Surge Tank

[ted tcb]

Not knowing the maintenance historyof my car, I'm going to get the coolant changed next week, along with the tablets.

When I look into the surge tank, I see a caramel colour sludge on the side of the fill neck. Could this be an indicator of bars tablets used previously, or is it something ominous? I don't seem to have any leaks, codes, or coolant loss.

Basically, just wondering if this light brown sludge is normal.

Thanks,

Ted.

[adallak]

Not knowing the maintenance historyof my car, I'm going to get the coolant changed next week, along with the tablets.

When I look into the surge tank, I see a caramel colour sludge on the side of the fill neck. Could this be an indicator of bars tablets used previously, or is it something ominous? I don't seem to have any leaks, codes, or coolant loss.

Basically, just wondering if this light brown sludge is normal.

Thanks,

Ted.

Brown sludge is good! One should be concerned if one does not see it...

[Ranger]

That is just sealant you are seeing. It's normal.

[ted tcb]

Excellent! Thanks for the peace of mind, nice to know the previous owner was smart enough to use the pellets.

After a while, you get the impression that only the people on the web forums are savvy enough to add the sealant.

[JohnnyG]

On the other hand, it may never have been changed. I saw the same type of "sludge" in my '99 when I first bought it. It bothered me of course. After about a year or less of ownership, in 2004, I changed all the coolant, replacing with Dexcool and some Bar's Leak Gold powder. I prob. didn't put as much sealant powder in as recommended, about a tube and a half, in the lower rad hose. Filled system with 50/50 mix of Texaco Dexcool and distilled water. The sludge has never returned.

This is a Dexcool car, right?

You are not going to have it flushed, right? (hint: NO)

I removed the surge tank and scrubbed the crap out of it inside, some staining never did come off, but it's been fine so far.

[Ranger]

You know Johnny, now that you mention it, mine is clean as a whistle as well. I suspect some one put the sealant in the surge tank at some point.

[JohnnyG]

Ranger, I did leave out one part. I had already been a member of this board before I bought my car, which is why I checked the tank to begin with. After finding the goop in there, I asked the dealership about it.....they said it was normal and that a lot of these cars are like that. So I can't really say that the sludge is any indication of sealant being put into the surge tank. All I do know for sure is that it has never returned on mine after the change, and that's been just over a year.

[adallak]

Ranger, I did leave out one part. I had already been a member of this board before I bought my car, which is why I checked the tank to begin with. After finding the goop in there, I asked the dealership about it.....they said it was normal and that a lot of these cars are like that. So I can't really say that the sludge is any indication of sealant being put into the surge tank. All I do know for sure is that it has never returned on mine after the change, and that's been just over a year.

that's interesting. I was sure it was caused by supplement...

[Ranger]

Well, FWIW my wifes Bonneville has a conventional radiator cap and overflow tank. The cap on that car has "goop" on the cap as the tabs are put in the radiator. On the other hand, my Cadiilac cap is perfectly clean. I am sure the difference is that the coolant never comes in contact with my cap and does on the bonneville.

[JimD]

For me, evidence of coolant supplement precipitation in the coolant reservoir is a good thing to see. If nothing else, that would indicate there is 'at least enough' supplement in the system to provide the intended protection.

My '98 was factory-fill treated with the supplement and the evidence was apparent in the reservoir within a few thousand miles.

My '04 was not factory-fill treated with the supplement; but I added the supplement on the advice of Guru (thank you, wherever you are). Sure enough, there is precipitated supplement in the reservoir 3,000 miles later.

I do not know how much supplement is too much, but two tubes of the powder is not too much.

[JohnnyG]

Also, keep in mind that on my '99 it did not accumulate on the inside of the cap, but on the little cross bar that you can see when you remove the cap from the surge tank and look inside. It also had coated the inside surface of the tank, complete with all the baffels, which made some of it impossible to remove. Apparently, only where the coolant had been in contact with the surfaces, in the "minimal flow area".

[ted tcb]

Also, keep in mind that on my '99 it did not accumulate on the inside of the cap, but on the little cross bar that you can see when you remove the cap from the surge tank and look inside. It also had coated the inside surface of the tank, complete with all the baffels, which made some of it impossible to remove. Apparently, only where the coolant had been in contact with the surfaces, in the "minimal flow area".

My accumulation isn't on the cap, but on the side of the fill neck ... it certainly looks like the byproduct of ginger root.