a how to on inspecting engine [Archive] - GrandAmGT.com Forum


View Full Version : a how to on inspecting engine

04-18-2010, 01:24 PM
I'm looking for a how to or advice when checking parts for wear? how to spec stuff, check for wear etc etc

And what to look for on valves and worn cylinders

and another question what should I use to clean engine parts inside and out without ruining anything...

04-18-2010, 01:47 PM
and does that maintence book you get from auto zone have directions on how to swap out the throttle cable that goes to peddle? I think i need to rip out dash

04-18-2010, 02:01 PM
For cleaning you cant beat this stuff. Itll strip off anything that it touches we use it at work to clean all kinds of goop off or our equipment.


For measuring valves for wear youll need a set of calipers like these (http://www.google.com/products?q=calipers&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&ei=YmXLS8PLM4ziNfGq_KYF&sa=X&oi=product_result_group&ct=title&resnum=3&ved=0CD0QrQQwAg) which will give you exact mm measurements for thickness.

04-18-2010, 04:37 PM
yeah i got one of those, anyone know where i can get measurements of everything

04-18-2010, 07:10 PM
Engine Mechanical Specifications


General Data

Engine Type
60 V-6

204 cu in

RPO (VIN Code)
LA1 (E)

92 mm
3.62 in

84 mm
3.31 in

Compression Ratio

Firing Order

Oil Pressure - Warm
103 kPa
15 psi @ 1100 RPM

Cylinder Bore

92.019-92.037 mm
3.6228-3.6235 in

Out Of Round Maximum
0.007 mm
0.0003 in

Taper -- Thrust Side Maximum
0.010 mm
0.0004 in


Diameter-Gaged on the skirt 13 mm (0.51 in) below the centerline of the piston pin bore
91.970-91.988 mm
3.6209-3.6216 in

0.032-0.068 mm
0.0013-0.0027 in

Pin Bore
23.006-23.013 mm
0.9057-0.9060 in

Piston Ring

Top Groove Side Clearance
0.04-0.075 mm
0.002-0.0033 in

Second Groove Side Clearance
0.04-0.09 mm
0.002-0.0035 in

Top Ring Gap
0.15-0.36 mm
0.006-0.014 in

Second Ring Gap
0.48-0.74 mm
0.0197-0.0280 in

Oil Ring Groove Clearance
0.48-0.20 mm
0.008 in

Gap with segment at 92.0 mm (3.62 in)
0.25-0.75 mm
0.0098-0.05 in

Piston Pin

22.9915-22.9964 mm
0.9052-0.9054 in

Clearance In Piston
0.0096-0.0215 mm
0.0004-0.0008 in

Fit In Rod
(-)0.0469-(-)0.017 mm press fit
0.0006-0.0018 in


Main Journal Diameter
67.239-67.257 mm
2.6473-2.6483 in

Main Journal Taper
0.005 mm
0.0002 in

Out Of Round - Max
0.005 mm
0.0002 in

Flange Runout - Max
0.04 mm
0.0016 in

Cylinder Block Main Bearing Bore Diameter
72.155-72.168 mm
2.8407-2.8412 in

Crankshaft Main Bearing Inside Diameter
67.289-67.316 mm
2.6492-2.6502 in

Main Bearing Clearance
0.019-0.064 mm
0.0008-0.0025 in

Main Thrust Bearing Clearance
0.032-0.077 mm
0.0012-0.0030 in

Crankshaft End Play
0.060-0.210 mm
0.0024-0.0083 in

Crankshaft Flange Runout - Max
0.04 mm
0.0016 in

Connecting Rod

Rod Bearing Journal Diameter
50.768-50.784 mm
1.9987-1.9994 in

Rod Bearing Journal Taper - Max
0.005 mm
0.0002 in

Rod Bearing Journal Out Of Round - Max
0.005 mm
0.0002 in

Rod Bearing Bore Diameter
53.962-53.984 mm
2.124-2.125 in

Rod Inside Bearing Diameter
50.812-50.850 mm
2.000-2.002 in

Rod Bearing Journal Clearance
0.018-0.062 mm
0.0007-0.0024 in

Rod Side Clearance
0.18-0.44 mm
0.007-0.017 in


Lobe Lift (Intake and Exhaust)
6.9263 mm
0.2727 in

Journal Diameter
47.45-47.48 mm
1.868-1.869 in

Camshaft Bearing Bore Diameter-Front and Rear
51.03-51.08 mm
2.009-2.011 in

Camshaft Bearing Bore Diameter-Middle #2 and #3
50.77-50.82 mm
1.999-2.001 in

Camshaft Bearing Inside Diameter
47.523-47.549 mm
1.871-1.872 in

Journal Clearance
0.026-0.101 mm
0.001-0.0039 in

Journal Runout - Max
0.025 mm
0.001 in

Valve System

Roller Lifter

Rocker Arm Ratio

Valve Face Angle

Seat Angle

Valve Seat Runout
0.050 mm
0.002 in

Seat Width-Intake
1.55-1.80 mm
0.061-0.071 in

Seat Width-Exhaust
1.70-2.0 mm
0.067-0.079 in

Valve Margin - Minimum Intake
2.10 mm
0.083 in

Valve Margin - Minimum Exhaust
2.70 mm
0.106 in

Valve Stem Clearance
0.026-0.068 mm
0.0010-0.0027 in

Valve Spring

Valve Springs Free Length
48.5 mm
1.89 in

Valve Springs Load (Closed)
320 N @ 43.2 mm
75 lb @ 1.701 in

Valve Springs Load (Open)
1036 N @ 32 mm
230 lb @ 1.260 in

Installed Height Intake-Exhaust
43.2 mm
1.701 in

Approx. # or coils

Oil Pump

Gear Lash
0.094-0.195 mm
0.0037-0.0077 in

Gear Pocket Depth
30.52-30.58 mm
1.202-1.204 in

Gear Pocket Diameter
38.176-38.226 mm
1.503-1.505 in

Oil Pump Gear

30.45-30.48 mm
1.199-1.200 in

38.05-38.10 mm
1.498-1.500 in

Side Clearance
0.038-0.088 mm
0.001-0.003 in

End Clearance
0.040-0.125 mm
0.002-0.005 in

Valve to Bore Clearance
0.038-0.089 mm
0.0015-0.0035 in

04-19-2010, 09:59 AM
thanks man, and i have a question putting LS6 springs in, I took the spring and slid the valve out, how do i get the other peice that holds the valve straight? is it pressed in there? because mine spring doesnt fit over it. I think I have the peice i need to swap that out.

04-19-2010, 10:27 AM
I think this is the guide actually... i have the seals and stuff. Do I need to get a new guide or how do I get the spring to fit?


04-19-2010, 03:23 PM
dont quote me but i believe them come out as well..and the new valve seals will go in their place. did you get a shim to go between the spring and the head?

04-19-2010, 03:24 PM
That is your factory seal which will need to be removed. They should just pull off.

04-19-2010, 03:34 PM
nick i got these from you...

Heres a better pic of what i was pointing too... they seem like they are pressed in...

http://sphotos.ak.fbcdn.net/hphotos-ak-ash1/hs454.ash1/24969_1354800403036_1622246024_856926_2818085_n.jp g

and heres what i got with springs

http://sphotos.ak.fbcdn.net/hphotos-ak-ash1/hs454.ash1/24969_1354800443037_1622246024_856927_3567640_n.jp g

04-19-2010, 06:47 PM
them are the stock 3400 valve seals, the should pull off with some pliers...youll need shims for the bottom of the spring because look how thw stock seal is built, the valve spring sits on the bottom section of it so it is NOT touching the head. it will tear the aluminum up.

04-19-2010, 08:49 PM
wait im confused,so i need a new seal? the nipple part is to wide at bottom for spring to sit on, and those 2 little peices is what i got with the springs

04-19-2010, 09:12 PM
those are the replacement valve seals youll be using, but you will need to get shims for under the spring...check around wottech and see if maybe theyre over there maybe?

04-20-2010, 09:47 AM
does the valve itself go through them

04-20-2010, 03:27 PM
yes sir, THAT seal, seals the valve stem so oil does not leak down into the combustion chamber

04-20-2010, 04:14 PM
nick i got these from you...

Heres a better pic of what i was pointing too... they seem like they are pressed in...

http://sphotos.ak.fbcdn.net/hphotos-ak-ash1/hs454.ash1/24969_1354800403036_1622246024_856926_2818085_n.jp g

and heres what i got with springs

http://sphotos.ak.fbcdn.net/hphotos-ak-ash1/hs454.ash1/24969_1354800443037_1622246024_856927_3567640_n.jp g

im following todds pictures but im trying to figure out how exactly the seals go in and which one goes first and his pictures he has an orange bottom

04-20-2010, 04:20 PM
like which is exhaust seals and which are the intake seals... he used ones that both look the same, both of mine look different, and do i put them on the valve or the valve guide

04-20-2010, 04:41 PM
and i have the peice that goes on top of spring that has the locking keys in it. what part do I need so the valve spring isnt touching aluminium head?

04-20-2010, 04:51 PM

04-20-2010, 05:36 PM
im not sure which are which, maybe theyre all the same?..i just threw mine on when i did my springs and havent had a problem with "mismatch" if there is a match..and yes, them seats are the ones youll need, i have them on my heads as well..you MIGHT havta grind em open a lil more to fit over the valve guide..well i did.

04-21-2010, 11:06 AM
does the seals go over the guide too just enough where the top of the seal is hanging off? and i only have 6 of black seals and 6 of grey ones.