Author Topic: Cat 3126, low power, low boost, low fuel consumption  (Read 3732 times)

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Offline gbarney

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Re: Cat 3126, low power, low boost, low fuel consumption
« Reply #25 on: July 25, 2019, 05:32:58 PM »
Rebuilt injectors returned and installed. Rebuilder reported finding "metal chips" in the injectors.

Engine cranks but will not start. Initial check shows there is no oil from the HEUI pump. Not just no, or low, pressure, no oil at all. Engine oil level is in the operating range, engine oil pump builds slight pressure on dash gage while cranking, enough to turn out the low oil pressure light. I pulled the test port plug on the HEUI oil gallery in the head, no oil present in the galley. This was after a total of 15 to 20 minutes cranking time (30 sec. crank / 2 min. cool intervals).

I will try to get a pressure gage on the HEUI output line tomorrow just to verify.

Expect I will be buying another IAPCV, or another HEUI Pump, or both.

Offline David.e.atherton

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Re: Cat 3126, low power, low boost, low fuel consumption
« Reply #26 on: July 27, 2019, 08:21:49 PM »
Hi , what are you doing ? Kinda sorta following your post. Question service repair shop,
Caterpillar dealer or service shop that worked on your engine. What is happening there
is no engine oil being pushed to the Heui pump from oil pump ln oil pan. Possible reason
air locked at oil cooler check valves.column of air in system will not open the check valves
In oil cooler. Next question disconnect hot 12 volt wire going to engine intake heater and
try starting with starting fluid. Engine will light on starting fluid but not stay running. Your
Problem first with no start ( Injection Actuation Pressure Sensor ) disconnect the IAP Sensor
engine should start and run at idle but no power. What that is telling you the IAP Sensor
is bad. If Connect Cat ET you should have a event code 164-4 or 164-7 . No luck than go
next to the Injection Actuation Pressure Regulaor and Cat ET Code or 42-11 Injection
Actuation Pressure Regulator Fault.. what that is telling you the Injection Actuation Pressure
Regulator is not letting the high pressure engine to the injectors. Or the electrical connection
Is not getting to the Solenoid on the regulator. That is where you need to go to make engine
run. Before anything make sure engine oil pump in oil pan the relief valve is not stuck open on oil pump, and second make sure engine oil is bleed at both of the oil cooler check valves.
Ask Dave, Dave Atherton Retired Cat Mechanic

Offline David.e.atherton

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Re: Cat 3126, low power, low boost, low fuel consumption
« Reply #27 on: July 27, 2019, 08:56:29 PM »
gbarney, just add information than may be of help deeper into your problem . You
mention metal chips at injectors screen. It would be my first order of action pull
A oil sample and send out ASAP. Metal floating around in engine oil galleries will
Spell engine failure and it just may be happening right now at engine oil pump in
The oil pan engine oil pump failing and milling of metal first caught up in oil pump relief
Valve is possible for no engine oil to Heui pump. Taking that oil sample will identify
the metal being floating within the engine oil galley. I would also cut open the engine oil filter
To see amount of steel milling present. This information is your first line of defense to
access the extent of travel metal in the oil galley. I do believe I have mentioned oil sampling
before along with others and with out question will pin point what is not working.
Ask Dave, Dave Atherton Retired Cat Mechanic

Offline gbarney

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Re: Cat 3126, low power, low boost, low fuel consumption
« Reply #28 on: July 27, 2019, 11:42:13 PM »
Hi Dave,
Thanks for responding, glad to hear you have been following along.

No shop involved in this project. Just about fed up with paying shops (including Cat shops) $100+/hour to make mistakes. As the song says, "I can make mistakes myself just fine."

Anyway as a recap, other than never making full power this engine was running just fine up until I removed the injectors. Drove it to Arizona last winter, stayed at multiple locations, then back to Seattle this spring. Always starts right up, runs smooth, no stalling or other problems other than lack of power.

Back in 2014, also in Arizona I encountered had encountered severe loss of power, very little boost pressure and what would build took a long time. From a standing start at WOT, maybe half a city block before any boost would register on dash gage. Changing fuel filters didn't help. An independant shop checked it out and said the HEUI pump was failing. HEUI pump was changed, but there was no improvment. Shop swore up and down that pump was bad, that metal was comming out of it. I lost confidence in them, so I took it to the nearest CAT shop, which told me the IAPCV should have been changed before the HEUI pump, since HEUI pumps rarely fail. So they changed the IAPCV, still no improvement. After some more $100+/hr troubleshooting, they decided that the air filter was plugged. After the air filter was replaced, engine performance significantly improved but never back to what it had been prior to this problem.

Now five years and at least 20,000 miles later, it has been in CAT shops multiple times, and been on the dyno, trying to find out why it still doesn't run the way it did before the issues in 2014. Cat shops can't identify a fault or problem, but would be happy to start replacing parts, startng with injectors, just to see if something changes.

So, not having found anything else and reading multiple accounts of HEUI pump failures resulting in metal contamination of injectors, I'm thinking that perhaps the independent shop in 2014 was correct about the HEUI pump failing and perhaps sending metal into the injectors, even though the plugged air filter was the immediate problem. This is why I decided to pull the injectors and send them to a rebuilder. It was the rebuilder that reported finding "metal" inside the injectors. I did not see metal on the outside of the injectors, nor did I see any screens. This is a 1WM series engine, 3126"A", I think it is referred to as. It has the side solenoid injectors, and cross-over tubes that feed HEUI oil to the tops of the injectors. I think screens were on the later model injectors.

I haven't found any trace of metal in the engine oil, on the dip stick, or in the rocker box. After removing the injectors, I removed the rear plug from the HEUI oil gallery in the head and flushed it with brake clean to ensure there weren't any metal filings or chips in it. Again, no metal found.

After reassembly with the rebuilt injectors, it would not start. I removed the test port plug on the HEUI oil gallery and found no oil in the gallery. Cranked engine with the plug removed, still no oil in gallery, so no sense in trying to check HEUI oil pressure since there is no HEUI oil. Unplugged the IAP sensor, so ECM would try to go to default HEUI oil pressure, still did not get any oil in the gallery. Engine oil pressure seems fine, oil light goes out while cranking, and oil pressure gage on dash responds, showing 5 to 10 lb. So the oil pump seems to be picking up oil from sump and pressurizing the lubrication system.

Nothing on the engine has been touched below the rocker box up to this point. No reason for loss of oil to the HEUI pump, or air pockets in oil at the oil cooler check valves, or any other such oil issues. This engine can sit for months and then fire right up without a problem. It only sat for barely two weeks with the injectors out.

I removed the rocker cover and rechecked the cross-over tubes and fittings for leaks. Nothing seen.

Next I checked out the IAPCV. First the coil, resistance was good. Then power to it from the ECM, 4V at Key-On, jumping to 9-10V while cranking. So replaced IAPCV with new unit. While it was removed, cranked engine just to see that oil was actually coming out of the HEUI pump - it was, lots of it. Check the oil for metal, none found. After installing new IAPCV, cranked engine and still no oil to the HEUI oil gallery in the head. So I removed the oil line from the HEUI to the head, drained it and check that it was clear, then reinstalled to the HEUI pump only with the open end pointed down into a drain bucket. Cranked engine, strong stream of oil sprayed into the bucket. Reattached the oil line to the head, still had the oil gallery test port plug removed, and cranked the engine. Oil gallery quickly filled the gallery and flooded out the test port. Great! Finally have oil. Reinstalled the test port plug. Engine cranks, still no start.

Cracked the fitting on fuel pressure regulator at back of head and ran purge pump to check for fuel in head. It has fuel.

I can try to find the oil cooler check valves you mentioned and see if there is oil present there.

It will be Monday before I can get a 5000 psi gage and fittings to check HEUI oil pressure. And maybe some starting fluid.

Any other thoughts or suggestions you may have are welcome.




Offline David.e.atherton

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Re: Cat 3126, low power, low boost, low fuel consumption
« Reply #29 on: July 28, 2019, 05:52:33 AM »
gbarney, well that information would have helped in this problem with your first post. This is now where you need to go. Remove the Injection Actuation Pressure Sensor remove from engine,
Than install a pressure gauge into that IAP open port. With pressure gauge in place crank
engine over and you will need to get pressure reading of 870 psi before engine will start.
After engine start up engine oil pressure at test gauge should go 3,500 to 4,000 psi. There is
no in between readings that mean anything at this point. Note: this is high pressure oil
From Heui pump that test gauge is reading. Going back to first injectors replacement any time
injector or injectors been removed you have to bleed air from check valves at engine oil cooler.
Back at test pressure gauge and correct 870 psi reading of which engine should start look
at your exhaust discharge and you should start seeing white smoke exiting exhaust . Again
If you have followed my first post disconnect 12 volt power from intake heater and while turning
Engine over give little shot of starting fluid and engine should start and idle. If engine will
Only run on starting fluid go back and read first post again. Do you have any diesel fluid
returning back to fuel tank in front if answer is no remove hose on the return fuel pressure
Regulator and turn over engine like you want it to start. Basic from what your now telling
me your system is air locked engine oil and diesel fuel.
Ask Dave, Dave Atherton Retired Cat Mechanic

Offline David.e.atherton

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Re: Cat 3126, low power, low boost, low fuel consumption
« Reply #30 on: July 28, 2019, 06:19:52 AM »
gbarney, I can understand that you want to get your Diesel engine running but you
need to understand without correct technical information and training you can go just so far.
Normally I will not suggest use of starting fluid to untrained Mechanic. In your case and make no mistake about it if you do not remove the 12 volt power wire to the engine intake heater
Your problem will get very big in just a few seconds. The reason for giving engine a little
shot of starting fluid it will spin engine and exhaust all air where starter will crank slower .
and if engine will run only on starting fluid assist that means replacement of the IAP Sensor
Or the IAPR valve.  Troubleshooting your problem would be located in these to parts. Last
With valve cover off and looking at each injector while cranking engine over look for air oil
Bubbles at injector base of each injector for oil leakage you may have o-ring twisted or cut.
This is about all I can assist you with. If you had Cat ET connect at this point you would see the event code I posted on my first post. Ask Dave, Dave Atherton Retired Cat mechanic

Offline gbarney

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Re: Cat 3126, low power, low boost, low fuel consumption
« Reply #31 on: July 28, 2019, 10:39:39 AM »
Hi Dave,
Thanks so much for the info on bleeding air from the filter check valves. Air lock related to having the injectors removed makes much more sense than a random failure of either the HEUI pump or IAPCV during the time injectors are removed.

Took a look at the oil filter housing. I see one plug on the housing just above the oil filter, and another on the top of the housing, near the block, and a few inches toward the front (fan end) of the engine from the oil filter. Are these the two ports for the check valves? To get air out can I remove the plug, and presumable a spring and steel ball, then crank the engine until air is exhausted and oil exits the open port, then reinstall check valve, spring, and plug? If so, should one be done before the other, or both at once?


If I still need to try starting fluid, I will definitly remove power from the manifold heater first.

Offline gbarney

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Re: Cat 3126, low power, low boost, low fuel consumption
« Reply #32 on: July 28, 2019, 09:55:41 PM »
Hi Dave,
Sending an update from today.
1. Engine started using the starting fluid, ran for a minute or so until the starting fluid can was empty. Would not restart afterward.
2. Removed upper cap on oil cooler check valve, cranked engine until oil flooded out. Only took a few seconds. Reassembled popet, spring and cap.
3. Loosend cap on oil cooler check valve near the oil fliter, cranked until oil was leaking from the threads, then re-tightened cap.
4. Tried again to start engine, no start.
5. Opened oil inlet pipe connection at HEUI pump and cranked engine. Oil flooded out. Reassembled connection.
6. Opened test port on HEUI oil gallery in head. Cranked engine. Oil flooded out. Reinstalled test port plug.
7. Cranked engine, no start.
8. Disconnected three wire plug for IAP sensor.
9. Cranked engine, no start.

Tomorrow is Monday, I should be able to rundown a 5,000 PSI gage and connection hardware to test HEUI oil pressure.



Offline David.e.atherton

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Re: Cat 3126, low power, low boost, low fuel consumption
« Reply #33 on: July 29, 2019, 04:11:24 AM »
gbarney, what you just tried and engine will not run is the Injection Actuation Pressure Regulator
Is not opening. The engine will not run until high pressure Heui pump oil operates the injectors.
The use of the starting fluid just reniforced that because engine will not stay running on its own.
Next question are your sure you have power 12 volt going to your ECM that would be pin 40
red wire that is a on/ off key switch . Do not assume anything at this point, the information
I been providing there should be Power to ECM and working within Engine itself. Anyway
You will need power to ECM.than power to IAPR Regulator than 870 psi oil pressure and
engine should run if everything you preformed is correct. Do not use anymore starting fluid
Understanding that you used a complete can that not what I said just a little starting fluid.
 
Ask Dave, Dave Atherton Retired Cat Mechanic

Offline gbarney

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Re: Cat 3126, low power, low boost, low fuel consumption
« Reply #34 on: July 29, 2019, 08:57:47 AM »
Dave,

Thanks again for staying with me on this. Its extremely frustrating and I'm tearing out what little hair I have left.

I have power to the ECM, check engine light comes on for 5 seconds at Key On. I get flash code 5-5 when checked as long as I don't have something unplugged.

I checked power at the 2 wire connector for the IAPCV. I got about 4 volts at Key On, and it jumped up to 9-10 volts while cranking.

After this check, I also thought IAPCV must be bad, bought a new one and installed it. Still didn't start or change anything.

I've also cranked engine with valve cover off looking for possible oil leaks at cross over tubes and injectors. Didn't see any leaks. Seems like there is oil flow HEUI Pump as long as it doesn't have to build up any pressure. This would indicate a bad HEUI Pump, but I want to see it on a gage before spending $1400 on another rebuilt pump. Doesn't make any sense either that a HEUI pump would just go for working fine to failed while sitting for two weeks while the injectors were out.

Offline David.e.atherton

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Re: Cat 3126, low power, low boost, low fuel consumption
« Reply #35 on: July 29, 2019, 05:59:42 PM »
gbarney, guess when you install test gauge into system you will know cranking if engine will start. One question, your injectors Cat new , Cat reman or aftermarket ingectors. No high
pressure engine oil to injectors to start , Injection Actuation Pressure Sensor possible bad,
Injection Actuation Pressure Regulator has voltage at solenoid but undetermined if the valve
Is opening or stuck because engine will not start if no high pressure engine oil. Return fuel check valve air in system. Note: there has been many HEUI pumps changed out because
Low engine oil pressure or no oil pressure. Do not assume that you replaced Injection Actuation Pressure Regulator that that cannot be the no start problem. Without a oil sample you are just
Guessing anything is possible. Point to remember again if you cannot get high pressure
engine oil to the injectors via. IAP Regulator your engine will not start and run. The starting
fluid told you that will run on starting fluid. Take you right back. to the sensor and regulator
Ask Dave, Dave Atherton Retired Cat Mechanic

Offline gbarney

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Re: Cat 3126, low power, low boost, low fuel consumption
« Reply #36 on: July 30, 2019, 05:14:51 PM »
Hi Dave,
I got the pressure gages (5k and 100 psi) got them hooked up and found my problem. With the 5K gage hooked to the HEUI gallery in the head, it showed no pressure with IAP and IAPCV electrical connections hooked up, or with the IAP disconnected, or with 12v jumped directly to the IAPCV. I did the same checks with the 100psi gage and was reading about 100psi.

I then dead-headed the HEUI outlet line directly to the 5Kpsi gage, expecting the same readings. However I got 4,500psi. So great, the HEUI pump is good and the cause of the low pressure is isolated to an oil leak somewhere in the rocker box.

I removed the rocker box cover for about the 4th or 5th time now to check again for oil leaks. This time I reinstalled the intake cross-over tubes so as to be less concerned about cranking the engine with the intake system open. With the intake system closed, I cranked the engine long enough to find the oil leak. There was a flow of oil from under the head of one of the injectors, from its oil exit port.

I called the injector rebuilder and discribed the problem, and they immediately said they were sending me another injector. It should be here tomorrow or Thursday. I'll let you know how it goes when I get it back together.

This is an independent rebuild shop, R S Diesel Injector Service in Bellflower CA. I was looking for a shop that would rebuild my injectors rather than exchange for injectors with unknown histoy that could have other problems, and that is what this shop does. They have good customer reviews. Looks like I'll still end up with one injector that wasn't orginal to this engine. However after looking at my injector serial numbers, it looks to me like one must have already been replaced anyway. Maybe it really doesn't make any difference. The good part is that the shop reponded quickly to rectify the problem.

Offline David.e.atherton

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Re: Cat 3126, low power, low boost, low fuel consumption
« Reply #37 on: July 31, 2019, 02:52:59 PM »
gbarney, yes look at my post above asking about the injectors installed. Many things happen
In troubleshooting and assume that just because I installed this part I will move on and keep
taking parts off. Now that you feel that pin point to faulty injector from rebuild shop this is not
good. Someone was sleeping and injector set now I would question . Reason yes rebuild
Injector if it passed final test before you picked it up and now problem with injector failed and
no start ( think I would pull every injector and recheck at your rebuilder to retest and be
sure your injectors are all to cat spec’s ). Next route I would take and I can tell you are not a
Caterpillar fan but connect Cat ET to your engine and cut out and verify correct injectorl pressure
With engine running. Remember is value of fuel is correct with injector firing you are digging
A very deep hole leading to engine failure. I can only provide advice but that is your choice
as direction taken. Ask Dave, Dave Atherton Retired Cat Mechanic

Offline gbarney

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Re: Cat 3126, low power, low boost, low fuel consumption
« Reply #38 on: August 06, 2019, 08:28:18 AM »
Hi Dave,
Couple of days late but the replacement injector arrived yesterday afternoon. Seems USPS lost track of the shipment for a couple of days.  Anyway, installed the replacement injector. It appears to be a CAT Reman. Engine started after cranking about 15 seconds, and settled down to a smooth idle after another 5 seconds. Ran about 15 minutes, reached operating temperature, increased RPM up to 2000 momentarily a few times, all sounds good. Restarts easily.

Unfortunately I will be away until mid October and will not have time for a test drive before leaving, so I will not know until October if changing the injectors solved the original problem I was having.

I do agree that having one of the rebuilt injectors fail is disconcerting, and raises suspicion about the other five. On the other hand, infant mortatity is always an issue with both new and rebuilt parts. But pulling them all out for retesting now could possibly induce another failure that wouldn't have occurred other wise. In this case, looking back to when I initially tried to start the engine it did try to start briefly on the third thirty-second cranking interval. Then it died and never fired again. So at that point it had to have had HUEI oil pressure and everything else working including all six injectors. The failed injector must have failed at that time, so it likely did passed the rebuilders inspection/test before it was shipped. So this adds another concern and that is that another injector failure of this type would not just disable that cylinder, but be a single point of failure that shuts down the engine. Could occur anywhere, anytime, with any new or rebuilt injector, just a function of the engine design.

You suggested having a cylinder cut-out test done to verify cylinder contribution. Would this test at idle be suficent, or would you also suggest doing at power. Doing it at power is a little more complicated.

I also wanted to pass on to you that I was able to locate and install new injector plug packings. Previously I had installed some O-rings in place of missing or leaking packings at your suggestion. I have the early plastic plugs with the plastic tabs that break off. Two of my plugs had broken tabs so were held in place with zip-ties. The plug repair kits are available at www.densoautoac.com, enter the item number Y1C1CATHUEIC7C9 in the search bar. Each plug comes with a new packing. At $1.10 each, they are cheap enough that you can just use the packing and throw the plug away. The packing looks like it should also fit the later style plugs, as well as the IAPCV plug, and perhaps a few others. The site accepts Paypal and my order arrived in less than a week. They ship from China by DHL, so shipping a bit pricy, about $26.00 for the package.

You commented that I'm not a Caterpillar fan in your last post. I just wanted to mention that I didn't start out that way. I only got that way after several disapointing and frustrating interactions with Caterpillar Service Departments.

Offline David.e.atherton

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Re: Cat 3126, low power, low boost, low fuel consumption
« Reply #39 on: August 07, 2019, 06:57:08 AM »
gbarney, yes I understand you have lost faith in actions of some service shops and have
gone different direction other than Caterpillar. One thing is missing with all of this the OEM
caterpillar parts are the main player here and there are not involved in your option with
Service of Dealerships, the parts just sit on shelf waiting to be bought by someone with a
Caterpillar engine. Long story short, yes Engine is running and you proved a point you can do with out OEM caterpillar parts and gone open market or aftermarket like kind parts and rebuilding injectors from non- caterpillar shop. Yes failure of injector caused a no start and
big question am I going to gave problems ahead with the other Five injectors. That is your
call, I’m a Caterpillar person and giving direction other than Caterpillar spec’s I do not get
Involved and that failed injector throws up a good example as to why I cannot agree this kind
of repair. Your replacement injector ( Cat Reman ) now Engine runs. Wish you the best ahead.
Ask Dave, Dave Atherton Retired Cat Mechanic

Offline gbarney

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Re: Cat 3126, low power, low boost, low fuel consumption
« Reply #40 on: August 07, 2019, 05:02:50 PM »
Hi Dave,
Yes the engine is up and running, thanks to you and your expert guidance and assistance. I cannot thank you enough for the help you have given me on this project and previously as well.

And please don't get me wrong about CAT parts. I always buy the CAT filters, I've replaced a couple of sensors with new CAT parts, and the IAPCV I replaced during this project was a new CAT part. As for these injectors, if I actually knew for certain that I had bad injectors I would likely have replaced them with new CAT units, or possibly CAT rebuilt units. But I didn't know, and neither did the local CAT service shop even after two days on their Dyno. They recommended replacing the injectors "just to see if anything changed," or "just to make sure there isn't a problem with them." New injectors plus labor to install was going to be about $6000.00. To me, that just seemed like a lot of money to spend without any certainty that it would improve anything, or "just to make sure" the injectors aren't the problem. Maybe I'm just cheap.

Having this outside shop rebuild the injectors cost $100 each. So for $600 I found out there was metal shavings in them, and will find out after a test drive if there is any change in engine performance. It is unfortunate that one failed, but it was a known failure mode. If these injectors don't change or improve the low power issue then what ever the probem is, it is something else. If there is an improvement, or even just a change, then there was an injector problem and if I still need to do anything further with injectors I will feel better about spending the money for either new or reman CAT units. And now that you helped me through replacing these injectors, and it turns out it isn't much more complicated that changing a set of spark plugs, I don't have any reason to pay a CAT shop to do it.

Again, I can't thank you enough for all your assistance. I truly appreciate it and could not have done this without it.

Glenn


Offline gbarney

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Re: Cat 3126, low power, low boost, low fuel consumption
« Reply #41 on: October 05, 2019, 09:58:29 AM »
Hi Dave,
I've been away for the past couple of months, I had to leave before I was able to make a test drive on the rig after installing the rebuilt injectors. Now that I am back and was able to do a test drive, I wanted to post a follow up. Pretty simple, engine ran fine, no codes or other issues, but also no improvement in performance. Maximum boost pressure still only 23 psi. Quite disappointing. After the rebuilder reported finding metal particles in the injectors, I had expected better results.

I know you've previously stated that 23 psi maximum boost pressue is normal for this engine, but somehow we are getting different data. The CAT 3126 help line folks have looked up the original test stand data for my serial number, and told me it made 56.4 inches of mercuery boost pressure on the test stand. 56.4 inches of mercury converts to 27.7 psi., and this corresponds with what I recall seeing on the boost pressure gage when I first bought this rig, back when it had much more power for climbing hills.

At this point, I think I've checked or replaced nearly everything on this engine except the turbo-charger itself. Not sure if its is worth trying to replace that or not. The turbine seems to spin freely, and the waste gate moves freely when the actuator rod is disconnected.

Anyway, I wanted to let you know the final result and thank you once again for all your assistance.

Glenn

Offline David.e.atherton

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Re: Cat 3126, low power, low boost, low fuel consumption
« Reply #42 on: October 05, 2019, 11:57:33 PM »
Glen, boost pressure understanding correct information, whoever you feel you want go with
My opinion is clear and stand by information that I posted . Ask a Dave, Dave Atherton
Retired Cat mechanic

Offline gbarney

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Re: Cat 3126, low power, low boost, low fuel consumption
« Reply #43 on: October 10, 2019, 10:07:30 AM »
Thanks again Dave for all you assistance. I accept that your information on performance is accurate. I've often found that equipment performance information based on actual field experience is more reliable than a manufacturers "claimed" performance. Your information is also in line with what I was told by the CAT techs when they had the rig on the Dyno, 23psi boost and 250hp measured at the axle is about normal for this engine.

I frequently run this rig through the mountain passes on I-5 in southern Oregan and northern CA. I still have no explanation for why it used to climb those grades in 5th at better than 50mph, and no longer can come close to that. Maybe the turbo waste gate was frozen shut and it was getting over boosted. Maybe prior to my owning it, someone had hacked into the ECM software and modified the operating perameters to increase performance, something that was subsequently overwritten when the ECM was flashed to update the software. My expectation that the prior performance was "normal" seem to have been unrealistic. Unfortunately I've spent way too much time, effort, and money, trying to get better than 37mph in 3rd when climbing these same grades now. It seems that was the best best performance this rig was ever intended to deliver.

In hindsight, I should have traded this rig for something with better performance several years ago when I first realized the perforance had declined. I think I will start that process now rather than wasting any more effort on this one. Seems that nearly any make/model rig I might buy could easily out perform this one - I see them as they pass me, many at a pretty good clip.

Glenn