Dirt_Floor_Poor Posted October 23, 2022 Share Posted October 23, 2022 I have a 1994 Freightliner FLD120 that has an N14 in it. Today it started blasting, and I mean blasting, antifreeze out of the radiator overflow tube. I didn’t know what to think, but I figured major engine problems. Just to be sure I unhooked the truck air brake compressor output line and the problem stopped. I then hooked it back up and as soon as the air gauge hits 60 psi, it started doing it again. Is there anything I am overlooking in assuming it is a failed compressor? I called and no one close has it. Looks like the soonest I can probably get it is Tuesday. Quote Link to comment Share on other sites More sharing options...
mikem Posted October 23, 2022 Share Posted October 23, 2022 Water cooled air compressor, with a BAD head gasket maybe? Just a guess. Good luck Mike Quote Link to comment Share on other sites More sharing options...
Dirt_Floor_Poor Posted October 23, 2022 Author Share Posted October 23, 2022 33 minutes ago, mikem said: Water cooled air compressor, with a BAD head gasket maybe? Just a guess. Good luck Mike Yes it is a water cooled Holset compressor. Has anyone ever replaced just a gasket and had it hold? I don’t know if I can get those parts or not either. It is the original compressor on the truck. Quote Link to comment Share on other sites More sharing options...
bitty Posted October 23, 2022 Share Posted October 23, 2022 We have a 237 Mack we got in a parts truck in our one dump. It would immediately bubble out of the radiator and swapping the air compressor fixed it.. not sure what exactly you can do to get going again Quote Link to comment Share on other sites More sharing options...
Dirt_Floor_Poor Posted October 23, 2022 Author Share Posted October 23, 2022 12 minutes ago, bitty said: We have a 237 Mack we got in a parts truck in our one dump. It would immediately bubble out of the radiator and swapping the air compressor fixed it.. not sure what exactly you can do to get going again It doesn’t really matter. I would fix it tomorrow if I could find parts locally, but it’s not a big deal if I can’t. We are close enough to home we are just dumping in the bins with the grain carts. There are calling for rain here tomorrow night and Monday. It has only rained one time, a small amount since we started harvest. Quote Link to comment Share on other sites More sharing options...
dale560 Posted October 23, 2022 Share Posted October 23, 2022 31 minutes ago, Dirt_Floor_Poor said: Yes it is a water cooled Holset compressor. Has anyone ever replaced just a gasket and had it hold? I don’t know if I can get those parts or not either. It is the original compressor on the truck. You can get a rebuilt compressor or just a gasket. There are no rod bearings, just a aluminum sized rod. So a lot of times it is shot also so in long run rebuilt compressor is easiest and best. I have seen the coupling spline turn on shaft also so make sure you order spline with compressor. Guys will heat spline to get it off only to have it fail later. 1 1 Quote Link to comment Share on other sites More sharing options...
MinnesotaFarmall Posted October 23, 2022 Share Posted October 23, 2022 If you change the air compressor, I believe the compressor drive gear is part of the engine timing. You HAVE to put the gear back exactly as it was in the timing. 1 Quote Link to comment Share on other sites More sharing options...
dale560 Posted October 23, 2022 Share Posted October 23, 2022 here Are pics of the wrench you will need. The single cyl compressor is for the newer engines and double cyl was on the old 855. I have replaced double compressors where one rod has been broken and wedged into side for a while. If you pull just compressor and fuel pump you don’t need to time it. If you pull pulley and accessories drive you need to time gear. A quick way to is turn engine to tdc mark. Pull pulley and mark where key way is. Put key back in same spot reassembling. The mark for tdc should match again also. That timing is just for the valve set though. Quote Link to comment Share on other sites More sharing options...
Little Red Posted October 23, 2022 Share Posted October 23, 2022 7 minutes ago, MinnesotaFarmall said: If you change the air compressor, I believe the compressor drive gear is part of the engine timing. You HAVE to put the gear back exactly as it was in the timing. That’s only if you pull the accessory drive off, the compressor is bolted on the back of the accessory drive, no timing to worry about 1 Quote Link to comment Share on other sites More sharing options...
Only RED in the shed Posted October 23, 2022 Share Posted October 23, 2022 When you pull fuel pump be sure to check the drive coupler splines for wear on the pump.might need a pump too or if you have a injection shop close they should be able to change shaft Quote Link to comment Share on other sites More sharing options...
dale560 Posted October 23, 2022 Share Posted October 23, 2022 Way back when we didn’t get rebuilt drives we rebushed them and replaced shaft. Here are some pics out of manual if you do pull drive Quote Link to comment Share on other sites More sharing options...
Dirt_Floor_Poor Posted October 23, 2022 Author Share Posted October 23, 2022 Well, no luck on just a gasket today. Looks like the truck isn’t going anywhere for a few days at best. Quote Link to comment Share on other sites More sharing options...
Dirt_Floor_Poor Posted October 25, 2022 Author Share Posted October 25, 2022 I had a bit of luck today as I found out there is a Haldex warehouse close to the Kansas City International Airport today. It is only 25 miles from me. They allow customer pick up, so my dealer called it in and I went and picked it up a few hours later. The compressor was on back order from Cummins, and no one had one. 1 Quote Link to comment Share on other sites More sharing options...
Dirt_Floor_Poor Posted October 26, 2022 Author Share Posted October 26, 2022 I was able to get a hold of the two special Cummins wrenches today. Hopefully they help make this go smooth. 1 Quote Link to comment Share on other sites More sharing options...
Paystar5000 Posted October 26, 2022 Share Posted October 26, 2022 1 hour ago, Dirt_Floor_Poor said: I was able to get a hold of the two special Cummins wrenches today. Hopefully they help make this go smooth. Keep us posted on how that ratchet wrench works. I have a snap on one and one I made out of a craftsman 5/8 wrench. They must be few degrees off each other because if you can’t turn the bolt enough to get the next bite the other one will usually get it for you. Hope your repair goes smoothly. 2 Quote Link to comment Share on other sites More sharing options...
Art From Coleman Posted October 26, 2022 Share Posted October 26, 2022 MAC had/has one called a Micro-Turn, where the 12 pt, 30 degree ends are clocked 15 degree from each other, allowing you to get at the nuts/bolts hidden behind the Cummins PT pump. 1 Quote Link to comment Share on other sites More sharing options...
dale560 Posted October 27, 2022 Share Posted October 27, 2022 57 minutes ago, Art From Coleman said: MAC had/has one called a Micro-Turn, where the 12 pt, 30 degree ends are clocked 15 degree from each other, allowing you to get at the nuts/bolts hidden behind the Cummins PT pump. Never knew that. Quote Link to comment Share on other sites More sharing options...
Dirt_Floor_Poor Posted October 30, 2022 Author Share Posted October 30, 2022 I had my wife run my combine today, so I had a chance to work on this truck. @Paystar5000, that ratchet wrench worked really good. Here’s what it looked like when I started- It went pretty smooth getting it torn down with the special tools- This truck is sitting in a field right now. I got it back together, but it was dark. So no pictures of it completed. I’ll fire it up tomorrow in the light. 1 1 Quote Link to comment Share on other sites More sharing options...
Dirt_Floor_Poor Posted October 30, 2022 Author Share Posted October 30, 2022 Well the repair of this truck was not a success so far. It is still doing the same thing. We are at a loss for the moment. Quote Link to comment Share on other sites More sharing options...
Paystar5000 Posted October 30, 2022 Share Posted October 30, 2022 9 minutes ago, Dirt_Floor_Poor said: Well the repair of this truck was not a success so far. It is still doing the same thing. We are at a loss for the moment. I read your original post more carefully. I’m not sure if my though here is valid or not but I will share it. I am thinking maybe there is an air actuated coolant valve some where? Take off your discharge line from the compressor, cap it and air the truck up. That may tell you if it is coming from somewhere else. I could be way off base here but it seems unlikely the new compressor has a bad head gasket but I would not rule that out either. Quote Link to comment Share on other sites More sharing options...
Only RED in the shed Posted October 31, 2022 Share Posted October 31, 2022 Get a compression test.Napa has them,if fluid turns green you have head gasket or maybe inj. cup. If air comp. didn't change anything. Quote Link to comment Share on other sites More sharing options...
dale560 Posted October 31, 2022 Share Posted October 31, 2022 Yes more than likely a blown gasket or other problem. Inj cups usually put fuel in the radiator just because of pressure difference. I was going to say water pump belt but yours is still in place on the pic. L10 m11 have impeller loosening causing overheat but not big engines they use different setup. Good luck with it. The thermostats are on other side of engine but they either heat or don’t Quote Link to comment Share on other sites More sharing options...
dale560 Posted October 31, 2022 Share Posted October 31, 2022 In all years of changing stuff I have never seen a compressor blown gasket. Either no pump , slow pump or broken. Never one like you describe. Not saying it can’t happen because it is discussed on all repair procedures , but I have never seen one. Seen every other part of air system in disaster but not a head gasket on compressor. Quote Link to comment Share on other sites More sharing options...
Dirt_Floor_Poor Posted October 31, 2022 Author Share Posted October 31, 2022 We had pressurized the truck side and the compressor side like @Paystar5000 suggested, but it would only force coolant out when it was running. If no pressure, it would not do it. We finally were able to narrow it down to a problem on the truck side, not the compressor. The heater valve is on a cable, so we could not figure out where air and water could mix. But… the truck has a sleeper. The bunk heater has an air actuated shut off. I turned the knob to cycle the valve and then it quit doing it. I am going to cap it off for now. It seems to be working properly now. I was sure there was no air actuated shut offs on it. 2 Quote Link to comment Share on other sites More sharing options...
Only RED in the shed Posted October 31, 2022 Share Posted October 31, 2022 If your liners dropped down below .003 they will blow head gasket. Changed lots of them,but you are getting in a rebuild now Quote Link to comment Share on other sites More sharing options...
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