Surge Tank Failures

[DonGee]

Noticed that the radiator surge tank on my 2005 Itasca Horizon W/ 400 Cummins was leaking. Checked with my local dealer and was informed that they had replaced several. Just a note to keep an eye on yours. It was replaced on warranty.

Don

[DonGee]

Noticed that the radiator surge tank on my 2005 Itasca Horizon W/ 400 Cummins was leaking. Checked with my local dealer and was informed that they had replaced several. Just a note to keep an eye on yours. It was replaced on warranty.

Don

[Harry B]

Don, After how many miles of driving did this occur?

I have now heard of several units having this problem. Is it age related or use related?

[John_Canfield]

Freightliner coolant surge tank failures are very common. We just had ours replaced with a clear tank from a Freightliner truck.

Details in this earlier thread.

One good aspect of the cooling system is unlike most automobiles, the cooling system is apparently not under pressure. Freightliner in Tolleson (Phoenix) said I could run with the cap off of the tank all day long and it would make absolutely no difference in the system's cooling ability.

[Cruzer]

I can't believe that. Methinks the FL guy is wrong on that one. A 50/50 coolant mixture in itself will boil at a higher temp than water. But, the FL will run up to 235 degrees before the engine's ECM will derate the unit. Ther's no way you can run at 235 with just a 50/50 mix. By increasing the pressure, you increase the boiling point. A 7 PSI cap adds quite a few degrees to that number while a 14-15 PSI cap adds much more.

I've taken the cap off the surge tank on my '04 Freightliner XC and there was plenty of pressure in there. Then again, maybe that's why they put a pressure cap on the tank.

I think that the FL guy meant you can run all day "at idle, going downhill". That would keep the temp down low enough that you wouldn't need to pressurize the system.

[John_Canfield]

He was quite emphatic about his 'not under pressure' statement. Perhaps he means the surge tank is not under pressure. Could be the cooling system is under some pressure but somehow the surge tank isn't part of that loop.

I'll probe more when we are there next Tuesday and ask a tech as well.

[LK23]

Like many others, my coolant reservoir was replaced by Freightliner at 10,000 miles. I did not see the defective tank to know where it was leaking. I now have 23,000 miles. Where should I look for the defect?

[jimandsue60]

My surge tank has pressure on it. It also has a pressure relief cap on it. I sure wish I had one where I could see the coolant level.

Jim

[John_Canfield]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by LK23:
Like many others, my coolant reservoir was replaced by Freightliner at 10,000 miles. I did not see the defective tank to know where it was leaking. I now have 23,000 miles. Where should I look for the defect? </div></BLOCKQUOTE>Rex - our tank failed at the neck where the metal cap sits. When the service tech removed the metal cap, the neck broke.