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I started the coolant crossover reseal today

22048 Views 53 Replies 13 Participants Last post by  ThisoldCaddy
I'll begin here

I have decided on an alternate approach

I am about 1 hour into it & have drained, removed the belt cover, dogbone & mount, tensionor various hoses, EGR lines, TB & TB plate, EGR, Fuel line, (I have the plastic fuel rail) steel tube in front

Its looking real funky at the TB & inside the intake.

THis is the actual failed gasket that is about 1/8th in. thick & you can see the Black part of the gasket has cracked & split away exposing the red silicone allowing it to push out & leak. this leak was intermittent & wouldn't leak until it was fully pressurized But it would also leak about a 1-1/2qt sometimes as the car sat

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Check out the build up on the new pump after 20,000mi. I have flushed the system & added fresh dexcool 3 times over 60,000mi. I am currently having a major fight with the lower rad hose clamp that is at an angle that nothing I have will swivel to that angle. So far that is the only hurtle but I am preparing to remove the lower port bolts and it look's like a PITA.

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For sure time for a TB cleaning. I like your approach looking towards the end of the day with the cold one's. Be careful with the plastic fuel lines they don't like to be moved around much after being on the car for sometime.
The green fluid in the pump volute and the crossover indentation is DEX-COOL ??
For sure time for a TB cleaning. I like your approach looking towards the end of the day with the cold one's. Be careful with the plastic fuel lines they don't like to be moved around much after being on the car for sometime.
I may remove & go have the intake cleaned. I am thinking of pouring some hot water on the plastic rail lines before flex & secure them out of the way, if I don't have clearance I will just remove the rail. so far so good but I am loosening the rear lower port bolts and the first one closest to the firewall and I am looking into removing the trans. selector device right smack in front & see what all that may involve. This car has 105xxxmi on it and that is alot of crud living in the intake. I don't drive it very hard.
The green fluid in the pump volute and the crossover indentation is DEX-COOL ??
I topped it off with Walmart extended life 50/50 knowing I would be adding a compleate fill of fresh dexcool in the very near future, all the drained fluid in the pan is orange/pink with a hint of green, its odd it did'nt mix up that much after driving 30 miles. I may have added 3qts 50/50 & tap water.
I may remove & go have the intake cleaned.
Not worth the time and effort. That black crud would accumulate again in a year or two. Completely normal since there is no fuel flowing through the intake manifold to flush out that buildup of unburned PVC system nasty stuff.

It would be worth cleaning the throttle body periodically.
Well, battles were fought with the lower port bolts the firewall side being trapped and better removed in proper sequence of the front rear bank lower port bolt being the better first bolt to remove. The shifter input hardware & module need removing to access those bolts slightly easier. The harness was a real SOB moving it around to gain tiny bits of room to work the area at that rear bank lower port.

The front bank lower port was a lesser battle but still a dirty fight. The harness ground bolt on the 96 model is on the block near the frt. OX2 sensor and buried behind several harnesses & trans. cooler line hard to get out but a must to allow more harness movement. The circular part of the seal at the upper port in this picture is were this gasket blew out. it just deadheads at the head.

you can see the upper ports on the 96 year are not the same as the later models

The black gasket material that supports the silicone inlay just deteriorated away & fell apart The other gaskets all stuck to the block port and appear good still doing there job. I see the upper gaskets to have the flaw of not enough support by the fasteners. The upper port in this picture is the point if the leak

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This disassembly was a real difficult task, the lower portion is just very very hard to do simply put. Alot of components need to move out of the way and then it still very difficult. The transmission & harness are in the way of the lower bolts in a bad way. Now I get to mentally prepare myself to assemble it correctly. The dissassembly took nearly of four hours for me, A 13mm swivel ratchet wrench & 13mm shorty ratchet wrench. would have made things slightly easier maybe. The harness really sucks.
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You can deal with the harness a little more easily if you disconnect the ECT sensor and disconnect that ground lead.
That should be easy with the crossover out. Be careful if the stud starts to turn when you loosen the nut (on the ground) you have to stop and find a way to hold the stud. If it keeps rotating it will break the lead off the ground wire.
This crossover is easier than some, the newer ones have the throttle body spacer built into them so you have to deal with that too.

Also, be sure to replace that green hose.
Oil down the nipple and slide the hose on too far, get the clamps on, then when you get the crossover back on slide the hose on to both nipples and tighten the clamps.
Be careful of the clamp orientation so that you can get tools on them. Put the screw on the bottom facing the driver's side.
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Today I just cleaned up things taking a couple hours to make things ready & collect a few more parts to make sure I don't have to do this again because I neglected to. I started under the hood wet sanded the awkward ports and did some degreasing using some brakeleen & Dawn dish soap hot & cold water. Dawn is the deal. A great degreaser. Also shooting the garden hose nozzle in the upper ports and thru the steel tubes yeilded some some muck down to the floor and I have now done the most thorough flush outside of boiling the block.

It ends up the crossover port that failed is a useless port deadheading at the head for the EGR that puts high temp exhaust gas to the gasket that is totally unnessesary. you can see the carbon crud build right on the port that was poorly thought out. A mini frost plug or no port would be a better engineering plan. This must be due to a liberal California conspiracy.

I did clean & paint the crossover manifold and it's very clean and pretty. I chose to re-use the previous/original waterpump cover but will use a new gasket. the thermostat is new, I took advantage of the afternoon sun to set the paint up. I did mask all seal surfaces off. Elbow grease with hand wire brushes took some x-tra time. (Rustoleum Hardhat aluminum & clear coat. Good rattle can stuff.

Unlike cast iron, aluminum corroides far more than iron rusts without compromise to the integrity of its strength.

I do need to put fresh stubby hoses connections on the rear bank area, I dont want to do this twice.

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My case of Lienenkugel's is half empty now.
NEVER re-use those green hoses.
You wouldn't believe how hard those are to replace without removing the crossover.
NEVER re-use those green hoses.
You wouldn't believe how hard those are to replace without removing the crossover.
Thank you ewill3rd for stepping in. I did my best to get background before jumping into this task but I need to get the car straight again. I will prevail, tomorrow I will install only the crossover and thats it due to other commitments. The thing will go back on leaving only the many other installations to complete. Its a definate plan.
I have began reassembly & the crossover went on as expected. things are moving along without much problem. Putting the bolts in the manifold held the gaskets in place well although the rear bottom port fell off one bolt but was able to get all bolts started and went back to the lower rear & was able to jiggle the crossover and move the gasket back into alignment and started. The rear stubby hose added troubles. I had a little bit of trouble fitting the EGR tube on the back side- its easy to distort the orfice of the tube aligning it and had to stick a ratchet handle in the tube & form it round again.

This plug connector I don't remember unplugging and wonder if it is a just a extra for a 96' model that has more options. it originates at the harness that goes over the top of the trans. and was hanging down if the front trans. area.

It looks to have 2 female spade terminals. I don't think I unplugged this connector. Can someone identify this for me.

I thought it may be the left fan but don't see a terminal on the fan and I didn't unplug the left rad. fan.

I can account for all other connections.
Is this for optional equipment?
2 wires black & white.
If no one knows, I will just let it lay down there were I found it.
I am guessing its for optional equip.
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Looks like a cooling fan connector to me. Check the left side cooling fan.

I think it plugs straight in from the bottom and it is really hard to see, it is just a hole.
Look around the fan motor to see if there are wires in it, if there are no wires, that goes in there somewhere.
how critical is it to use the OEM green hose there ?? i've heard some swear that if you use regular heater hose you'll be in there soon replacing it with the OEM green hose
The green silicone hose is important. My understanding is that it is used because it is more heat resistant and used because it is so hard to get to.
that's what i've been told - it's super expensive so people tend to balk at the price
Get the green hose, don't screw around with that one.
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