GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 471
Most of the cleaning process can
be carried out with common hand tools and
readily available solvents or soluti ons. Carbon deposits can be chipped away
using a hammer and a hard wooden chisel. Old gasket material and varnish or
sludge can usually be re moved using a scraper and/ or cleaning solvent.
Extremely stubborn deposits may require the use of a power drill with a wire
brush. If using a wire brush, use extrem e care around any critical machined
surfaces (such as the gasket surfaces, bearing saddles, cylinder bores, etc.).
Use of a wire brush is NOT RECO MMENDED on any aluminum components.
Always follow any safety recommendations given by the manufacturer of the
tool and/or solvent. You s hould always wear eye prot ection during any cleaning
process involving scraping, chipping or spraying of solvents.
An alternative to the mess and hassle of cl eaning the parts yourself is to drop
them off at a local garage or machine shop. They will, more than likely, have the
necessary equipment to properly clean all of the parts for a nominal fee.
CAUTION - Always wear eye protection duri ng any cleaning process involving
scraping, chipping or spraying of solvents.
Fig. 2: Use a ring expander tool to remove the piston rings
Remove any oil galley plugs, freeze pl ugs and/or pressed-in bearings and
carefully wash and degrease all of the engine components including the
fasteners and bolts. Small par ts such as the valves, springs, etc., should be
placed in a metal basket and allowed to soak. Use pipe cleaner type brushes,
and clean all passageways in the co mponents. Use a ring expander and
remove the rings from the pistons. Cl ean the piston ring grooves with a special
tool or a piece of broken ri ng. Scrape the carbon off of the top of the piston. You
should never use a wire brush on the pist ons. After preparing all of the piston
assemblies in this manner, wash and degrease them again.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 474
Fig. 7: Drill out the damaged threads with t he specified size bit. Be sure to drill
completely through the hole or to the bottom of a blind hole
Fig. 8: Using the kit, tap the hole in or der to receive the thread insert. Keep the
tap well oiled and back it out frequently to avoid clogging the threads
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 475
Fig. 9: Screw the insert onto the inst aller tool until the tang engages the slot.
Thread the insert into the hole until it is 1/4-1/2 turn below the top surface, then
remove the tool and break off the tang using a punch
Several methods of repairi ng damaged threads are availa ble. Heli-Coil® (shown
here), Keenserts® and Microdot® are among the most widely used. All involve
basically the same principl e - drilling out stripped thread s, tapping the hole and
installing a prewound insert - making we lding, plugging and oversize fasteners
unnecessary.
Two types of thread repair inserts are us ually supplied: a standard type for most
inch coarse, inch fine, metric course and metric fine thread sizes and a spark
lug type to fit most spark plug port si zes. Consult the individual tool
manufacturer's catalog to determine exac t applications. Typical thread repair
kits will contain a selection of prewoun d threaded inserts, a tap (corresponding
to the outside diameter thr eads of the insert) and an installation tool. Spark plug
inserts usually differ because they requi re a tap equipped with pilot threads and
a combined reamer/tap section. Most ma nufacturers also supply blister-packed
thread repair inserts separately in addition to a master kit containing a variety of
taps and inserts plus installation tools.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 476
Before attempting to repair a threaded
hole, remove any snapped, broken or
damaged bolts or studs. Penetrating oil ca n be used to free frozen threads. The
offending item can usually be removed with locking pliers or using a screw/stud
extractor. After the hole is clear, the thread can be repaired, as shown in the
series of accompanying illustrations and in the kit manufacturer's instructions.
ENGINE PREPARATION
To properly rebuild an engine, you must fi rst remove it from the vehicle, then
disassemble and diagnose it. Ideally you should place your engine on an engine
stand. This affords you the best access to the engine components. Follow the
manufacturer's directions for using the stand with your particular engine.
Remove the flywheel or fl explate before installing the engine to the stand.
Now that you have the engine on a stand, and assuming that you have drained
the oil and coolant from the engine, it's ti me to strip it of all but the necessary
components. Before you start disassembli ng the engine, you may want to take
a moment to draw some pictures, or fabr icate some labels or containers to mark
the locations of various components and the bolts and/or studs which fasten
them. Modern day engines use a lot of littl e brackets and clips which hold wiring
harnesses and such, and these holders are often mounted on studs and/or bolts
that can be easily mixed up. The manufacturer spent a lot of time and money
designing your vehicle, and they wouldn't have wasted any of it by haphazardly
placing brackets, clips or fasteners on t he vehicle. If it's present when you
disassemble it, put it back when you asse mble, you will regret not remembering
that little bracket which holds a wire har ness out of the path of a rotating part.
You should begin by unbolting any accessories still attached to the engine, such
as the water pump, power steering pump, alternator, etc. Then, unfasten any
manifolds (intake or exhaust) which were not removed during the engine
removal procedure. Finally, remove any covers remaining on the engine such
as the rocker arm, front or timing cove r and oil pan. Some front covers may
require the vibration dam per and/or crank pulley to be removed beforehand.
The idea is to reduce the engine to the bar e necessities (cylinder head(s), valve
train, engine block, crankshaft, pistons and connecting rods), plus any other 'in
block' components such as oil pumps, balance shafts and auxiliary shafts.
Finally, remove the cylinder head(s) from the engine block and carefully place
on a bench. Disassembly instructions fo r each component follow later in this
section.
CYLINDER HEAD
There are two basic types of cylinder heads used on today’s automobiles:
the Overhead Valve (OHV) and the Over head Camshaft (OHC). The latter can
also be broken down into two subgr oups: the Single Overhead Camshaft
(SOHC) and the Dual Overhead Camshaft (DO HC). Generally, if there is only a
single camshaft on a head, it is just referred to as an OHC head. Also, an
engine with a OHV cylinder head is also known as a pushrod engine.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 477
Most cylinder heads these days are made of
an aluminum alloy due to its light
weight, durability and heat transfer qualit ies. However, cast iron was the
material of choice in the past, and is st ill used on many vehicles today. Whether
made from aluminum or iron, all cylinder heads hav e valves and seats. Some
use two valves per cylinder, while the more hi-tech engines will utilize a multi-
valve configuration using 3, 4 and
even 5 valves per cylinder. When the va lve contacts the seat, it does so on
precision machined surfaces, which seal s the combustion chamber. All cylinder
heads have a valve guide for each valve. The guide centers the valve to the
seat and allows it to move up and down within it. The clearance between the
valve and guide can be critical. Too much clearance and the engine may
consume oil, lose vacuum and/or damage the seat. Too little, and the valve can
stick in the guide causing t he engine to run poorly if at all, and possibly causing
severe damage. The last component all cylinder heads have are valve springs.
The spring holds the valve against its s eat. It also returns the valve to this
position when the valve has been opened by the valve train or camshaft. The
spring is fastened to the valve by a retainer and valve locks (sometime\
s called
keepers). Aluminum heads will also have a valve spring shim to keep the spring
from wearing away the aluminum.
An ideal method of rebuilding the cylin der head would involve replacing all of
the valves, guides, seats, springs, et c. with new ones. However, depending on
how the engine was maintained, often this is not necessary. A major cause of
valve, guide and seat wear is an improperly tuned engine. An engine that is
running too rich, will often wash the lubric ating oil out of the guide with gasoline,
causing it to wear rapidly. Conversely, an engine which is running too lean will
place higher combustion temperatures on the valves and seats allowing them to
wear or even burn. Springs fall victim to the driving habits of the individual. A
driver who often runs the engine rpm to the redline will wear out or break the
springs faster then one that stays well below it. Unfortunately, mileage takes it
toll on all of the parts. G enerally, the valves, guides, springs and seats in a
cylinder head can be machined and re-used, saving you money. However, if a
valve is burnt, it may be wise to replace all of the valves, since they were all
operating in the same environment. The same goes for any other component\
on
the cylinder head. Think of it as an insurance policy against future problems
related to that component.
Unfortunately, the only way to find out wh ich components need replacing, is to
disassemble and carefully check each piece. After the cylinder head(s) are
disassembled, thoroughly clean all of the components.
DISASSEMBLY
Before disassembling the cylinder head, you may want to fabricate some
containers to hold the various parts, as some of them can be quite small (such
as keepers) and easily lost. Also keeping yourself and the components
organized will aid in assembly and reduce confusion. Where possible, try to
maintain a components original location; th is is especially important if there is
not going to be any machine work performed on the components.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 485
CYLINDER HEAD
There are several things to check on
the cylinder head: valve guides, seats,
cylinder head surface flatness, cracks and physical damage.
VALVE GUIDES
Now that you know the valves are good, you can use them to check the guides,
although a new valve, if available, is preferred. Before you measure anything,
look at the guides carefully and inspect t hem for any cracks, chips or breakage.
Also if the guide is a removable style (a s in most aluminum heads), check them
for any looseness or evidence of movem ent. All of the guides should appear to
be at the same height from the spring s eat. If any seem lower (or higher) from
another, the guide has moved. Mount a dial indicator onto the spring side of the
cylinder head. Lightly oil the valve stem and insert it into the cylinder head.
Position the dial indicator against the valve stem near the tip and zero the
gauge. Grasp the valve stem and wiggle towards and away from the dial
indicator and observe the readings. Mount the dial indicator 90 degrees from
the initial point and zero the gauge and again take a reading. Compare the two
readings for a out of round condition. Check the readings against the
specifications given. An Inside Diamete r (I.D.) gauge designed for valve guides
will give you an accurate valve guide bore measurement. If the I.D. gauge is
used, compare the readings wit h the specifications given. Any guides that fail
these inspections should be replaced or machined.
Fig. 11: A dial gauge may be used to che ck valve stem-to-guide clearance; read
the gauge while moving the valve stem
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 489
There is no repair or refinishing possi
ble with the springs, retainers and valve
locks. If they are found to be worn or defective, they must be replaced with new
(or known good) parts.
CYLINDER HEAD
Most refinishing procedures dealing wit h the cylinder head must be performed
by a machine shop. Read the informati on below and review your inspection
data to determine whether or not machining is necessary.
VALVE GUIDE
If any machining or replacements are made to the valve guides, the seats must
be machined.
Unless the valve guides need machining or replacing, the only service to\
perform is to thoroughly clean them of any dirt or oil residue.
There are only two types of valve gu ides used on automobile engines: the
replaceable-type (all alumi num heads) and the cast-in in tegral-type (most cast
iron heads). There are four recommended methods for repairing worn guides.
• Knurling
• Inserts
• Reaming oversize
• Replacing
Knurling is a process in which metal is displaced and raised, thereby reducing
clearance, giving a true center, and providing oil control. It is the least
expensive way of repairing the valve guides . However, it is not necessarily the
best, and in some cases, a knurled valve guide will not stand up for more than a
short time. It requires a special knurle r and precision reaming tools to obtain
proper clearances. It would not be cost effective to purchase these tools, unless
you plan on rebuilding several of the same cylinder head.
Installing a guide insert involves machin ing the guide to accept a bronze insert.
One style is the coil-type wh ich is installed into a threaded guide. Another is the
thin-walled insert where the guide is ream ed oversize to accept a split-sleeve
insert. After the insert is installed, a s pecial tool is then run through the guide to
expand the insert, locking it to the guide. The insert is then reamed to the
standard size for proper valve clearance.
Reaming for oversize valves restores normal clearances and provides a true
valve seat. Most cast-in type guides can be reamed to accept an valve wi\
th an
oversize stem. The cost factor for this can become quite high as you will need
to purchase the reamer and new, oversize stem valves for all guides which
were reamed. Oversizes ar e generally 0.003 to 0.030 in. (0.076 to 0.762mm),
with 0.015 in. (0.381mm) being the most common.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 491
The first step for any assembly job is
to have a clean area in which to work.
Next, thoroughly clean all of the parts and components that are to be
assembled. Finally, place all of the co mponents onto a suitable work space and,
if necessary, arrange the parts to their respective positions.
1. Lightly lubricate the valve stems and insert all of the valves into the
cylinder head. If possible, maintain their original locations.
2. If equipped, install any valve spring shims which were removed.
3. If equipped, install the new valve seal s, keeping the following in mind:
• If the valve seal presses over the guide, lightly lubricate the outer
guide surfaces.
• If the seal is an O-ring type, it is installed just after compressing
the spring but before the valve locks.
4. Place the valve spring and retainer over the stem.
5. Position the spring compressor tool and compress the spring.
6. Assemble the valv e locks to the stem.
7. Relieve the spring pressure slowly and insure that neither valve lock
becomes dislodged by the retainer.
8. Remove the spring compressor tool.
9. Repeat Steps 2 through 8 until all of the springs have been installed.
ENGINE BLOCK
GENERAL INFORMATION
A thorough overhaul or rebuild of an engine block would include replacing the
pistons, rings, bearings, timing belt/chai n assembly and oil pump. For OHV
engines also include a new camshaft and lifters. The block would then have the
cylinders bored and honed oversize (or if using removable cylinder sleeves,
new sleeves installed) and the cranksha ft would be cut undersize to provide
new wearing surfaces and per fect clearances. However, your particular engine
may not have everything worn out. What if only the piston rings have worn out
and the clearances on everything else are still within factory specifications?
Well, you could just replace the rings and put it back together, but this would be
a very rare example. Chances are, if one component in your engine is worn,
other components are sure to follow, and soon. At the very least, you should
always replace the rings, bearings and oil pump. This is what is commonly
called a "freshen up".
CYLINDER RIDGE REMOVAL
Because the top piston ring does not travel to the very top of the cylinder, a
ridge is built up between the end of the trav el and the top of the cylinder bore.
Pushing the piston and connecting rod assembly past the ridge can be difficult,
and damage to the piston ring lands could occur. If the ridge is not removed
before installing a new piston or not re moved at all, piston ring breakage and
piston damage may occur.