CAT 252B3 losing power when below freezing

[Boreal]

I have a 2012 CAT 252B3 with 2,100 hours on it and C3.4 engine. Since our temps have dropped below freezing, I've been having intermittent issues with losing power and smoking. It happened this past Monday when I went out to use it for moving snow. It was about 20*F out and it started fine (I use a block heater), idled fine for 15 minutes then even ran at high idle for 15 minutes but at higher RPM and under load it would lose power, sputter, and smoke. I'm not the best at judging smoke color but it wasn't dark black and it wasn't white. It just looked kinda blue grey. I was running straight number 2 in it then since our stations didn't have winter blend last time I filled up. But I did have hot shots secret in it and I added Lucas injector cleaner. After at least 1-1/2 hours of warm-up, it operated just fine, I got the snow clearing done, then went to town to get winter blend.

I now have winter blend in it which is 20% kerosene and I added more hot shots secret. I cleared snow Tuesday and Wednesday with no issues. A normal warmup cycle and she ran just fine. Temps were in the 20s and low 30s. Then today it was 4* this morning. I ran the block heater for 2 hours and it started right up. I let it idle for 15 minutes, then went to high idle for 15 minutes, worked the cylinders to move the hydraulic oil around and everything was fine. I let it run at high idle for another 5 minutes and it started to smoke and sputter again. Within a minute it would clear itself up and run at high idle again but a few minutes later RPM would drop and it would start sputtering again. This cycle went on for 20 minutes and finally it was running as it should. I cleared snow for 10 minutes without issue and then it started sputtering again. It sputtered off and on for 10 minutes and finally died. It had never actually died before. It started back up, smoked, sputtered, had no throttle response and died again. I put a heater on the fuel filter, plugged in the block heater so at least it wouldn't cool down and let it sit for 20 minutes. It then started and ran just fine as I drove it for 5 minutes to get it out of the way and into its parking spot where I left it.

The injector pump was at least 60*F, the block was around 150*, the fuel filter was right around 32*, and each exhaust port was about 180* when it died. I crack the water separator on the filter every day but I never get anything out of it. Some days I'll hear gurgling when I open the valve and some days I don't hear anything but I never get anything to drain. It's a new CAT fuel filter with less than 50 hours on it.

This is my second winter with the machine. Last winter was colder than normal with more snow than normal and I never had these issues. I did have to warm the fuel filter last year when temps were below zero but I don't remember ever losing power and having the sputtering. Any help is greatly appreciated. Some questions at the top of my mind are:

1. Should I run some iso-HEET in the tank and is that safe for the injectors?
2. Shouldn't I at least get diesel out of the water separator when I drain it? Or do these separators somehow keep the diesel from draining?
3. Should I be draining the separator after operating when at temp or before operating? I'm thinking after operating any water would be liquid and drain vs being frozen.
4. Any other suggestions on what I should try?

TIA

 

[Delmer]

1. No, iso heet is alcohol for gas lines freezing up, which isn't an issue anymore since most gas is 10% alcohol.
2. YES, you should get diesel dripping out, that means you can close it, you might have to pump a priming pump, or crank the engine a second to get fuel out of the water separator. Or turn the key on for a second if you have an electric fuel pump. Put a clean pail under it to catch what comes out to see if there's water. Repeat until you get no more water if you do get some water.
3. Shouldn't matter, but ice won't flow, and ice takes a long time to melt.
4. After working for ten minutes, the block should at least 180. The exhaust manifold might cool off quick so that doesn't mean much, but the block will hold heat for a bit. I'd idle it for a minute, then work gently for five minutes, and then hammer down.

You may have other issues besides waxing and gelling or water, like plugged strainer, filter, suction air leak, fuel tank cap vent plugged, etc. that only show themselves in the stress of the cold.

 

[Coaldust]

Good summary, Delmer.

Boreal could leave a quart of that fuel sitting in a jar, outside, overnight and see if it’s gelling. Maybe. Lots of variables. The “winter blend” may not be “winter blend”. It would be nice to rule that out.

 

[Delmer]

Yeah, Minnesota, could have 20% bio in there...

 

[Boreal]

Thanks guys! I'll try leaving some out in a mason jar and see what it looks like. Other than that, I'm at a loss on how to test the potential issues Delmer mentioned since the problem seems intermittent and temp dependent. I did pull the fuel cap today when it happened and that didn't seem to change anything.

It'll be in the single digits here again tomorrow. I'll try running through a warmup and see if she bucks. If it's bogging again, any other diagnostic or fuel system cleaning tips would be a huge help. It's snow season now and I need my cat running

 

[Delmer]

2. YES, you should get diesel dripping out, that means you can close it, you might have to pump a priming pump, or crank the engine a second to get fuel out of the water separator. Or turn the key on for a second if you have an electric fuel pump. Put a clean pail under it to catch what comes out to see if there's water. Repeat until you get no more water if you do get some water.

Do whatever it takes to get diesel to drip out of the water separator, then you'll know if there's a water problem or not.

4. After working for ten minutes, the block should at least 180. The exhaust manifold might cool off quick so that doesn't mean much, but the block will hold heat for a bit. I'd idle it for a minute, then work gently for five minutes, and then hammer down.

Those temps are cool, either the engine isn't working very hard, or the thermostat isn't closing enough. Could try cardboard over 90% of the radiator if you watch the temp gauge. The fuel should warm up faster than that also, I'd think, could be ice holding the 32 temp.

You may have other issues besides waxing and gelling or water, like plugged strainer, filter, suction air leak, fuel tank cap vent plugged, etc. that only show themselves in the stress of the cold.

Basically you're doing most things right, we don't know what's going on, not an easy one, so just some vague suggestions. I would try to run it low on fuel, then fill up with the winter blend to dilute the summer fuel as much as possible. this "hot shot's secret" is it specifically an anti gel anti waxing product? Don't be afraid to run a hair dryer on the fuel filter to be able to run it to use up the old fuel. The cardboard might help a lot there too. Or run a garden hose on the filter, very fast thawing.

 

[Welder Dave]

What's your air filter like? Could it possibly have ingested some snow that thawed and re-froze?

 

[ThreeCW]

Are you running the winter version of Hot Shot's Secret diesel fuel additive (either "EDT + Winter Defense" or "Diesel Winter Anti-Gel"?

It sounds like your problem started when the temperatures dropped when you still had summer diesel in your CAT. The addition of a quality winter diesel fuel additive will give you about 20 deg F (11 C) reduction in Cold Filter Plug Point (CFPP), which is the temperature that wax crystals restrict fuel flow. Around here (Alberta), our summer diesel has a CFPP about 30 deg F (- 1 C), so with a winter diesel fuel additive, the CFPP of summer diesel can be reduced to about 10 deg F (-12 C).

Your winter diesel fuel should have a considerably lower low temperature rating ... for example, the winter diesel in Southern Alberta is rated for -27 deg F (-33 C). The CFPP for winter fuel can be reduced further by using a quality winter diesel fuel additive.

When you switched from Summer Diesel to Winter Diesel, you would have still had some Summer Diesel in your tank, resulting in the the CFPP being somewhere between summer and winter diesel. You might want to get a sample of the actual fuel in the tank to check it for cloud point with a jar test ... you might also want to put a jar of fuel in the freezer to check it at a lower temperature. If the fuel is clear and you can see through it, the wax is still dissolved in the fuel. If it is cloudy at all, that means that the wax has started to come out of solution and is forming wax crystals. When enough wax crystals form, they will plug your fuel filter / fuel lines and eventually cause the engine to starve for fuel and shut down. I suspect this is what is happening in your case.

As Coaldust and Delmer suggest, the jar test should give you a good visual of what is happening. If you want to sacrifice a fuel filter, cutting open a cold and possibly wax plugged filter might give you a pretty good visual on what is happening too.

 

[ThreeCW]

Boreal - Here is a link to some fuel system plugging problems on some CAT skid steers ... just in case your problem does NOT turn out to be a fuel gelling (waxing) issue.

https://www.heavyequipmentforums.com/threads/cat-226-fuel-problem.78929/

If you still have your old fuel filter kicking around from 50 hours ago, you might want to cut it open and see what is inside to assist with your trouble shooting.

 

[Boreal]

ThreeCW thanks for the link. That gives me some more ideas. It seems inspecting and cleaning the pump/filter assembly will be a good idea just for maintenance also.

The diesel I left out last night is not cloudy but does have a clump in it maybe an inch in diameter that looks like snow. It's 3 degrees out right now. I'll see if I can get a clear picture to post of the clump. This sample was from my transfer tank which had 10 gallons of #2 in it when I filed up with 40 gallons of the 80/20 winter. The loader had maybe an 1/8 of a tank of #2 when I filled it from the transfer tank so there would have been some diluting of the 80/20 winter. I thought the Hot Shots would protect me though.

The Hot Shots I used was the winter anti-gel.

The air filter was new 50 hours ago but I'll inspect it today before startup.

The thermostat could be at issue as well. Thanks for the idea Delmer. There's no gauge cluster in the cab but I'll see if I can monitor the hose temp during warmup to see how the thermostat is functioning. I left the cab heater off yesterday to conserve engine heat but turned it on as the windows fogged. That was shortly before it started stalling.

 

[Delmer]

You've got wax. Warm the fuel up, and/or burn it up, and/or see if the cardboard helps. I assume you have a non contact thermometer, can you see the top if the radiator without opening the door? check the temp there, or other painted metal surface on the engine. Hoses are insulated enough that the outside is influenced by the air temp as much as the coolant temp. If it stumbles after running more than five minutes, shut it off and come back in ten minutes, the engine heat might work better without the fan going.

 

[Boreal]

Thanks Delmer!

The sun is out today and we could hit 20 so maybe that will help also. Guess I'll run it this afternoon when ambient is on my side.

I got quite a bit of water from the separator. I have heat tape wrapped around the filter so the filter and head are about 42 degrees now. I had to run the lift pump from the cab about 5 times until I got diesel from the separator. Glad I know that trick now.

I uploaded pics from the overnight sample and pulled the snow looking piece out for a separate pic. I didn't expect the wax to clump like that. I thought it would just gel. Maybe it's an effect from the additives.

It's an IR temp probe. I'll cover the radiator with cardboard and take temps from there. Radiator is mounted above the engine so easy access with the door closed.

Assuming I can run it and get the fuel warmed up today, should I run to town to get kerosene to add or just add more hot shots or is there something else I should do?

Thanks again for all the help!

 

[ThreeCW]

I have been running Stanadyne Performance Diesel fuel additive which is their all season additive which includes wax / crystal modifiers for cloud point reduction. With the Stanadyne, they say you can run up to 2 times treatment concentration.

I don’t suggest mixing different brands of additives , but perhaps your Hot Shot brand may also list an upper concentration limit. Hot Shot also has an emergency treatment winter gel control that you may consider adding … it is not for daily use but for emergency situations such as yours.

 

[ThreeCW]

Just had a look at your photos … you say it looks like snow … that snow is likely ice from water contamination in your fuel. It looks like you may have a water contamination issue rather than a wax issue.

Try melting down that plug and see if it is water or wax. That will help you to determine what you are testing for.

 

[ThreeCW]

Not sure where you are getting your water from. Perhaps you are buying some wet fuel. It might be time to try another fuel vendor.

As a comparison, I have been using a 300 gallon (1200 L) farm diesel fuel tank for the past 20 years. I treat with 1.5 times the additive concentration and only fill the tank every year or two. I have never had to drain water from either the tank filter or the machine filter. Perhaps I am lucky with water but quality fuel in = quality fuel out.

 

[Boreal]

ThreeCW I had the same thought about it maybe being ice crystals. I put it on the woodstove and it was mostly clear with just a hint of offroad dye so guessing it's crystallized water.

I'm sure the water could be from condensation. I don't have a drain on my bulk tank (55 gallon drum). Do I need to get some water finding paste?

I couldn't wait for warmer temps this afternoon. I decided I wanted to see if I could get it going while it was still single digits. I blocked off the radiator with cardboard, it started right up as always, and I crept the RPMs up as much as I could without it loading up then did some light work for 10 minutes, opened her up and started plowing. I figured as long as the heater core was blowing cold, I wasn't gonna overheat. It performed great for 40 minutes. I kept checking the block temp with IR and it hit 230 so I removed the cardboard. Within 5 minutes she started loading up again so I replaced the cardboard and drove back home.

It's sitting in the sun now. I figure I'll let the built up heat radiate while ambient warms up and I'll top it of with kerosene and more hotshots.

But if it's a water issue, is kerosene gonna help or do I just need to keep dumping the separator?

 

[Boreal]

So just went out to try and dump the separator and got nothing out. I ran the lift pump 5 times. No diesel, no water, nothing. The filter was 36 degrees so wouldn't think there'd be ice blocking it -- especially since I was able to dump it before I ran it. I plugged the heat tape in to see if that gets anything to flow...

 

[ThreeCW]

I would try the Hot Shot’s Diesel Winter Rescue if can find some. It will be compatible with your existing treated fuel.

https://www.hotshotsecret.com/diesel-winter-rescue/

You will need to get rid of the water in your fuel. The water is heavier than diesel so it will accumulate in the bottom of your tank. You might want to siphon fuel from the top of your drum into a jerry can. You could then tip the jerry van over and drain off the bottom thru the vent to remove any water.

And keep draining off the fuel separator on your CAT.

 

[Delmer]

I wouldn't consider this an emergency, and I wouldn't use any "emergency" fuel product. I probably wouldn't use more kerosene in a 2012 either. I'd keep trying the same thing until you get rid of the water and old fuel.

How much of the radiator did you cover? leave an inch or two of the end of all the fins exposed and it should keep cool enough. if it gets that hot, then open it a quarter or half, but don't remove the cardboard if you need to run.

 

[ThreeCW]

You will want to pull the drain plug on your 252B fuel tank at some point as well and get rid is as much water from the fuel tank as you can.