Replaced Diacovery coolant tank

[milligsc]

Freightliner chassis with a CAT C7. The old tank was crumbling at the seams so I figured it was time. Took about an hour and a half. Put a new cap on it and ran the engine for 20 min with the cap unsealed. You need to pull the brackets away from the tank when tightening the bolts or it may rub. Attachment 254786

[magaliasram]

Originally Posted by milligsc

Freightliner chassis with a CAT C7. The old tank was crumbling at the seams so I figured it was time. Took about an hour and a half. Put a new cap on it and ran the engine for 20 min with the cap unsealed. You need to pull the brackets away from the tank when tightening the bolts or it may rub. Attachment 254786Attachment 254787Attachment 254788

Was the tank actually leaking at the seam? Or was the replacement simply because the tank was cracked?

[Bahamaniac]

That was the first thing I did when I bought mine.

[milligsc]

Originally Posted by magaliasram

Was the tank actually leaking at the seam? Or was the replacement simply because the tank was cracked?

Wasn't leaking but it was crumbling around the seam. I'd rather replace at home.

[DegoRed]

Originally Posted by milligsc

Wasn't leaking but it was crumbling around the seam. I'd rather replace at home.

You made a good call , ours cracked just a tiny tiny bit at a seam on Hwy 93 between Phoenix & Kingman on that long steep grade, was an absolute mess. Radiator fluid turned everything white, entire back of coach, our Jeep towed behind, etc. Had to JB weld our tank to a slow small drip to keep going and avoid a tow. Ended up having to next day ship a new in from Spartan, next day shipping cost as much as the tank. Changed it out at the RV park, took about 1 hour.

This is one of these maintenance things to do that no one talks about, guess these tanks are prone to breaking, especially when exposed to sun.

[MN_Traveler]

I want to thank the OP for this thread. Ive been periodically noting that my coolant surge tank has become brittle at the central seam. Kept thinking i should do something about it. After reading this thread, took another look, and is starting to show spider cracks on the tank itself. Just brought it in to the shop to get replaced - they say they replace these tanks all the time because thy become brittle. A little PM Goes a long way!

[milligsc]

Originally Posted by MN_Traveler

I want to thank the OP for this thread. Ive been periodically noting that my coolant surge tank has become brittle at the central seam. Kept thinking i should do something about it. After reading this thread, took another look, and is starting to show spider cracks on the tank itself. Just brought it in to the shop to get replaced - they say they replace these tanks all the time because thy become brittle. A little PM Goes a long way!

Always better to fix things at home vs ou on the road.

[Jim_HiTek]

Replaced my surge tank in Jan. '18. Took me far longer then expected but learned a lot. Now that I've done one, I'd say for a Journey diesel Cat, Freightliner XC chassis, I'd allow 3 hours for the work at a leisurly pace. Here's my blog article about it, with pictures and links to resources: Radiator & cooling system

Mine had many spider cracks and after 2 years started weeping a bit so it was obvious that it needed replacing. But didn't cause a breakdown. I used Eternabond tape to delay the inevitable.