Exaust Manifold Replacement - Toyota Nation Forum : Toyota Car and Truck Forums

91SuperWhiteII · 08-28-2006, 02:06 PM

So the exaust manifold on my 91 Corolla has been cracked for who knows how long. I finally decided to shell out the 60 bucks for a new manifold and gasket set off ebay. Im pretty sure corolla manifolds have a common problem with cracking so I was wondering if any of you have changed the manifold before. I'm kind of worried about breaking bolts off in the block or in the flange because most of the heat shield bolts broke off when i tried to remove them. I'm planning on soaking all the bolts down in penetrating grease of whatever its called but are there any other precaucions(sp) I should take? Is removing the old gaskets going to be a biotch? Thanks in advance

Flashmn · 08-28-2006, 02:13 PM

penetraing oils are a joke. Only way to get the rust out of them is to heat them with an oxy-ace torch.

91SuperWhiteII · 08-28-2006, 02:26 PM

oxy-ace torch huh? sounds inexspenive andpractical.

TheOtherCarolla · 08-28-2006, 03:13 PM

oxy acetalene torch, ie, a common welder. kinda pricey, but not really for the trouble it saves you. i need to buy one to get some rusted/stripped out bolts out of my 73 torino.

tashirosgt · 08-28-2006, 03:37 PM

I've replaced the manifold on a 1990 Corolla and taken old 4AFE engines apart. The little bolts that hold the heat shield bolts always seem to break off on an old manifold. But the big bolts that hold the manifold itself did not. The biggest problem for me was removing the nuts on the other end that hold the oxygen sensor. I think the pentrating oil there is a good idea. I ended up removing the old bolts with a nut splitter and I got new threaded studs to use with the new manifold.

89yotarollagts · 08-28-2006, 07:24 PM

i had issues with removing the manifold from the d/p which in return made me buy a header

***REN69*** · 08-28-2006, 07:39 PM

I'm thinking of finally putting my header too, anyone have any pointers on taking the 4AGE manifold off??

89yotarollagts · 08-28-2006, 07:43 PM

i dont think you have to worry about it ren its pretty easy, your new header should come with a d/p my biggest issue was sepperating my manifold from the d/p What kinda header you get ?

***REN69*** · 08-28-2006, 07:49 PM

its a KBD header, it was already installed in someone's car, so basically he did all the guessing work for me and said it should be ready to bolt on.

89yotarollagts · 08-28-2006, 07:50 PM

ohh cool, if you got an OBX id give yea some advise but no need to now.. bet you cant wait huh lol headers kick ass it deepend the sound & less raspy

***REN69*** · 08-28-2006, 07:56 PM

I can't wait man.. I wish I had more time to do it, it be done already! LOL!

thespud · 08-28-2006, 09:03 PM

The manifold removal is quite a simple proccess. The bolts have never snapped on me and i have removed the manifold a number of times before i finally swapped the engine out. Just for reference - If you are putting penetrating grease on there - put something like CRC 2-26 on there. It is non-flamable so even if the engine and manifold are red hot it wont flash up on you...

And yes, the cracking of the manifold is a fairly common problem, although, mine happened when my mother reversed into a speed hump and pushed the whole exaust forward

91SuperWhiteII · 08-28-2006, 09:23 PM

Quote:

Originally Posted by thespud

The manifold removal is quite a simple proccess. The bolts have never snapped on me and i have removed the manifold a number of times before i finally swapped the engine out. Just for reference - If you are putting penetrating grease on there - put something like CRC 2-26 on there. It is non-flamable so even if the engine and manifold are red hot it wont flash up on you...

And yes, the cracking of the manifold is a fairly common problem, although, mine happened when my mother reversed into a speed hump and pushed the whole exaust forward

ah thanks that was what i was looking for.

CRC 2-26, something i could find at autozone ect?

thespud · 08-28-2006, 10:32 PM

Probably best to go to a hardware store to get it altho autozone might have it. Its in the Blue colour can, and will have something like 'safe for electrical systems' on it, but it is exactly the same as CRC 5-56 (The red one), but it's non-flammable so it can be used on electrics and hot surfaces...

retiredat44 · 08-29-2006, 08:02 AM

Quote:

Originally Posted by tashirosgt

I've replaced the manifold on a 1990 Corolla and taken old 4AFE engines apart. The little bolts that hold the heat shield bolts always seem to break off on an old manifold. But the big bolts that hold the manifold itself did not. The biggest problem for me was removing the nuts on the other end that hold the oxygen sensor. I think the pentrating oil there is a good idea. I ended up removing the old bolts with a nut splitter and I got new threaded studs to use with the new manifold.

yeah, the little bolts are so freaking cheap, feel like Toyota scammed us on those, they break of if you sneeze on the little heat sheild bolts... amazing they got away with pulling that crap..

best you can do is soak bolts and threads with penetrating oil, buy a spray can and try to spray them over a period of a few days, since you can't soak them you will have to just spray them a few times... over a few days..