017, 11:15 PM
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It's not a rare thing, but it's the thing that happens right before the rest of the pump eats itself. If it's broken inside, it's just a matter of time. I've seen it plenty of times. Usually, the pump is rebuilt before it destroys the core. You can run it until it does, but then you won't have a usable core to rebuild. How long that is, is hard to say. Miles, months, years. I don't know, but....
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Old 10-09-2017, 02:30 PM
CryHavocc CryHavocc is offline
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Default I also have this problem

I have a 1984 k10 with 137k on the clock and a TH400. I just got my truck back together after installing a new fuel tank and a tach. I calibrated the tach with a cheap laser off ebay. I'm using a autometer diesel tach that runs off the alternator fields. meter was reading about 930 at idle. I set the tach at that and checked it at 2k and 3k and it seemed good. My whole reason for installing the tach was going down the highway at say 65 to 70 the motor seems to be screaming. now with the installed tach I can confirm it was @ 65 turns about 3k. push it more and it will go to 4500 or so @ 75 mph. also with the installed tach it gets me the ability to figure out what my gears are in the rear end (with out taking off the cover) and they should be 4.11's.

so now assuming that the flea bay meter and tach are set up correctly and my 6.2 had a properly working gouverneur it should have been cut out @ 3600? I need to get rid of the square filter and install a spin on filter setup and that's next on the list. Any recommendations for IP's filter setups?
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