2G 3.5 Coolant Crossover Seals

[n3wpv]

Does anyone have any instructions/photos for replacing the coolant crossover seals on a 2G 3.5L? I've seen mentions of it but haven't found any directions yet. Thanks!

[oldwino]

Removal and installation is about 5 pages in the FSM. Gotta leave for work in 10 minutes. Will post the pages tomorrow, if no one else does before then.

[n3wpv]

5 pages, wow. Maybe i should just let a shop do the work. Looks intimidating.

[oldwino]

If you want any of the other sections referenced, let me know.

[aurora2001tan]

If your not a good mechanic and dont have a shop, with a CAR LIFT. You are not doing this!

Alot of time is spent under the car. The back right manifold comes off after taking the transdipstick off. Before you do that you need to remove the s pipe from the exh to the cat.

The service manual is wrong, You dont have to remove the brake booster. or any of that. You do remove the egr and trottle body. dont remove cable. Jusy body and swing out of the way.

warning. there is a pipe that goes down into the right ( rear ) manifold. It is the sec inj system where air is blown into the exh. You should heat this up with torch and then remove. Do this before taking off the rear manifold.

Then with the manifold loose and flopping around you can remove the crossover pipe. Hope your pipe isnt in bad shape and need replaced. Some were bad casts. Then you can replace your crossover gaskets.

Instructions are kinda mixed up here. Dealer quoted me about 5 1/2 hours to do this. Its a sucky ****** job. NOT FUN TO DO! Best done at Your shop if your installing a new and rebuilt transmission. If not then leave to the pros. There are some special tools needed like long extentions and really a pros tool box.

I did this at 107k with car being almost six years old. At 233k the front lower one has seeped but I stopped that with seal tabs. I wont be doing it again! If its never been done before YOU HAVE TO DO IT. The OLD gaskets can burst and you would have coolant spraying all over the motor.

Last time i looked, it looked like on the 4.0 everything can be done up top without removing the right manifold.

[n3wpv]

oldwino - thanks for the instructions.

aurora2001tan - thanks for the info. I was quoted $700 from a local dealer. After looking into this I'm thinking that'd be money well spent. Fortunately it's not leaking bad. No puddles on the ground, just some residue around the crossover. Might see if i can tighten up some of the bolts for now.

[aurora2001tan]

[glow=red,2,300]DO NOT TIGHTEN BOLTS PAST SPECIFIED TORQUE. The gasket has a steel spacer in each bolt hole. That means it will only crush so far then start pulling the threads out of the motor!!! [/glow]
New gasket should have been based in Aluminum not plastic like the 3.8 intake gasket update.

I would insist the tech put some kind of sealer on these gaskets too.


107k miles 6 year old originals

[ntrenn]

Guys,
Saturday when we pulled in the drive, Intrigue 2 was steaming under the hood. Quick check showed one of the front crossover gaskets peeing like a little boy - nice rainbow of Dexcool.

As of right now, I'm halfway to getting it fixed - son and I got it apart yesterday. I've been taking pictures - hope they turn out.

For now - I think Tan is being nice about his description of the difficulty of this job. We even had to pull the sway bar and steering rack to get at the rear manifold bolts. Complete PITA. The car is in pieces all over the garage, the drive, and the sidewalk right now. Parts run this morning...

[ntrenn]

So....we have the car almost back together waiting on the throttle body coolant hoses from the dealer.

Over the last 3+ days, son and I have been wallowing around on the ground cussing the dingbat that designed the crossover in such as way - just a little allowance and all would have been so much easier.
The basic procedure:
1. Drain coolant (if it hasn't already leaked out)
2. Remove Throttle body and inlet hose.
3. Remove throttle body spacer and hoses
4. Remove sway bar
5. Remove steering rack (not sure if necessary on an Aurora)
6. Remove front air deflector (pan on Aurora)
7. Unbolt exhaust crossover junction just behind radiator.
8. Unbolt EGR outlet tube (almost completely blocked off with crud)
9. Loosen EGR inlet tube at the crossover
10. Remove heater hose from crossover rear.
11. Loosen rear EGR fitting to rear manifold (1-1/4 wrench)
12. Unbolt exhaust pipe from rear manifold - or just leave it connected.
13. Unbolt rear exhaust manifold.
14. Remove transmission dipstick (take dexron bath) and then remove the last manifold bolt.
15. Lift manifold up and to the left to clear space to unbolt the crossover
16. Remove upper motor mount (Intrigue only) (partial until crossover is loose)
17. Unbolt crossover and pull it out.

While in there, we also worked on a few other things....the brake line feeding the RF wheel was seeping brake fluid right where it had been touching the firewall insulation - I figure it was from the insulation retaining water.
We also changed the intake manifold gaskets which necessitated removing fuel lines and the like.
There was evidence of leaks at both the intake manifold gaskets and the throttle body heater. The TB heater had been drinking its share of coolant.
Stoned all of the surfaces flat before reassembly.
Back together with Felpro gaskets.
Buy some extra manifold bolts....you're going to need them as when they drop they go into nomansland between the engine and the tranny.
I'll have a spare manifold gasket for a the next brave soul that wants/needs to attack this issue on theirs.

Easily could be $1000 job in a shop if you do it right and fix everything correctly while in there..

My son is now emboldened to do just about anything on this car as he's had almost 2/3 of it apart just this week.....couldn't have done it without his long skinny hands to reach in the tight places.

[ntrenn]

Apr 14, 2012 4:49:43 GMT -6 n3wpv said:

5 pages, wow. Maybe i should just let a shop do the work. Looks intimidating.

Should be 10, but they cheat by sending you to other sections to do the hard stuff.....

[rorafan]

Good gawd that's a lot of steps. Glad to hear it's just about back together. Good learning experience for your son too!

[ntrenn]

So...here's my contribution to the photos of leaking coolant crossover gaskets.

imageshack.us/photo/my-images/545/dscf4413i.jpg/



I sure hope Fel-Pro has done a better job on the new ones.....

[Randy T.]

The part number for the gaskets are Felpro Part Number: 35722, I think you need 3 of the gaskets, about $10 each at local parts stores.





Added to 2G stickies for future reference.

[Randy T.]

This job was going pretty good until I discovered the flaw in the coolant crossover, the crossover is being sent to the machine shop in the morning to see if they can mill it flat. I hope to get some better pics tomorrow, underneath, too.

[ntrenn]

Randy - pull the TB heater manifold and stone those surfaces too. Those were more out of flat on my car than the coolant crossover surfaces. Check the feed hoses to it as well - I had one that was a little soft so I got new from the dealer through Vintage Parts. You might consider aviation sealer on the gaskets, but the book doesn't call for any sealer at all and the Fel pro gaskets seem to be a little better at holding together than the factory ones.

[Randy T.]

Thanks for the advice, I will check those parts out.
Got the crossover cleaned up, about 20 minutes and no charge, it was at a machine shop where I had my first job. Had so much going on today, I did not get very far, but I should easily finish it tomorrow.

Here are some more pics with my regular camera, I did this on the pit instead of the rack, worked out pretty good.

















You could still kind of see the mark, but it is a big improvement on what it was.

[ntrenn]

Great pictures - kinda brings back bad memories...
You have more tunnel room on the Aurora than the Intrigue. I was unable to get the exhaust collector bolts loose, so I ended up leaving them on, but I had to pull the rack to get to the rear manifold bolts. Dropped a couple of those bolts putting it back together and they go off into nomansland between the engine and transmission.

Don't you love that bolt hidden behind the TB gasket...

[aurora2001tan]

Very sucky job. A pit or a Car lift is a must, then you can get to manifold bolts without taking off rack. Cant imagine doing on ground. Not at my size anyway.

[Randy T.]

I don't remember a hidden bolt behind the tb, must have just ripped it off. lol.

Well bad news on the crossover job I did, the head gasket is now leaking on the motor. I kept getting coolant on the area below the intake, but could not find a leak. I pulled the intake and I know have it under pressure, about 15 psi. I can see coolant actually leaking from the rear head gasket itself. On head gasket jobs on these, are the head bolts known to pull out like the v8s do?

[ntrenn]

It's the bolt that still in the TB adapter in this photo. Maybe they changed them by 2001, as I've noticed that there are really slight differences between the Aurora and the Intrigue LX5.

Bummer about the HG leak. Not sure about pulling threads like the 4.0 or just leaky gaskets. May get the chance to find out here in a week or so when the Dayton express rolls into the drive.

[Randy T.]

I may be getting a chance to find out in a week or so, too. My tb gasket tore in half, so if the bolt was hidden, it could have been exposed at that time.

If anyone else is doing the crossover seals, I would recommend pulling the entire intake instead of just the throttle body. I pulled an intake yesterday to look at a hg leak, and I noticed it really opened up the work area, visually, and physically. It does not take much longer to pull the intake, special tool needed is a $10 fuel line release kit from the parts store. If you work on your own car, you need these anyways.

[ntrenn]

I think they eliminated the 4th bolt on later models as if you compare the '99 photo with the '01 photo, the 4th screw insert is missing on the intake manifold.
X2 on pulling the intake - the gaskets are $5 and renewing them is always a good thing as is cleaning the coolant puddle in the valley. Also gives you the chance to check the backfire valve (at least on the Intrigue).

[canaboy]

Although the above mentioned procedure might be a better way for some, for us in Canada, corrosion to exhaust manifold nuts and bolts could be a problem for rear manifold removal, especially on cars over 200km.

The way I did mine two years ago was :-

Remove EGR , and pipe ??

Remove throttle body and other small stuffs that's in the way

Undo the front EXHAUST manifold "DO NUT" flange bolts

Remove the COOLANT cross over pipe bolts and let them go against the EXHAUST CROSS OVER

USE A NEW HACK SAW BLADE and cut the COOLANT cross over bolts shorter so that you have enough room to undo those bolts completely from the engine.

Once all the bolts are removed, you can replace the gasket with the coolant cross over resting between the EXHAUST and the engine.
Or, you can remove the coolant cross over completely from the engine by using a crow bar on the EXHAUST CROSS OVER, since you had the front exhaust flange undone.

Use shorter bolts ( two bolts I think ) to reinstall------- 2 or three threads shorter?? may be.

Does not matter which route you prefer, either do it according to the book or my way, it is a real pain to do and takes lots of patience and back muscle endurance, but it can be done.



Surprisingly, those bolts are easy to cut through using a new hack saw blade from Home Depot.

EDIT:_ I assume you drain the coolant first.