Jump to content
CaddyInfo Cadillac Forum

Coolant change on the '05 Deville


KHE

Recommended Posts

I changed the coolant on my '05 Deville this morning. I needed to remove the 20 push in fasteners that hold the air dam to the bumper fascia and the engine cradle. After that, the air deflector could be removed the the radiator drain was visible. I moved a wire harness out of the way but it still looked like coolant would drain on the harness so I shielded the harness with some aluminum foil.

I only got about a gallon out of the system by draining - even with the surge tank cap removed. I used the shop vac exhaust to blow out another half-gallon of coolant. The system capacity is 13 quarts so based on what I was able to remove, I'll need to change the coolant again in 24-27 months rather than 5 years since it is impossible to completely drain the system.

The drain was a lot easier to access on this car vs. the Sevilles but removing the air dam was sort of a PITA. I installed the bars leaks sealer in the upper radiator hose.

Kevin
'93 Fleetwood Brougham
'05 Deville
'04 Deville
2013 Silverado Z71

Link to comment
Share on other sites


Whats up with these radiator drain petcock? When i unscrewed it on my sts 95 it only dripped and i had to loosen the lower hose to get the coolant out! Seems to me that this drain plug is useless!

You do not get it , folks. GM just wants to do something about obesity epidemics. :D

The saddest thing in life is wasted talent

Link to comment
Share on other sites

On the 2005 DeVille, was there not a hole through the lower air dam with which to access the petcock? Some of us have made a tool from a short length of broom handle, just cut a shallow slot in the end, in order to loosen the petcock drain. This of course assumes that there is a hole present in the lower air dam, like on my 1999 Seville.

If I had a radiator drain petcock that didn't flow very well, I'd remove it completely in order to see if it was plugged up. If it still didn't flow well, and you had a way for air to get in the top (like opening the cap on the reservoir tank) I'd be concerned about a few other parts of the system. Depending on the design of the car, and I'm no expert on the 1995 Seville, either the air bleed hose or hollow bolt could be plugged. Niether situation is good! If air can't get INTO the system correctly, it may not be able to get OUT correctly either.

On this type of plastic plug, there is usually an "O" ring that holds the plug in place once it is completely unscrewed from the rad. Pulling on the plug then will remove it from the bottom of the rad side tank. I realize that this might involve completely removing the bottom air dam for easy access, but we all know that it can be done.

Never underestimate the amount of a persons greed.

Link to comment
Share on other sites

Whats up with these radiator drain petcock? When i unscrewed it on my sts 95 it only dripped and i had to loosen the lower hose to get the coolant out! Seems to me that this drain plug is useless!

It helps a lot to remove the surge tank cap when draining the coolant.

Thanks for posting

:nopicssmiley:

[Makes a note to get KHE a camera for his next special occasion]

Yeah, I know - I didn't take the camera out in the garage.

On the 2005 DeVille, was there not a hole through the lower air dam with which to access the petcock? Some of us have made a tool from a short length of broom handle, just cut a shallow slot in the end, in order to loosen the petcock drain. This of course assumes that there is a hole present in the lower air dam, like on my 1999 Seville.

If I had a radiator drain petcock that didn't flow very well, I'd remove it completely in order to see if it was plugged up. If it still didn't flow well, and you had a way for air to get in the top (like opening the cap on the reservoir tank) I'd be concerned about a few other parts of the system. Depending on the design of the car, and I'm no expert on the 1995 Seville, either the air bleed hose or hollow bolt could be plugged. Niether situation is good! If air can't get INTO the system correctly, it may not be able to get OUT correctly either.

On this type of plastic plug, there is usually an "O" ring that holds the plug in place once it is completely unscrewed from the rad. Pulling on the plug then will remove it from the bottom of the rad side tank. I realize that this might involve completely removing the bottom air dam for easy access, but we all know that it can be done.

There wasn't an access hole in the air dam for the drain plug - I wish there would have been. The air dam is a large plastic piece that is held in place by 20 push clips. Once the air dam is removed, the radiator drain is on the bottom of the radiator tank - it is a hex fitting and a socket and a ratchet can be used to loosen it. There are pegs on the fitting for tightening by hand. It is completely different from the older cars.

Kevin
'93 Fleetwood Brougham
'05 Deville
'04 Deville
2013 Silverado Z71

Link to comment
Share on other sites

I'll need to change the coolant again in 24-27 months rather than 5 years since it is impossible to completely drain the system.

I would not go 5 years even if I could get it all out.

That hole in the bottom of the splash shield is not all it's cracked up to be. Coolant does not come out in a nice stream. It sprays all over the splash shield and then drips from other places. It's MUCH neater to just pull the shield in my experience.

Link to comment
Share on other sites

I'll need to change the coolant again in 24-27 months rather than 5 years since it is impossible to completely drain the system.

I would not go 5 years even if I could get it all out.

That hole in the bottom of the splash shield is not all it's cracked up to be. Coolant does not come out in a nice stream. It sprays all over the splash shield and then drips from other places. It's MUCH neater to just pull the shield in my experience.

Larry,

The access hole must have been deleted from the splash shield in '04 or '05 - mine did not have one. There was a wire harness neat the drain and I knew the coolant would be all over the harness and drip everywhere so I used aluminum foil as a deflector.

I was thinking about changing the coolant evey other year since I could only get half of it out. What change interval do you use?

Kevin
'93 Fleetwood Brougham
'05 Deville
'04 Deville
2013 Silverado Z71

Link to comment
Share on other sites

Yeah, I seem to recall that wire loom Kevin. Really can't hurt much if some coolant gets in there as it is just a conduit and the wires inside are all insulated anyway.

I've been changing mine every 3 years, but I've been contemplating 2 for the very reason you mention.

Link to comment
Share on other sites

I'm thinking it might be a good idea to change mine since I have no idea when the previous owner did it last, if at all. It's kind of been changed when I think about it, since it did purge itself entirely onto the ground...and it took over a gallon of coolant to fill it back up, lol, but still.... My car was made before they introduced dex-cool, so it uses the green stuff. Do I have to use these GM coolant tabs I have read about when I change it? I was also told to be sure I use silicate-free coolant...which I'm pretty sure is all of them nowadays except that geo-5 stuff.

big4870885.jpg

Link to comment
Share on other sites

It would be a good idea if you don't know when it was last done, but then you said that it took over a gallon to refill what it lost. You won't drain much more than that so you've essentially done a change. GM no longer uses the tabs. I don't either, but it's a personal choice. They DO NOT cure nor prevent head gasket failures. They are to seal niusance leaks (like the one you posted) or porous castings.

Link to comment
Share on other sites

I'm thinking it might be a good idea to change mine since I have no idea when the previous owner did it last, if at all. It's kind of been changed when I think about it, since it did purge itself entirely onto the ground...and it took over a gallon of coolant to fill it back up, lol, but still.... My car was made before they introduced dex-cool, so it uses the green stuff. Do I have to use these GM coolant tabs I have read about when I change it? I was also told to be sure I use silicate-free coolant...which I'm pretty sure is all of them nowadays except that geo-5 stuff.

When refilling on the 94, use only the green coolant, or the Prestone suitable for green or orange. Drain as much coolant as you can, and at two year intervals, as it is difficult to get a complete drain.

Use Bars Leak Gold tablets or powder. It must be added to the top of the lower radiator hose. Do Not add to surge tank, it will not disperse properly and will cause clogs.

-George

Drive'em like you own 'em. - ....................04 DTS............................

DTS_Signature.jpg

Link to comment
Share on other sites

I changed the coolant on my '05 Deville this morning. I needed to remove the 20 push in fasteners that hold the air dam to the bumper fascia and the engine cradle. After that, the air deflector could be removed the the radiator drain was visible. I moved a wire harness out of the way but it still looked like coolant would drain on the harness so I shielded the harness with some aluminum foil.

I only got about a gallon out of the system by draining - even with the surge tank cap removed. I used the shop vac exhaust to blow out another half-gallon of coolant. The system capacity is 13 quarts so based on what I was able to remove, I'll need to change the coolant again in 24-27 months rather than 5 years since it is impossible to completely drain the system.

The drain was a lot easier to access on this car vs. the Sevilles but removing the air dam was sort of a PITA. I installed the bars leaks sealer in the upper radiator hose.

Something to consider the next time you need to change the Coolant-

This is my procedure for changing/flushing the Coolant. [summertime works best for this method]

Park with nose facing down/ raise rear-end to increase drainage

Operate engine until hot with heater on max., then shut off engine of course.

Loosen lower radiator hose, drain or Open Petcock . Then Reconnect hose/Close Petcock

Refill with only water, run engine until hot.

Drain again and repeat procedure until water runs clear [2,3, or 4 times].

For Drain Final cycle, Drain 50% of system capacity 6.5 quarts for 4.6L Deville.

Add 6.5 Quarts of 100% Dex-Cool. This will achieve 50/50 mix.

Run until Operating temp reached to mix coolant and water.

This is the procedure I have used for my 03 Deville [and all my other vehicles .for over 20 yrs. with appropriate specs and change intervals]

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...