Diesel engine rpm

Hi,

I am well aware of that, I just see "short out" as a term to short circuit an electrical item.

I am sure I am not alone in this.

I see your point. But that phrase has probably been used since before I was born. At the very least I know a DD mechanic who used it that has been working on them that long

....X2....

Bet you are overpropped or the props need tuning not the engines.

Hi,

In post No 18 the OP says he could not get to full no load RPM, I don't think the props have anything to do with the no load RPM,do you?

What the OP hasn't said is if this is always the same engine he is measuring, I have never seen two diesel engines that will run at the exact same RPM, there is always a couple of RPM Different.

The problems with the lack of RPM could be as simple as a loss of adjustment in the throttle linkage/control.

A Top Tune on a 6 71 is not a major event and as I wrote previously two stroke Detriots are an engine family that always seems to respond well to this little bit of TLC.

I agree. It sounds like a governer adjustment or throttle cable adjustment at the very least. I too have seen tune-ups or top end adjustments as a necessity on DD's to keep them producing their rated power. I also have seen a mechanic do 8v71's and it took him about 1.5 hours per engine (although he was probably the best DD mechanic Ive seen). I think DD recommends this every 500 hours. I know with CATS they are part of the 1000 hour service on most and every 500 hours on some (c-18 E)

Checking for full throttle is easy. Put your throttle control in full position, then see if you can move the throttle arm connected to the governor any further. If you can adjust, if not you might want to adjust your no load rpm. But if you decide to go under the cover, first set the governor settings under the governor cover, just please make sure you back off the buffer screw. Once those settings are correct, then make the necessary adjustments under the valve cover. From past experience (30+ years) a majority of the these adjustments are by feel. One thing not in previous posts that I noticed, was no mention of fuel psi. That should also be checked.

Hi,

That is exactly what I meant.

The next Posters suggestion of verifying the Fuel Pressure is a good one too.

Hi,

I should have added that a 6 71 and most other diesel engines can do their rated no load RPM under no load with a lot less fuel at and no load compared to what they want at full load

Sir: As a Detroit Diesel Corporation Certified Overhaul & Repair Technician I must take exception to your comments about adjustments within the governor, and under the valve cover.

1) Removal of a governor cover by an inexperienced and untrained person is
an invitation to a runaway engine when it is subsequently started.
Only formally trained and experienced Detroit technicians should remove a
governor cover, or work on any of the governor's internal adjustments.

2) There are NO, zero, adjustments within the governor, or under the valve
cover that are correctly adjustable by feel.

Your post amounts to reckless endangerment of readers not knowledgeable
in safety issues associated with Detroit governors, fuel systems and valve
trains.

Ron,
If you think for one minute my post was reckless. You are wrong. I never suggested that anyone perform any kind of work on these engines, that is not totally familiar or qualified with them. I have seen a few engines run away in my time, and people loose fingers. I to am a certified Detroit Diesel Tech. The OP was looking for advise. That's merelyall I gave.

Parsing your words after posting them does not alter their content.
Your post was absent of warnings / guidance to a reader concerning lack of engine controlability / runaway, and separation of flywheel hazards resulting from failure to understand and perform basic safety procedures and checks during governor and fuel system adjustments. It was also factually incorrect.

In short, you provided enough misinformation to induce a reader acting on your post to unknowingly endanger his physical safety, and that of others.
Further elaboration is unnecessary to substantiate this reality.

In partial defense of Jimbo, and from my limited experience of observing the guys twisting the wrenches, one can [correctly] adjust the buffer screw on a Detroit...by listening.

The idle goes from RUMrumRUMrumRUMrum to...Rummmmmmmmmmm.