butchc

Hi all,
Car is 88 IROC 305 TPI. After searching old posts and gathering information I have begun the work of replacing the manifold gaskets ( typical anti freeze leak in the corner) , replacing the fuel injectors ( Hot start issues due to leaking and using South Bay) and valve seals. What a PITA that passenger side valve cover was! but it is off. Have a few questions. Car has 70K miles, 100% stock and been well maintained. I am looking at the EGR valve which as you know is buried in the intake. Should i consider replacing it while I have it apart or are they trouble free and leave it alone? Anything else I should while up to my waist in it? . Id much rather do it now rather than have it apart again.
Thanks in advance!

GeneralDisorder

iTrader: (1)

Fuel pressure regulator.

Stainless allen bolts for runners, intake, etc

Bead blast the intake manifold mating surfaces - you will find a lot of pitting in the corners that causes these leaks. Fill with metal epoxy and block sand smooth.

GD

butchc

Noted and regulator on order, thanks

Tootie Pang

iTrader: (2)

Is there a way to check for the anti-freeze leak? I'd rather not go back into mine but I've never had it off though I am losing a little coolant regularly. Maybe just spray the area with carb cleaner and listen for RPMs?

butchc, I was in the same boat. Mine had 118,000 almost completely unmodified. Found that the timing chain set was really slack. Fixed a big time idle hunting problem. An easy way to check is to see if your base timing floats around at idle. That is the cam "flopping" on the slack chain under the valve spring pressure.

GeneralDisorder

iTrader: (1)

Yeah you probably have the pitted manifold syndrome on the rear coolant ports. Mine leaked there slowly and ran down the bell-housing area. It dries up and burns off before it hits the ground. Since the manifold is aluminium they take the brunt of the abuse and get all nasty around the cooling ports. You'll never get them to seal without removing all the aluminium oxide in the deep pitting and filling the area. I had about two sessions of filling and block sanding till I got the pitting filled and the mating surface flat. Been several years since I did that and still perfectly dry. No more coolant loss or smell.

And yeah - on these old small blocks - the timing chain is an every 60k event if you want it to run right and the timing to be solid. That's a totally different job though.

GD

butchc

Like GD mine leaks were easy to detect. Nothing ever hit the floor and nothing in the oil but the anti freeze smell was strong. Mine was leaking at both front corners.

Not going any deeper into the motor, I am too old to live bent over a fender, LOL

Tootie Pang

iTrader: (2)

Can that coolant also leak into the intake runners?

GeneralDisorder

iTrader: (1)

It could. And into the valley. Also head bolts can leak into intake runners.

GD