So I went through the JTIS proceedure for coolant change on a supercharged car.

They want you to go through three seperate phases in order to bleed the air out of:

Intercooler system
Heater
Main cooling system

Their proceedure involves a number of cooling off periods and always with the cap in place. This involves a lot of time.

I understand their cautions about watching for air bubbles and the temp gauge.

But as with all cars once they've been getting serviced for a while maintenance tips and shortcuts (that work) become known.

I noticed that they don't mention draining the block.

1. Is it too hard to get to the block drain or does it drain by design anyway?

2. If you drain the system just via the radiator petcock how much coolant is left in the system?

3. Are all 3 of the intercooler heat exchangers completely drained when you drain the radiator?

4. Should one open the "supercharger fill port" while draining to facilitate a full drain?

5. Are there any hoses that should be pulled off to make this proceedure work better?

6. I haven't had a look at the Supercharger fill port sealing washer. So is it an O-ring or what and does it really need to be replaced as suggested?

7. Finally, when I fill cars system I typically leave the expansion tank open and try to bleed as many spots as I can in one shot. Then let it completely warm up test the heater etc. This usually works with one follow-up burping of the system. The JTIS shows three steps and cool down periods. Is there any reason I can't do this as I normally would if I'm being observant?


When I haven't been able to completely drain a cars cooling system I've used the repeated filling with distilled water proceddure until the overall color is "close enough" to clear.

Then I drain the system and put half the system capacity worth of coolant in and fill the rest of the way with water again.


Any tips would be greatly appreciated?

Thanks

Bob S.

 

I'm aware of the two large SC intercoolers. By the 3rd I think you mean the front radiator. I guess (!) it has its own drain plug.

I find parts dept guys helpful and I asked mine about the SC fill port. He said their techs don't open that port and they bleed fine. Also, I know my car had its coolant replaced by another garage many miles away and they didn't open that port judging by the state of the washer/etc. I believe it's that really BIG hex up top front by the 2 intercoolers. Maybe it's shown somewhere in the drawings in this http://www.drivehq.com/web/jfenley/P..._2000-2005.pdf

I usually bleed the way you describe, but as you noticed jag basically say not to (unlike the original, and of course non-STR, cars). I'm planning to stick to my usual way initially but be especially vigilant. As it gets hottish I plan to install the cap. But what I'd really like would be a better way to monitor engine temp. There's no CHT (cyl head temp) on the STR which would've been handy. Maybe EOT (oil) would do. I'd hate an overhot engine or boiled over coolant.

 

So the "radiator" for the IC system has it's own drain plug?

The way it's described in the JTIS isn't particularly clear.

I actually found the big hex plug in the JTIS but I haven't tired to locate it on the car yet.

Maybe they're so particular about their filling & burping methodology because of the way the IC system is tied in with the main cooling system. It might burps better their way ???

I have another car that has a special burping issue where people have indeed over heated a head and ruined the engine. I added a special burping port with a piece of small ose that has a brass fish tank valve on it. That one works very well. It takes several times to burp it but you don't have to open the cap or cool the car off. You just submerge the hose and valve in a container of coolant then bleed it until the bubbles stop.

Thanks.

Bob S.

 

I guess it has its own plug. It's a radiator.... so it likely does
If I could've removed the car under shields etc easily when I tried to, I'd know, but I had a $*!& struggle and ran out of time and enthusiasm.

To marginally excuse JTIS, it's aimed at jag techs who've had training. Sure rules me out.

IIRC, you can't miss the big hex if you just take the SC engine top cover off. It's held on by 4 rubber lumps (about half-thumb size, I guess) which sit on little posts. The rubber parts are in thin, easily broken plastic in the engine cover and one of mine was broken when the car was inspected so take it off gingerly (er, may be a Brit expression - means with care).

Mine's an awkward SOB to get all 4 rubber fasteners back on the posts. To avoid damage to the thin plastic parts I make sure to press the top of the rubber when refitting. (I bought another top cover).

I like the sound of your burp-assist. If you figure one out for the STR please post details!

My feeling is that they built the sort of quantity of STRs that some careful babying was acceptable, maybe they're even over-cautious. But... if the detailed burping is vital I reckon by now there'd be a warning TSB about it (because the average tech just isn't going to follow the official procedure otherwise, and maybe not even then) and I don't think there is.

There again.... my intercoolers feel HOT (as in: very) and I wonder if they're not fully burped. I'm not getting any IAT2 codes (or others, touch wood) so I suppose it must be OK.

The cooling circuits just look to be sharing a header tank, which seems sensible in terms of available space under the hood (and harmless if all is OK).

 

It sounds like I'm going to have to put the thing up on jack stands and remove the belly pan to do a proper job of this. On the diagrams I see the support rails inboard on the frint so those could take jack stands but are the jacking points with the in-car jack at the outboard edge then? Seems like they must be?

My other car with liquid intercoolers has no drain at all for the radiator portion or the system but it's not integrated with the engine's cooling system. It's also easy to get at all the stuff compared to the JAG.

Bob S.

 

The rails are long enough to get jack + axle stand on a single rail if you wish, such as when just wanting to remove one front wheel.

There are at least 2 under shields. I meant the front one (from JTIS, I think it then exposes a radiator under shield but didn't get that far). The rearward of the 2 is the one you take off to change oil but doesn't look to help get at the radiators (I took it off anyway). Each shield has a zillion fasteners, of varying kinds

 

#2: It doesn't get all of the coolant as spec in the manual. It takes about 8 qts to fill back up (1 gal coolant, 1 gal dist. H20).

#4: I did a normal drain via radiation and took off the hoses to the SC to remove the expansion tank to check out a leak on the distribution manifold. After topped off, I opened the SC port and it was full - only able to add less then 100 mL so may not be necessary to check this but its pretty easy to do so (I figure its worth it for peace of mind).

#6: Stopped by the dealer to get a new washer - they didn't stock it. Have removed it a few times, still doesn't leak so reusing it is ok

few other tricks that worked for me:
When bleeding, before the engine gets hot, I move the car into 3 positions - level in the garage and pointed up (so the bleed point is the highest) on the driveway the back to level. I checked it a few times afterwards (drive car to run errand, wait till car cools down, open expansion port, add coolant until coolant runs out the expansion port) and its been fine (the 1st time all most all of the air out).

To remove the SC cap, I threaded a nut onto a bolt of the right diameter with them timed together (flats parallel). It turns out the allen slot is pretty deep and its gets the head of the bolt + 1/4 of the nut. It spins out easily with a wrench and you can torque it back up

If you fill it with water and run the engine to dilute the remaining coolant that doesn't drain, at the end, you have replaced what doesn't drain with mostly water instead of the 50/50 mix. When your fill back up with 50/50, your not going to get 50/50 mix but (50-x) coolant vs (50+x) water. You can estimate the remaining capacity as factory fill spec - 8 qts) and adjust as a target point (add X/2 more coolant). What I did was to mix up a batch of 50/50 and get one of those coolant meters and see how many ***** were floating (their scale is for regular green coolant not the DexCool) and double check after running the car for a while with the heater on max after it cools back to room temp. When I did it, I didn't know how much I had to add back so I had to adjust it afterwards but should be easier knowing that it takes somewhere between 7 to 8 qts to fill back up.

 

Thanks.

Yes I figured it didn't drain completely. So I'll just use the repeated fill with water method.

It's easy to obtain a 50/50 mix. Just measure how much you have to add to fill it on one of the flush cycles. From there it's a simple calculation based upon the the total capacity. But as long as you can get 50% of the antifreeze required for a complete fill in first then you just add water as the top-up and in the burp phases. Also, a 53 or 47% mixture isn't going to do any harm if you're off a bit.

But am I correct in thinking you HAVE to drop the belly pan to get at the drain (s)?

Did you find a drain on the IC "radiator" and use it?

Thanks.

Bob S.

 

I didn't drain the IC rad. For the main rad, you can see the drain from the front grill and if your hands were small enough, you could reach it through the brake air duct. Most likely you can't so you have to drop the shroud that covers all of the radiator. I not sure but I think the 3 front bolts of the engine pan attaches to it.

The pan is pretty easy to remove so I do it all the time. Its good to look for orange drops on it that may suggest a coolant leak. You may be able to drop the radiator cover without totally removing the entire pan.

 

Ah. You have the facelift (2005+) STR. Mine doesn't have that.
Wow. They really changed it. Again, not on my 2004 STR.

 

My is also an 04. Just got the jacking up part down ...too much practice

 

Jacking isn't too bad, though I'd have been happier if those front rails were further from the centreline.

 

You mean you remove the pan under the oil filter or the one forward of that?

 

There are just too many pans, the one under the engine and oil filter has three bolts that I believe goes on to the cover over the radiators. Not sure if your need to totally remove that pan, but it may be simpler.

 

Anyone know the exact size of the SC fill port ( that large Hex btw the two SC Coolers)?
Secondly the jtis mentions to open it up and top it off but is it really necessary? Won't just adding/topping off coolant from expansion tank be enough for it to recirculate the coolant into the two SC coolers? Thanks in advance.

 

Are you performing a coolant exchange or what exactly?

 

To make story short, I had the expansion tank and DCCV changed out few weeks back, but the mechanic never opened up the SC filler port like JTIS recommends. He did everything else following protocol except topping her off from the SC filler port.
STR runs perfectly fine no air pockets no over heating. But, I"m abit skeptical that the coolant hasn't fully filled up the two SC coolers. So basically I want to open up the SC filler port and top it off if necessary to make my mind at ease.

*Technically in my understanding won't adding coolant to the expansion tank recirculate the coolant all over even to the SC coolers?

 

If you want to change the coolant in the IC system then you need to disconnect the hose involved and drain/pump it out. You don't have to bother with that bleed plug if you don't want to. You can bleed/burp it via one of the hoses that leads up to the reservoir. I forget which one. It didn't take very long to figure this out. I also had the belly pan off because I WAS doing a full coolant exchange.

If you're worried about any coolant that drained out during the repairs I kind of doubt that. But just burp the thing to be certain. It's effectively a separate system. Only the expansion tank is shared.