Cat 330B / 3306 engine - governor adjustments...?

[MHDim]

Hello everybody, it's my first post here so I hope I'm doing everything correctly, pls don't feel offended. I hope in the future I can bring a modest contribution to the knowledge base of the forum, but now I'm in bad need of some help.

My problem is engine-related, but I didn't see any engine-specific section, so I'm posting it here since the engine is in a Cat 330B excavator (machine 3YR01089, eng. 13Z48066).

Has anybody ever performed the adjustment procedures for the 3306 engine's fuel injection pump governor? (inline-6, direct injection, in-line Cat fuel injection pump)
Same question goes for a 3304, which I'm guessing should be roughly the same, since it's a basically similar engine, only it's an inline-4.

I have (almost) all dedicated tools, I have access to SIS, I'm familiar with Cat equipment / been working on them since 2003, but I just can't get any conclusive results. At this point it's one of three cases:
1) either I am an idiot (which can never be 100% ruled out)
2) or there are some mistakes in the procedure described in SIS
3) OR, there is something so badly messed up in this governor, that it's a wonder that the engine still runs.

The procedure itself is rather long, and my problems are pretty complicated, so since I don't want to be annoying with a wall of text in my first post, I will leave it like this for now. If anybody thinks they can help, I will dive into details (which, I repeat, will be long and potentially boring, sorry in advance about that).

Many thanks in advance!

 

[heymccall]

When you say "governor", are you referring to inside the end of the pump, or the electric controlled part?


Seeing how it's a 330b, does it have factory auxiliary hydraulics, with the auxiliary computer by the air filter housing? I don't see it under the serial number, but, I had a 322b that didn't list it (auxiliary hydraulics) under the serial number.

 

[MHDim]

By "governor" I mean the mechanical regulator which - yes - is in the rear of the fuel injection pump. Injection is 100% mechanical, the only electric part is the fuel shut-off solenoid, which is used for starting & stopping the engine. I am trying to perform the adjustment procedures given in SIS for the fuel setting, air-fuel ratio control etc, but am getting confusing results - basically, almost nothing happens as the procedure says it should. I will try to go into details, maybe later today, but pls be warned that it will be annoyingly long...

And yes, the machine has one-way auxiliary hydraulics, with the auxiliary computer (small rectangular one, with red digits on the display), near the air filters and the relay/breaker panel, behind the cab. They are factory installed and they do show up under the correct serial number, which is 3YR01079 (not *89 as I've written before - sorry for the typo )

 

[Junkyard]

Original motor to the machine? There are so many variants of the 3306 maybe it's been swapped.....I saw you posted the engine S/N, just verifying it matches.

Give us some examples of what is not happening like SIS says it should. Condensed version is fine for now

 

[MHDim]

Thanks for your replies. Here are some details, I will try to keep it condensed (don't know if I can, though...)
First, some background details: 99% sure it's the original engine; the machine has been with its current owner since 2005-2006 and they never swapped it. It doesn't have the engine ID plate, but unlikely it's been swapped during the first 5 years of the machine's life. It worked fine until 7-8 months ago, when the engine started to lack power (this is what I've been told). The owner changed the injectors (with genuine Cat replacements) in autumn 2017, but the lack of power persisted. They took the fuel injection pump to a local pump repair shop, that messed about with it for a couple weeks, then returned it. It was put back on the engine... and still no power.

This is the point where I took over; indeed, in boom priority mode + power mode activated, engine speed dial on 10, under full load it dropped to ~1300 rpm, which is unacceptable.

I ruled out everything concerning hydraulics (performed pump flow tests using the 4C9910 flowmeter, checked all circuits related to NFC and power shift pressure - everything is fine). On a hunch, I took apart the FRC (fuel ratio control) module from the very rear of the injection pump, and sure enough, found a damaged / perforated 6I1564 diaphragm, which was a clear problem, as in my reasoning, it's effectively leaking boost pressure through there (not the first time I see this problem). So I replaced it.
Now the power is kinda OK(-ish...), meaning that with the speed dial on 10, boom priority + power mode on, it stays at 1800 rpm... but at lower positions of the speed dial, it still lacks power; moreover, it blows a generous amount of greyish smoke, which definitely does NOT smell like oil... rather, it kinda smells like unburnt diesel fuel.

Suggestions are, again, welcome... but, since I know the pump/governor has been tampered with, it seemed logical to me, that the first step is to rule out any wrong setting / misadjustment. Therefore I tried following the procedures in SIS... and only got 2 full days of frustration

I will return with my setting-related problems in the next post, thanks for reading so far...

 

[MHDim]

So, further details follow. I attach the procedure, extracted from SIS in a PDF document. Not sure if I'm allowed to post this document here; if not, I kindly ask that the moderators delete it (or let me know about it, and I'll delete it myself) - I don't want to start off on the wrong foot here...

My first issue is at the first section - Governor Adjustment for Fuel Ratio Control Linkage. All tooling - which is genuine CAT - is correctly installed, I have correctly found the zero rack position, all goes well until step 14 (page 8). The first question arises at step 14b ("ensure that the end of the [6V2017] tool is behind the governor linkage"). Now, I might be stupid as I said, but after trying it 100+ times, the only way that I can possibly engage the tool BEHIND the governor linkage seems to be by pulling the linkage itself to the rear of the pump enclosure, which results in a movement of the fuel rack, recorded by the dial indicator as approx. 3 mm away from the "zero rack" position.
Question 1: Is this normal? The procedure says nothing about it...

Second issue is at steps 16-17 of the same section, which state:
"16. Turn the spring clockwise until the indicator hand stops moving. This is the Static Fuel
Ratio Control Lever Setting.
17. Now, slowly turn the rod counterclockwise until the indicator hands stop moving. This is
the Static Fuel Ratio Control Lever Setting."

Question 2: what SPRING shall I turn at step 16? The only thing I can turn after mounting all the hardware is the threaded ROD which goes through the knurled/threaded collar of the 6V7941 spring compressor tool...

At this time, as I start to slowly turn the rod of the 6V7941 tool, nothing happens for the first 7-8 turns, then the hands on the dial indicator start to turn, until they reach a reading of ~4.5mm - then they stop moving, even if I gently keep turning the tool. If I start to turn the tool backwards, again they stay still for a good few turns, then they slowly descend to a reading of approx. 3.7mm.
Question 3: How can I relate this to the information given in steps 16 & 17 of the procedure in SIS?

Question 4: (secondary) - this is related to the NOTE after step 17 in the SIS procedure, which states:
"There will be a small, initial amount of movement by the indicator hands. Then, the
indicator hands will stop moving while the rod is turned out for another 1 1/2 turns. Now,
the indicator hands will begin to move again. The indicator hands will follow the turning of
the rod until the setting is reached. Remember to turn the rod slowly so the rack can follow
the governor components."
In reality, in my case, nothing like this ever happens. Both when turning IN and turning OUT the compressor rod, the indicator hands are completely still for the first few turns, then they gradually move to what appears to be their final position. Again - is this normal? What is the SIS procedure talking about..?

Moving on - this machine has no Variable HP Solenoid, and (discouraged by the former results) for now I didn't even bother with the Fuel-Air Ratio Control and Governor Check, and the Fuel Ratio Control Adjustment.

What I did try was the Fuel Setting Procedure (starting/titled just at the bottom of page 18 in the attached document), and here, alas, I only found more questions than answers...

Again, all goes well until step 13 on page 25. From here, the following questions arise:
Question 5: (secondary) How should I determine if my governor is "WITH a torque spring" or "WITHOUT a torque spring"..? As I said, I'm generally familiar with Cat machines, as I've been working on them since 2003, but I'm not specifically an engine specialist...

Regardless of the answer to question 5, in any of the following steps, as I turn the rod of the spring compressor until the continuity tester light turns out, then backwards as it just turns on, the reading of the (*I hope!!) correctly installed dial indicator stays at 0.00 mm... the hands do not move at all throughout the procedure!

Question 6: what (if anything) am I doing wrong in the above paragraph? Am I that stupid...?

That's about it... again sorry it was so long, any other info is available if you should need it.

 

[Mark250]

hi just off track from the SIS procedures. but having said that the fuel pump was removed, did you verify that the static timing is correct and that the timing unit is functioning correctly. just my 2 cents worth
and from memory I have followed that procedure and was able to set up as detailed.
Mark

 

[Cmark]

Second what Mark250 said. Take the auto advance unit apart and check it.
Don't get too hung up on the governor settings. If you're getting diesel smoke then it looks like the pump's delivering.
Does it idle OK? If the low idle screw has been adjusted to stop the engine stalling, that can point to a worn pump camshaft which can also produce these symptoms.

Q5. Yes your machine does have a torque spring. Item #2.

 

[MHDim]

Yes, I noticed that this particular engine has the auto timing advance unit; I didn't check the actual timing, as I don't have the necessary tools. Honestly, I did think about taking it apart and visually / physically checking it... but I wanted to check everything else at first, since that's a rather big job. I'm not being lazy, I just tried to rule out the simpler things first

The engine idles well, in fact it sounds nice at any RPM, it's just that (a) it still appears to lack a bit of power at any rpm other than high idle, and (b) there's the grey smoke issue that I mentioned previously. Also (forgot to mention initially) starting is somewhat difficult if speed dial is below positions 3-4, then you have to crank it for a good 6-7 seconds to start. If the speed knob is placed at 4 or above, it does start immediately.

I know that the pump is delivering, in fact I was afraid that it's "delivering too much" in one way or another (fuel setting too high and/or fuel-air mixture too rich), hence my attempts at checking the governor (again - knowing it has been messed about with).

I'm currently checking my options, indeed I am considering dismantling the auto timing advance. Any other ideas/suggestions are welcome and highly appreciated!
(and thanks for all the advice given so far!)

 

[Cmark]

The static timing is simply a matter of inserting a 3/8" bolt into the flywheel and a 5/16" (3/8"?) drill bit shank into the pump camshaft and should probably be one of the first things to check.

Your comment about needing the governor control at 4 in order for the engine to start rings alarm bells. You need to find out if it's a problem with the governor actuator motor calibration or not. Disconnect the cable at the engine end and check the governor lever moves smoothly through its full travel. With the governor lever in the low idle position, the engine should start easily. If it doesn't, you have a problem in the pump/governor area. If it does, it may be simply that the lever isn't being actuated all the way. Try holding the governor lever fully open with a cable tie or something and see how the machine performs.

What's your high idle RPM?

How many hours on the machine?

Have you had any problems with bad fuel?

 

[Mobiltech]

I would start with fuel pressure and boost pressure check. Check pin to pin timing if pumps been off.

 

[MHDim]

First, thanks again for all your replies. What a nice community... as I previously said, hope I can also contribute here in the future.

Now - I know about the static timing, the 3/8" bolt in the flywheel and so on. For the pump camshaft, I have the genuine timing pin tool, that I guess is also 3/8", as when I don't have it on me, I'm using the shank of a 9 mm drill bit (since I'm in Europe... ). What I don't have are the 8T5300 & 8T5301 tool kits that are used for checking dynamic timing. From what I see, these tools should be mandatory if I were to check the correct functioning of the automatic timing advance unit without taking all the front gear apart...
It's true that in this case, I didn't really check if the pump is correctly installed as per the static timing procedure. The engine runs so smoothly (audibly), that the thought of an incorrect pump installation didn't even cross my mind. Worth checking...

The gov. actuator calibration (after checking and correctly re-installing the throttle cable) was the first thing that I did after noticing the problems. Calibration ran OK and was finished without any errors whatsoever. High idle is around 1980-2000 rpm, and under full load (both hyd. pumps loaded, for example pulling the boom up or stick in and holding against the end of the cylinder stroke) it doesn't drop below 1760-1780 rpm, as long as the speed dial is on 10. Which is (almost) OK, but what persists is the smoke issue - and, the fact that at lower positions on the dial, the engine does tend to bog down / drop rpm's too much.

However, concerning the starting issue, maybe I wasn't too clear before (English not being my native language - sorry about that). The engine DOES start at any position on the dial (including 1). It's just that at positions below 3-4, you have to crank it for approx. 5-6, maybe 7 seconds, and only then it starts. If it's above that, it starts almost instantaneously...

Regarding the machine's hours... well, the service meter reads approx. 20500. I know it's old, but it's been running well until last year (I think I've mentioned before, that it's been with the same owner for well over 10 years).

I'll see what happens tomorrow (Monday) and return with feedback...

Thanks again for all suggestions!

 

[MHDim]

Short update (but without big news) - the machine has been working since Monday, I had time to see it only today, since I've been busy with other repairs. I didn't spend much time with it, as I had something else to do at the respective site, but the operator (who is an experienced guy) says that as long as he keeps the engine dial on 9 or 10, it works well, with no obvious lack of power, sounds fine, temperatures OK, no complaints whatsoever. It still blows some smoke... maybe a little less than during my tests, but it could have been just my impression (it was windy today).

Normally I don't like giving up until it's 100% solved, but in this case, I guess for now, I'll stick with the golden rule "if it works, don't mess with it" (since anyway, I have other repairs going on) and see what the future brings...

 

[MHDim]

Another update - I don't mean to be annoying, it's just that I usually like to give written feedback about this kind of weird problems, just in case someone else will (maybe) use the info, tomorrow, next month or 5 years later...

In the meantime, I incidentally found out that the injector nozzles were swapped in June 2017 (not autumn, as I said before), and - more important - they were NOT genuine Cat parts, but cheap aftermarkets. A few days ago I visited the machine to replace a starting motor on it, and, armed with this new info, I tried the first possible empirical test - loosening the injector lines, one by one, while carefully listening. Sure enough, counting from the front (=fan) of the engine...:

No. 1 - minimal RPM drop
No. 2 - no noticeable difference
No. 3 - significant RPM drop, engine starting to sound rough
No. 4 - significant RPM drop, engine starting to sound rough
No. 5 - no noticeable difference
No. 6 - significant RPM drop, engine starting to sound rough

In my mind, it's clear that cylinders 2 & 5 are definitely not working right, and also no. 1 doesn't seem to work 100%. Rather strange, considering that normally, it sounds really nice & "round"... but that's what the test showed. I will repeat, that engine power is (sort of) OK, meaning that at dial position 10, under full load it stays at ~1800 RPM, but at lower dial positions, it does tend to lack power, engine bogging down too much.

The generous amounts of (what seems like) diesel smoke are still present.

Starting is, again, the same - below position 3 (...4) of the dial, you have to crank it for a good 5-6 seconds to start; above that, it starts after less than 1 second of cranking.

I will try to get hold of 2 or 3 good injector nozzles and I'll return with feedback...

 

[heymccall]

The 1800 under "full load" is a misconception. That PCM has engine rpms as it target, and destrokes the pumps accordingly to maintain target RPM. You can watch the NFC for each pump through the monitor to verify the destroking.
It won't fully destroke them, but, as an aside, my 324D machines will 100% destroke the pumps (all hydraulic functions stop) in an effort to maintain target rpms.

 

[MHDim]

Yes, that's correct - by "full load" I meant the maximum load allowed by the electronic control system, with both pumps fully loaded (for ex., pulling boom up or stick in against the end of the cylinders' travel). As far as I know, under those conditions the resultant RPM should be as close as possible to the value given in SIS "Engine Performance Specification" as "Full Load Speed".
Interesting info about the D-series, I haven't worked on pump control issues on anything later than the C generation. Also as an aside, on generations B and C, pump destroking under load (in order to maintain target RPM) is not performed by NFC, but by PSP (power shift pressure) and is common to both pumps - yes, it's shown on the monitor in the service menu, even if it's just a calculated value, as they have no sensor for PS pressure. NFC (which is separate for each pump) is responsible for destroking when there is no demand for oil / control levers in neutral. I repeat that this generally goes for series B and C, it's interesting if they changed the principle starting with D's...

 

[Centexhoe]

Saw similar problems like this on a D346 V8 engine, checked fuel filter, delivery, fuel pressure, changed nozzles, and so on. Didn't really show any extra smoke though. Finally turned out that about 3 of the blades were gone off of the hot side turbine in the turbo. Exchanged turbo and no more problems.