coolant recovery tank question

[JimJ1485]

The rudimenrtary understanding of cooling systems I have suggests that the system is under pressure (a closed system) that is controlled in part by the amount of pressure on the cap. I have a cooling issue and have been trying to discover the leak I believe exists. I removed the overflow tank to check for leaks. There is a hole near the top on the back of the tank. Is this supposed to be open or has a cap or something fallen off? Wouldn't this cause low pressure and coolant loss? The hole definitely looks like it belongs there, but it confuses me as to the reason.

[FIREM]

Hole is a vent for the "open air" side of the tank. Our overflow tanks are combo pressure/open reserve tank. Pressure cap and system pressure cause coolant to expand into the space from "hot full" to the cap. IF overfilled or in the event of a mild overtemp coolant would go into the "reserve" section and drawn back in when cooled. That is why that sescion is vented at the hole.

[user97]

Yes, as FIREM said -- the tank is really two tanks in one -- one emergency overflow (which always should be empty), which is non-pressurized, and the much smaller one towards the engine which is pressurized.

The pressurized portion of the tank has two hoses connected to it -- the smaller one on the side close to the top and larger one on the bottom. The coolant always circulates through the pressurized portion of the overflow tank as a part of de-airisation circuit. Hence you may see a slightly different level in the pressurized side of the bottle at the same coolant temperature between running and non-running engine.

Good luck...

[300maximilien]

have you tried or had pressurizing your cooling system done to check for leaks?

[JimJ1485]

That will be my next step.
Thanks

[Arved]

Autozone has a pressure tester you can borrow (pay for/return for refund). I find it invaluable for checking leaks. I might have to find a cheaper one for my toolbox.

[JimJ1485]

anyone have the Mopar part number for the reservoir?

[Arved]

anyone have the Mopar part number for the reservoir?

From my 2000 LH Parts manual:

04758269AB BOTTLE, Pressurized Coolant
04596198 CAP, Radiator

The cap isn't your standard looking radiator cap, but you can use a regular (Stant brand or others) cap. I think the factory cap looks cool, and being plastic, won't be as hot to the touch when it's hot. But with a MSRP of $23.70, it's hard to justify. But if you want your car all-original...

Don't forget to omit the leading zeros when looking up parts online.

1st Chrysler Parts has the AB bottle for $38.94. It's been superceded by an AC part, that they're selling for $62.10. MSRP on the bottle is $54.10 for the AB, and $86.25 for the AC. FWIW, the Balkamp (my box was labeled Dorman Products) at Napa Autoparts was $66.10, but it included a radiator cap. There were problems reported with Dorman bottles, but supposedly, these have been rectified in modern production. I plan on keeping mine until my 1 year warrenty is up, then going with a genuine Mopar. I may buy the Mopar AB now. That price is very, very tempting.

I would be very tempted to stick with the AB at that price.

[mnitetrain]

Pretty sure the pressure cap is included with the MOPAR recovery tank...

[Bill Putney]

...1st Chrysler Parts has the AB bottle for $38.94. It's been superceded by an AC part, that they're selling for $62.10. MSRP on the bottle is $54.10 for the AB, and $86.25 for the AC...I may buy the Mopar AB now. That price is very, very tempting.

I would be very tempted to stick with the AB at that price.

I doubt the ...AB is available.

One of the frustrating things with some of the on-line parts databases now is that they don't always show supercession (they were pretty good about that a couple of years ago), and continue to show parts that are not available anymore. Not sure if that is a marketing trick to get people to place the order to get the older part with its older, lower price, and a large percentage of those, when informed it is not available and then told about the superceding part, will just tell the dealer to go ahead with the newer, more expensive part - essentially a bait and switch - or if the database managers are super lazy or cheap on maintaining the information - perhaps a conscious decision to do both: Bait and switch to increase business for their dealer customers *and* they don't have to have as many people to properly maintain the database - a win-win for them - and dealers using *that* database will have an advantage over dealers that use a better parts-lookup service (unless they loose a lot of customers over it - which they may be banking against). And it may in fact work for them as the number of competing on-line discount dealers out there appears to be dwindling. So if the one you're dealing with is doing the bait and switch database, where else are you going to go.

I suggest you message the dealer with your parts list and ask them for the availability (including estimated delivery time) and supercession before placing the order. I've started doing that most of the time. It will give the dealer incentive to use a better service or complain to the ones they are using so they don't spend all their time answering their customers' questions like that.

...FWIW, the Balkamp (my box was labeled Dorman Products) at Napa Autoparts was $66.10, but it included a radiator cap.

Pretty sure the pressure cap is included with the MOPAR recovery tank...

That is correct.

[JimJ1485]

thanks for the info.

[Arved]

...FWIW, the Balkamp (my box was labeled Dorman Products) at Napa Autoparts was $66.10, but it included a radiator cap.

Pretty sure the pressure cap is included with the MOPAR recovery tank...

That is correct.[/quote]

Just replaced the Balkamp/Dorman water bottle with a MOPAR part. The 3-month old Balkamp/Dorman water bottle split in the back. What a freaking waste of money. Reports that the Dorman water bottle has been revised may be correct, but the revised part is at least as bad as the original.

FWIW, the Mopar bottle at the dealer was about $20 more than the Balkamp/Dorman bottle at Napa Auto Parts. You can probably save more mailorder, but when you need one, you need one. I couldn't afford to be without my daily driver while I waited for a @#$% water bottle. Thankfully, my local 5-star had one on the shelf. Don't cheap out - when Bill advises us to get the Mopar water bottle, he's not kidding.

I probably could have returned the Balkamp/Dorman water bottle under warranty - and gotten another @#$% water bottle that would have split again in 3 months?

FWIW #2: Yes, the Mopar water bottle came with a cap, but it wasn't the original fancy plastic one you see in the parts catalog. It looks to be a heavy duty model - better built than the Made in Israel cap I bought at Autozone, which was not bad at all.

Anyway - the $20 savings is not worth the hassle of being stuck on the side of the road with steam pouring out from under the hood, having to limp ~5 miles home, bumming a ride to the dealer to pick up the tank, another bottle of Zerex G-05 (luckily I had a spare, or that would be another trip out to Napa auto parts), and missing a day of work. Get the MOPAR water bottle!

[Bill Putney]

...FWIW, the Balkamp (my box was labeled Dorman Products) at Napa Autoparts was $66.10, but it included a radiator cap.

Pretty sure the pressure cap is included with the MOPAR recovery tank...

That is correct.[./quote]

Hey! Watch - your quoting! I fixed that:

...FWIW, the Balkamp (my box was labeled Dorman Products) at Napa Autoparts was $66.10, but it included a radiator cap.

Pretty sure the pressure cap is included with the MOPAR recovery tank...

That is correct.

Didn't want someone to think that I had gotten a Dorman reservoir.

[Arved]

Didn't want someone to think that I had gotten a Dorman reservoir.

You know better. Now I do, too.

[mbyte]

The answer to the question with the hole in the tank Answered one of my questions but I have my recovery tank boiling after I park my car. The gauge says normal temp. Some say its the cap. Is a radiator cap the same as the recovery tank cap? I cant find the cap.

James

[FIREM]

Recovery tank cap= Radiator Cap.
Originally supplied cap was 16 PSI
Replacement Mopar cap is now 17PSI
Higher pressure less prone to “after boil”
Coolant mix also a factor. 50/50 mix freezes at -34, boils at 265. Boiling point goes up 2 degrees per 1PSI cap pressure.
Cap is the usual cause, be sure the entire system can hold pressure, AKA no leaks