Yikes! Headgasket time.....

[Tim]

I was doing some routine stuff on the Sienna today (transmission fluid and rotating the tires).

During my normal scanning around I noticed the coolant overflow was about a half inch below full and looked "dirty".

Popped the cap and looked inside...slight oil film on top and coolant was seriously off color. Last flushed in December.

Did the bubble test at 3,000 rpm and it looked like a jacuzzi!

So, took an oil sample and will mail off to Blackstone Monday morning. Even though I only had 1,750 miles on this drain, I went ahead and changed it to get out the crud I suspect was in there.

We've owned this vehicle since new and it has been babied and over-maintained. Guess you just can't stop some things from happening no matter how careful you are.

Looks like decision time. '98 Sienna with 177,500 miles, but I know it...vs ---- shoot on another vehicle. Daughter starts college next year, so I don't think I want to be spending a bunch of money on a new(er) car now.


Tim

 

[Aldaris]

A blown head gasket may be a foregone conclusion in this case.

 

[Tim]

Quote:

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A blown head gasket may be a foregone conclusion in this case.

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That's where my money is!

 

[MrCritical]

Spend the headgasket money on the difference between your Sienna and another used Sienna.

 

[Cutehumor]

bar's leak

 

[Drew99GT]

Were the bubbles in the overflow, or the radiator itself? If inside the overflow only, could be a bad rad cap.

 

[Tim]

In the overflow....along with the oil.

 

[mechtech2]

Don't forget that a manifold gasket leak on many engines can have the similar symptoms.
The bubbling indicates a head or head gasket, though.

 

[Tim]

Quote:

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Don't forget that a manifold gasket leak on many engines can have the similar symptoms.
The bubbling indicates a head or head gasket, though.

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An intake gasket leak wouldn't be putting oil in the coolant though, would it?

 

[Tim]

Here's an update:

Waiting on a result from Blackstone - they have the sample now.

I went ahead and changed the cap as suggested above by Drew...I figured I didn't have anything to lose. Did another bubble test at 3,000 rpm with a fully hot engine. No bubbles.

However, just running the vehicle 10 miles to get it hot I already noticed a slight film on the previously fresh coolant in the bottle. Could be carryover...

I went ahead and cleaned the overflow out thoroughly and re-filled with fresh again.

Should have the Blackstone result tomorrow. If it comes back clean, I might be inclined to think I just had a bad cap....except for that oily sheen.


Thanks for the replies and tips,


Tim

 

[Master ACiD]

does it have an water to oil, oil cooler?

how about an automatic transmission? my dodge stratus busted a transmission cooler in the radiator and slowly pumped trans oil into the radiator fluid when the engine was running. when i shut it off the radiator fluid crept into the trans.

 

[Tim]

The plot thickens....

Got my Blackstone report tonight - oil is fine. No water, no glycol.

There is no water to oil oil cooler, but the transmission cooler is integrated into the radiator like on so many vehicles. I am going to go over to Siennaclub.org to see if anyone has ever reported a transmission cooler leaks there.

I did just do the transmission fluid this weekend and it came out nice and red and perfect (like usual)...but my eyes are no ICP analyzer!

My next two possible steps are to pull a coolant sample and have it analyzed, or de-grease and citric acid clean my cooling system. I may just have some garf in there from 9 years and 178k miles...even though I have drained, flushed and re-filled several times in the past 75k miles/5 years.


Tim

 

[TooManyWheels]

Tim - Have you done a compression test?

 

[Master ACiD]

tim, go to auto parts store and buy a new radiator cap and a rubber tyre valve. drill a 3/8 (i think thats the size) hole in youre OLD radiator cap and install the yre valve. put the cap on the radiator and pressureize it with air from a compressor. be carefull not to go over 10 or 15lbs and DONt run the engine with this cap as the pressure relief will be removed as part of the hole drilling. with pressure in the radiator, you should be able to see if it holds pressure. if it doesnt, and thats what im betting, see if you can see or HEAR where its leaking too. if all else fails, drop the trans pan and inspect for sludge and coolant on the bottom of the pan.
my vote goes to an internal radiator leak.

as an alternative to this odreal, you can probably send a sample of transmission fluid out to blackstone for analisys.

dont forget to put the new radiuator cap you bought back on when youre done

 

[Chris142]

Quote:

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tim, go to auto parts store and buy a new radiator cap and a rubber tyre valve. drill a 3/8 (i think thats the size) hole in youre OLD radiator cap and install the yre valve. put the cap on the radiator and pressureize it with air from a compressor. be carefull not to go over 10 or 15lbs and DONt run the engine with this cap as the pressure relief will be removed as part of the hole drilling. with pressure in the radiator, you should be able to see if it holds pressure. if it doesnt, and thats what im betting, see if you can see or HEAR where its leaking too. if all else fails, drop the trans pan and inspect for sludge and coolant on the bottom of the pan.
my vote goes to an internal radiator leak.

as an alternative to this odreal, you can probably send a sample of transmission fluid out to blackstone for analisys.

dont forget to put the new radiuator cap you bought back on when youre done

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Wouldn't it be easier to borrow a pressure tester from one of the auto parts stores?

If it was transmission fluid the mix would be pink in the bottle.

 

[Tim]

Quote:

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If it was transmission fluid the mix would be pink in the bottle.

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Well, I'm not so sure about that.

I drained the coolant tonight and now that I have it out in the light...it is a pretty burnt orange. Just what I think you'd expect from mixing Prestone all makes/all color (yellow) and red atf.

I tried mixing a little motor oil in fresh coolant and couldn't get anything approximating what was in my car. But the atf, that was another story.

I only have to decide if I bother with a coolant analysis, or just go out and spend the $210 for a radiator.

Tim

 

[Master ACiD]

check the trans dipstick take note of the fluid "look". if theres enough coolant in the trans youll see a milky white substance on the trans dipstick when its good and hot.

Wouldn't it be easier to borrow a pressure tester from one of the auto parts stores? "
if you can FINd one to rent then sure. but when i had this problem i couldnt find anyone who had a tester to borrow or rent.

 

[Tim]

I've checked the atf on the stick and also drained it out the drain plug (I noted the low overflow while working on the atf).

The atf looked its normal perfect just out of the bottle red. No abnormalities noted.

I would think when hot and pressurized, the coolant would go into the atf. Then on cooling, the atf would get sucked into the rad. I just can't find any evidence of coolant in the atf.

I think maybe I'll disconnect the trans cooler lines and hook up the Mighty-Vac and see if the cooler lines will hold a vac. Unfortunately I probably won't be able to do this until Sunday.

 

[ARB1977]

Get the coolant analyized as well as the atf...either way it would be cheaper than just buying a new radiator.

 

[Master ACiD]

Quote:

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I've checked the atf on the stick and also drained it out the drain plug (I noted the low overflow while working on the atf).

The atf looked its normal perfect just out of the bottle red. No abnormalities noted.

I would think when hot and pressurized, the coolant would go into the atf. Then on cooling, the atf would get sucked into the rad. I just can't find any evidence of coolant in the atf.

I think maybe I'll disconnect the trans cooler lines and hook up the Mighty-Vac and see if the cooler lines will hold a vac. Unfortunately I probably won't be able to do this until Sunday.

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the atf is under hundreds of psi so it overcomes the radiators comparitely weak 12-16psi pressure when the engine is running. if you do have a leak in this area the atf will pump into the radiator while the engine is running. once you thrn the engine off, the atf pressure drops to zero and the radiator still has 12-16psi, so it pumps water into the atf.

this is of course, assuming you really do have an atf leak. let us know what you find out.