C4 Engine removal/rebuild

[mjlisz]

Hi Folks,

I have a 1990 C4 with a standard L98 engine and 6 speed transmission. I discovered coolent in the oil pan awhile back and concluded that i must have blown a head gasket or similar. Not sure what happened there. I don't drive it hard at all and it only has 100,000 miles on it. Also,it looked like there was an oil leak somewhere on the upper part of the engine near the rear because there was always some oil dripping down the transmission bell housing. Not really dripping but you could tell that it was there. Anyway, I decided to tear down the engine and inspect/rebuild as needed. I have removed engines from 300Zx's quite a few times, but never a vette. I did a search on the forum and got a lot of usefull information. But I stil have a few questions I was hoping that someone who has done this before could assist with:

1) What to do with the A/C compressor/dryer canister. Can these just be moved out of the way or does it have to be removed?

2) How high does the car need to be off the ground in order to romove the engine with transmission? Removing them together seemed to be the preferred way. I have already removed the hood.

3) Does the radiator shroud need to come out? I have seen both ways mentioned. But I may be getting C3's and C4's mixed up. The A/C condensor looks like it has to stay in - unless I dissasembe the A/C lines. I really do not want to break the A/C lines.

4) I am also going to replace the clutch while everything is out. Several people mentioned to be sure to use a dual mass flywheel. Does the flywheel have to be replaced if I replace the clutch? Can it be resurfaced? These are expensive!

I was surprised that there were no engine removal procedure in the Chevy service manual which I bought for this purpose. Am I missing something?

Anything else that comes to mind will surely be appreciated.

Thanks in advance for all your help.

Mike

 

[Happydad]

Hi Folks,

I did a search on the forum and got a lot of usefull information. But I stil have a few questions I was hoping that someone who has done this before could assist with:

1) What to do with the A/C compressor/dryer canister. Can these just be moved out of the way or does it have to be removed?

2) How high does the car need to be off the ground in order to romove the engine with transmission? Removing them together seemed to be the preferred way. I have already removed the hood.

3) Does the radiator shroud need to come out? I have seen both ways mentioned. But I may be getting C3's and C4's mixed up. The A/C condensor looks like it has to stay in - unless I dissasembe the A/C lines. I really do not want to break the A/C lines.


I was surprised that there were no engine removal procedure in the Chevy service manual which I bought for this purpose. Am I missing something?

Anything else that comes to mind will surely be appreciated.

Thanks in advance for all your help.



Mike

Yes ..you can just move the AC away and not disconnect it
Yes .. you have to remove the Shroud but the radiator can stay

Jack stands should be fine to get under there to disconnect the trans stuff then just leave it on the stands..With the hood off there is a ton of room
Don't forget to remove the wiper motor,Distributer,all sensor wires on the sides of the block....This is how I did it on my 86..A 90 shouldn't be much different....Good Luck..Be Safe

 

[JAKE]

Folks do it different ways.

I've pulled and replaced the engine on my previously owner 86 Vette several times and last year I pulled and replaced the engine on my 96.

I never removed either the HOOD or the auto trans. I Pulled the engine from the side. To me, pulling the engine with the trans connected is a lot of unnecessary work, unless you need to work on the trans too.

I agree, the wiper motor should be removed to prevent it from being damaged. No need to disconnect, and thereby discharge the A/C. Just swivel everything out of the way.

The car only has to be high enough to allow you to crawl under, on your back to unbolt and rebolt parts such as trans, exhaust, etc.

Jake

 

[mjlisz]

Thanks for your help. I will be hard at it over the next several days. Anyone care to comment on whether or not you can resurface the flywheel?

Thanks,

Mike

 

[G Winter]

The flywheel has the springs in it instead of the clutch disc. It is a wear item. There are a couple specialty places that can resurface but I wouldn't and am going to replace my clutch and flywheel in the next three weeks.
lt4man provided this link for clutch parts and I plan on ordering from them.I have looked a number of places and this comes up with the best price.
http://www.carolinaclutch.com/ViewCart.aspx


Glenn

 

[geekinavette]

Folks do it different ways.

I've pulled and replaced the engine on my previously owner 86 Vette several times and last year I pulled and replaced the engine on my 96.

I never removed either the HOOD or the auto trans. I Pulled the engine from the side. To me, pulling the engine with the trans connected is a lot of unnecessary work, unless you need to work on the trans too.

I agree, the wiper motor should be removed to prevent it from being damaged. No need to disconnect, and thereby discharge the A/C. Just swivel everything out of the way.

The car only has to be high enough to allow you to crawl under, on your back to unbolt and rebolt parts such as trans, exhaust, etc.

Jake

That is exactly how I did it with my 84...left the hood and trans in place and pulled the engine from the side.

 

[JAKE]

That is exactly how I did it with my 84...left the hood and trans in place and pulled the engine from the side.

Yep. Just have a look at my avatar and you'll see my new 388 going in.

Jake

 

[barryz]

Removing C4 hood

I've not removed a C4 hood before. What's involved?
Is it complicated?

Thanks
BarryZ
Reading PA

 

[vetteoz]

I've not removed a C4 hood before. What's involved?

Why?
Take the hood strut off , support hood with broom stick.
Undo the 4 hinge bolts.Will sit in place on the studs.Needs 2 people to life off .That is the easy part.
Getting it lined up correctly when you reinstall is a PITA which is why people leave it in place.

 

[vetteoz]

I am also going to replace the clutch while everything is out. Several people mentioned to be sure to use a dual mass flywheel. Does the flywheel have to be replaced if I replace the clutch? Can it be resurfaced? These are expensive!

The DM is not supposed to be resurfaced. You can convert to a single mass flywheel cheaper BUT you will get trans noise in neutral.(rocks in a can noise )

Info on putting ZF6 in 4 +3 car but theory the same
Yours is 1 pce RMS type

http://members.cisdi.com/~anesthes/zf6/
Singlemass ZF6, ZR1 pivot stud, snakeoil? - Corvette Forum
No need to remove the radiator shroud .The engine will hit the cross brace behind the radiator long before it comes anywhere near the shroud.

 

[Gary Bakka]

top bell housing bolts

The DM is not supposed to be resurfaced. You can convert to a single mass flywheel cheaper BUT you will get trans noise in neutral.(rocks in a can noise )

Info on putting ZF6 in 4 +3 car but theory the same
Yours is 1 pce RMS type

http://members.cisdi.com/~anesthes/zf6/
Singlemass ZF6, ZR1 pivot stud, snakeoil? - Corvette Forum
No need to remove the radiator shroud .The engine will hit the cross brace behind the radiator long before it comes anywhere near the shroud.

How do u get at top bell housing bolts .gbakka@sbcglobal.net

 

[DonB]

How do u get at top bell housing bolts .gbakka@sbcglobal.net

To initially break the top bell housing bolts, I broke them loose from the top after removing the distributor and o/p senders. You can only get about 1/8th a turn from the top with a long combination wrench. Then unscrewed them the rest of the way from underneath with 2 long extensions a ratchet and a swivel socket. You can just barely see them, but it'll work. You will need at least 30" of extension.

Also to the poster who asked, "how high to get the car?" Get it up as high as you can. It'll make re-assembly all the easier.


ANOTHER TIP: While the engine is out, it is a good time to inspect/replace any of the power steering lines and hoses for the Rack & Pinion steering. It's also a good time to repair wire harnesses, because most of these things are buried when the engine is "in."