Replacing LT1 Head Gaskets

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Jan 31, 2018 | 05:52 AM

nodnarb481

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From: Conshohocken, PA

Replacing LT1 Head Gaskets

I've been having some white smoke issues coming out the tail pipe lately so I'm thinking it would be wise to dig in and take care of the head gaskets. I haven't had any overheating issues lately. I did have some years ago but never had any issues until recently. I read through a bunch of threads to gather most of the information I need but I was hoping to get a few more questions answered before digging in.

Parts list:
Felpro gasket set: HS9966PT
ARP Head Bolts: 134 - 3601
Coolant: I assume I'll be draining, refilling, bleeding for this.
Oil/Filter: I assume I'll be draining and refilling for this.
I've got a shop lined up to take a look at the heads and fix them if they're warped.
I may replace the steam pipe in the back if it is as big of a pain as everyone says it is.
Anything else I'm missing?

Couple other questions:
I'm doing this in my driveway. Let's say worst case scenario, I take the heads off, the shop needs to work on them. I work during the week so the car has to sit for a week. How should I cover everything up from the elements?

Anything special with changing the oil? I'm not putting in anything new so do I have to break it in with a few oil changes?

Any other important tidbits for the gaskets/head bolts/cleaning off old gasket?

Jan 31, 2018 | 07:17 AM

biketopia

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Take your time, pictures and label everything you remove. Good torque wrench, http://shbox.com/1/4th_gen_tech1.html has a ton of torque specs and how to write ups. Once you get the heads off, stuff some rags or paper towels in the bores and valley to keep debris out while you clean the gasket surfaces, dont forget to remove them, seen it happen getting in a hurry... Brake clean will be your friend to get every thing clean again after gasket removal. If it needs to stay apart a while wipe some oil on your fingers and run it around the cylinder bores or spray with wd40 or the like to keep from flash rusting, just clean it all off before final assembly. Keep it all covered once it's clean with tape and a towel or something of the sort. After it's all back together I like to drain the oil, fresh oil and filter, nothing fancy but an ok filter fire it up, get it up to temp, if all seems good drive it around the block and once your satisfied, drain the oil and change the filter to whatever flavor you normally use and call it good.

Jan 31, 2018 | 10:26 AM

96LT1Z

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From: Lincoln NE

^^ the shbox pages are great.
As for the steam pipe... I would plan on replacing it. When I did my heads the darn thing was clogged shut and getting it cleaned as a waste of time.. not to mention it probably would have broken in half. I ended up getting a couple brass fittings and rubber hose and replacing it that way. Not to mention how much easier that was to work with than the stupid steam pipe.
Good luck!

Jan 31, 2018 | 11:15 AM

SS RRR

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From: Jackstandican

Quote:

Originally Posted by nodnarb481

Couple other questions:
I'm doing this in my driveway. Let's say worst case scenario, I take the heads off, the shop needs to work on them. I work during the week so the car has to sit for a week. How should I cover everything up from the elements?

Shop towels in the oil valley and a garbage bag protruding over the edges of the block. Reason being is the cowl will not keep water out if with the hood closed and it will leak straight into the oil valley.
Check the heads to see if they're true and have them milled if they are not or you'll be facing the same issue if it is indeed a blown head gasket.

Jan 31, 2018 | 11:47 AM

ss.slp.ls1

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From: Orange County, CA

Good luck with the replacement. I had to change out cylinder heads due to a stripped sparkplug hole on the street in my cul de sac outside of my apartment. I had to work during the day so I spent 3 nights working on the car getting everything off and back together. It looks like you got some good advice from previous posters. Do as much research as you can. I had a book on hand as a reference, How to Rebuild Small Block Chevy LT-1/LT-4 Engines. The only thing I can think of off the top of my head to add is to unscrew the two drain plugs (one on each side) on the block to drain out all of the coolant before you attempt to remove the cylinder heads. Also, I would remove your oil pressure sensor before you have a chance to break it in the process. If I think of anything else I'll post it.

P.S. While you have the heads off and you are getting them trued to flat, I would have a valve job done on them.

Feb 3, 2018 | 07:31 AM

nodnarb481

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From: Conshohocken, PA

Thanks for the feedback guys. Got that book a couple weeks ago. Its a solid guide for sure. I'm gonna look into what parts everyone uses to replace the steam pipe and try to bundle that into my order.

Looks like all the parts are getting paid off with gift cards. Woo! Not as expensive as I thought this would be. Maybe I can still do my suspension this year after all.

Feb 12, 2018 | 06:04 PM

nodnarb481

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From: Conshohocken, PA

Quick question: is there any chance I'll need new push rods for this? I'm leaving everything stock but I wasn't sure if I might run into issues if I need to grind down the heads