AOS/OVS Leaking Coolant! Drop Engine?
#31
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Not worth the risk of her getting hurt in the process.
When she's sick of you and actually wants to go through with it, she'll start mixing small amounts of all the fresh coolant you've drained on a monthly basis into your drink or food until you start getting sick and the doctors can't figure out what's going on. :devil:
When she's sick of you and actually wants to go through with it, she'll start mixing small amounts of all the fresh coolant you've drained on a monthly basis into your drink or food until you start getting sick and the doctors can't figure out what's going on. :devil:
#32
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Not worth the risk of her getting hurt in the process.
When she's sick of you and actually wants to go through with it, she'll start mixing small amounts of all the fresh coolant you've drained on a monthly basis into your drink or food until you start getting sick and the doctors can't figure out what's going on. :devil:
When she's sick of you and actually wants to go through with it, she'll start mixing small amounts of all the fresh coolant you've drained on a monthly basis into your drink or food until you start getting sick and the doctors can't figure out what's going on. :devil:
DS
#33
Instructor
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When I did mine it was a right PITA.
I diassembled the top of the engine and lowered as the guys had mentioned. You can then access the AOS (I changed the o rings on all the aos fittings).
The problem I had was the rear bolt on the AOS had siezed, the one nearest rear of car came out no problem. I ended up dremelling the head of the siezed bolt off. I then removed the AOS and used heat and a stud remover to get it out (the kind thats a bit like a drill chuck).
What's required is straight forward, working in the tight space for a long period is frustrating, if you have a problem.. I had bruised knees from kneeling behind the car for a day!!! If you do need heat like I did, make sure you find something to protect the fuel lines and sound insulation (I used some old heat shields.
If you have other things you plan to do, I'd drop engine if I was you to change the AOS, if you just need to change the coolant pipe, I'd just do that and leave the AOS till you have the engine out. The coolant pipes go into the top of the AOS so should be easy enough with the engines lowered a little and near side inlet manifold off.
Good luck!
I diassembled the top of the engine and lowered as the guys had mentioned. You can then access the AOS (I changed the o rings on all the aos fittings).
The problem I had was the rear bolt on the AOS had siezed, the one nearest rear of car came out no problem. I ended up dremelling the head of the siezed bolt off. I then removed the AOS and used heat and a stud remover to get it out (the kind thats a bit like a drill chuck).
What's required is straight forward, working in the tight space for a long period is frustrating, if you have a problem.. I had bruised knees from kneeling behind the car for a day!!! If you do need heat like I did, make sure you find something to protect the fuel lines and sound insulation (I used some old heat shields.
If you have other things you plan to do, I'd drop engine if I was you to change the AOS, if you just need to change the coolant pipe, I'd just do that and leave the AOS till you have the engine out. The coolant pipes go into the top of the AOS so should be easy enough with the engines lowered a little and near side inlet manifold off.
Good luck!
#37
Race Director
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I had a cat go bad, so replaced everything including headers all the way back to tips, all four O2 sensors too, just because they were old. Did the LN IMS, RMS, replaced AOS, water pump, fuel pump, spark plugs, hoses, front rotors, yada yada yada.
Replaced the OEM radio with double-DIN satellite radio/telephone/navigation system.
Even got a new set of center caps because one of the old ones was a bit discolored. Oh, and a new cigarette lighter (even though I don't use it) because the little cigarette icon on the front was worn and it bothered me.
Yesterday, I ordered new leather because my driver's seat is worn on the bolster.
Money pit? Sheesh. I've spent more on PM than I paid for the whole car. But, I'm loving the car anyway!!
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
I enjoy each and every drive more than you can imagine.
At least KK has time and space to work on it. I have neither, other than for the minor stuff I can get to without an engine drop like fabricating eucalyptus wheel spacers and brake pads). So, my indy prolly can buy himself a new 991 on my dime.
#38
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KK, a serious question. Have you considered a Ferrari? I heard those are great cars but needs tons of repair and PM, engine out to boot!
Seems even better than a Porsche for you?
Seems even better than a Porsche for you?
#39
Drifting
Thread Starter
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Cuda, that really sucks. I just thought I had it bad.
Strange you say that because my next one may be something like a Ferrari 430 coupe even though my wife wants a Maseratt GT. Both sound like a blast to work on. I would like to keep the C4S though I dont know why, and add a TT or GT2 instead.
My project would have been finished today but apparently "overnight" shipping means 4 days for FedEx.![banghead](https://rennlist.com/forums/graemlins/banghead.gif)
I would like to thank all for the great DIY's and tips!
KK, a serious question. Have you considered a Ferrari? I heard those are great cars but needs tons of repair and PM, engine out to boot!
Seems even better than a Porsche for you?
Seems even better than a Porsche for you?
My project would have been finished today but apparently "overnight" shipping means 4 days for FedEx.
![banghead](https://rennlist.com/forums/graemlins/banghead.gif)
I would like to thank all for the great DIY's and tips!
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#40
Race Director
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Cuda, that really sucks. I just thought I had it bad.
Strange you say that because my next one may be something like a Ferrari 430 coupe even though my wife wants a Maseratt GT. Both sound like a blast to work on. I would like to keep the C4S though I dont know why, and add a TT or GT2 instead.
Strange you say that because my next one may be something like a Ferrari 430 coupe even though my wife wants a Maseratt GT. Both sound like a blast to work on. I would like to keep the C4S though I dont know why, and add a TT or GT2 instead.
I keep looking at Ferrari's and Maserati's too, and plan to get a TT some time in the next year or two. And I'll keep the C2.
New door:
#41
Pro
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I ended up removing the intake after the AOS was off. I then installed the new AOS and connected all the hoses, but to install the intake I had to loosen the AOS bolts so it could be tilted back enough to allow a socket to fit on the rearmost intake bolt, then retightened.
I'm also doing the RMA and IMS and so much has to be removed the only thing left to pull the engine is to disconnect the fuel line, electrical cables, and coolant hoses and the engine falls out. My advice is to remove the engine and be done with it. I will never attempt to do such in-depth maintenance again without removing the engine - it's just not worth the frustration. The 996 is engineered to be assembled and to run, but to perform all but basic maintenance one has to peel back each layer of the onion until arrival at the part to be replaced, and each layer has a specific sequence and procedure that must be followed to remove it.
If that wasn't bad enough, after the engineers designed the motor they stuffed it in a hole so it was impossible to reach anything...
#42
Drifting
Thread Starter
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The AOS blocks the rearmost bolt on the intake making it impossible to fit a socket on it
#43
Instructor
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I have a 2002 and it bolts from above. The only way to remove it was with the transmission out. The AOS blocks the rearmost bolt on the intake making it impossible to fit a socket on it, so I had to remove the AOS from the flywheel side. The AOS bolt next to the intake was blocked by the hoses above and could only be removed from the flywheel side with a 1/4" drive ratchet and a deep socket and then only a couple of clicks at a time.
#44
Captain Obvious
Super User
Super User
#45
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I just wish all the nice cars had the AOS in an easy accessible location. I haven't come across any yet where you don't have to drop something, have small hands that can contort, take off half the top end, or make your own tools.
Oh, it would help if manufacturers wouldn't use plastic as heat and cold will make them brittle over time. I'd rather have rubber swell at least from the hot oil than plastic break. Of course manufacturers like BMW does use some rubber hoses but they tend to break at the hose clamps since the hoses are usually a few mm too short and under constant strain from the movement.
Oh, it would help if manufacturers wouldn't use plastic as heat and cold will make them brittle over time. I'd rather have rubber swell at least from the hot oil than plastic break. Of course manufacturers like BMW does use some rubber hoses but they tend to break at the hose clamps since the hoses are usually a few mm too short and under constant strain from the movement.
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