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COOLANT ISSUE ON 2002 CHEVY 2500 HD DIESEL

195 Views 9 Replies 3 Participants Last post by  heartcross86
Hey guys, I recently had all new Bosh injectors replaced and she is running like a top. In the last few weeks the coolant light came on, I look in the reservoir and sure enough she needed coolant, added it. Then today it does it again. I don't know if maybe there might be an air bubble for when they took things off....or something else. Oil shows no signs of any coolant in it. Exhaust upon warm up or any other time has no sweet smell. Absolutely not a leak one of anything under this truck. So right now, I am just watching it. Any suggestions or thoughts?? I did have my mechanics take a look and they confirmed everything I said and checked. Pic of hard working truck. P.S. she doesn"t haul this much this often.
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It does take some time to get all the air out after draining the cooling system. I'd keep an eye on it though.
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This is why I also drill a very tiny hole into every thermostat I ever replace. 1/16" or smaller and air can't get trapped. To large and the truck won't get up to operating temp during winter months and it will come across the dic saying can't reach operating temp
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It does take some time to get all the air out after draining the cooling system. I'd keep an eye on it though.
Ohhhh believe me....I am watching it like a hawk. I never want this to overheat or get coolant in the oil. The oil is good and black and newly changed. I have found that even when you change oil on the diesel, the oil is black, always.
It does take some time to get all the air out after draining the cooling system. I'd keep an eye on it though.
Just curious, how many times have you had to replace injectors on your 2002? Mine has about 320.000 miles on it.
Just curious, how many times have you had to replace injectors on your 2002? Mine has about 320.000 miles on it.
2 times under warranty and did it 3 times myself. About every 80k miles. Actually expecting I might have to do another set soon but so far, so good for now.
This is the first time I have had them done...ever. Mechanics couldn't believe it....I faithfully use Hotshots secret...Guess I've been really lucky and blessed! I put Bosh injectors in for replacements. I am the original owner...ty for the info!!
Just curious, how many times have you had to replace injectors on your 2002? Mine has about 320.000 miles on it.
My 02 has had all injectors done 1x at 198k and 1 injector back while under warranty now have 252k on it
Injector failure on LB7s is a result of wear (erosion) from small particles (VERY small) of trash in the fuel. At 20,000+ psi, anything in the fuel becomes a problem and what happens is that the insides of your injectors are actually "sandblasted". This is what GM & Bosch discovered back when these trucks were new and these injectors first started failing. Remember the recall on the fuel filters that GM did around 2004? That was an attempt to solve the problem with filtration. Didn't work because the particles are too small for current filter technology. What did work was redesigning the injectors so that the needle / seat interface is not as susceptible to wear from erosion. How much your injectors are sandblasted depends on how much crap is in your fuel. My personal theory about the vast differences in mileage people get from LB7 injectors is that it is dependent on where you live (where your diesel comes from). As in, which refinery. My brother bought his 2003 new and still has it just like me. He had one set of injectors done at around 150k. But he lived over 1,000 miles away from here for the years leading up to that. Meaning, he never ran the same diesel I did. Otherwise he hasn't done anything different than me. No additives, nothing really different but where our fuel came from. Yet I was on my 3rd set of injectors before he ever had problems with his first set. Nothing else I can think of explains that difference given that it is known that the cause of the problem is trash in the fuel that is too small to filter out.

Anyway, lubrication won't stop erosion from "sandblasting". What saves you from that is little to no trash in the fuel you are running. And that is apparently very dependent on where your fuel is refined.
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Injector failure on LB7s is a result of wear (erosion) from small particles (VERY small) of trash in the fuel. At 20,000+ psi, anything in the fuel becomes a problem and what happens is that the insides of your injectors are actually "sandblasted". This is what GM & Bosch discovered back when these trucks were new and these injectors first started failing. Remember the recall on the fuel filters that GM did around 2004? That was an attempt to solve the problem with filtration. Didn't work because the particles are too small for current filter technology. What did work was redesigning the injectors so that the needle / seat interface is not as susceptible to wear from erosion. How much your injectors are sandblasted depends on how much crap is in your fuel. My personal theory about the vast differences in mileage people get from LB7 injectors is that it is dependent on where you live (where your diesel comes from). As in, which refinery. My brother bought his 2003 new and still has it just like me. He had one set of injectors done at around 150k. But he lived over 1,000 miles away from here for the years leading up to that. Meaning, he never ran the same diesel I did. Otherwise he hasn't done anything different than me. No additives, nothing really different but where our fuel came from. Yet I was on my 3rd set of injectors before he ever had problems with his first set. Nothing else I can think of explains that difference given that it is known that the cause of the problem is trash in the fuel that is too small to filter out.

Anyway, lubrication won't stop erosion from "sandblasting". What saves you from that is little to no trash in the fuel you are running. And that is apparently very dependent on where your fuel is refined.
Ty for sharing!! Very interesting theory that makes sense.
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