scratch engine #2

[slimfatboy]

is there something wrong with the sII 3800 bottom end, maybe bearing issues? i get to replace the engine the second time around for what sounds to be the same thing. i went fishing over the weekend and started it up sunday to head back home(sat from friday night) and it knocked briefly. i figured id idle for a moment and let pressure build up and carry on. which i did for aobut three miles when something caught my ear. i turned off the radio and ever once in a while i'd hear a metal/metal 'tink'. i pulled over to listen to it and look around. within minutes it started knocking louder and exponentially faster with some screaching noise. i assume a bearing slowly took a dump on me which gave it room to smack the valves on the up stroke. when i called around for a new replacement the boneyard owner said that he always suggests the replacement of the intake gasket. can anyone else validate that? his reasoning was that they go bad and leak antifreeze down to the bearings.

[richtazz]

It's actually an upper intake problem that leads to coolant in the oil and subsequent lower end failure if not caught in time. GM suggests changing the lower intake gaskets at the same time to alleviate any possilbe problem. The actual issue is an EGR passage that deteriorates in teh plastic upper plenum and causes the coolant paseges through the throttle body to crack and leak into the upper intake. If not caught in time, the coolant washes out the bearings and engine goes boom. The factory and aftermarket replacement upper plenums address this issue with a re-design and reinforcement of the problem area so it won't happen again.

[slimfatboy]

well that certainly stinks. part distributors or part no's maybe for the plenum and gasket? i see autozone has the gasket for 40 and 54 but no plenum available. Thanks

[BNaylor]

01-06-01-007A
Engine/Propulsion System
July, 2001


Subject: Engine Coolant Consumption or Coolant Leak (Inspect For Material Degradation/Replace Intake Manifolds)

Models: 1995-1997 Buick Riviera, 1995-1998 Buick LeSabre, Park Avenue, 1996-1998 Buick Regal, 1998 Chevrolet Lumina, Monte Carlo, 1995-1996 Oldsmobile Ninety-Eight, 1995-1998 Oldsmobile Eighty-Eight, 1998 Oldsmobile Intrigue, 1995-1998 Pontiac Bonneville, 1997-1998 Pontiac Grand Prix, with 3.8L Engine (VIN K - RPO L36)


This bulletin is being revised to correct parts and labor operation usage. Please discard Corporate Bulletin Number 01-06-01-007 (Section 6 - Engine/Propulsion System).


Condition

Some owners may comment on excessive engine coolant consumption, or an engine coolant leak near or under the throttle body area of the upper intake manifold.


Cause

Upper intake manifold composite material may degrade around the EGR stove pipe and could result in an internal or external coolant leak.


Correction


Follow the upper intake manifold removal instructions found in the Engine Unit Repair Section of the Service Information Manual.
Refer to the arrow in the illustration of the upper intake manifold above. Inspect the inner diameter of the EGR passage for signs of material degradation. Degradation will appear as "pitting" of the composite material in the EGR port passage.
If degradation of upper intake manifold composite material is found, replace the lower and upper intake manifolds with the following part numbers:
Lower Intake - 24508923
Upper Intake - 17113136 (includes necessary upper intake plenum gaskets)
Lower Intake Gasket - 12537197
Follow the lower and upper intake manifold installation instructions found in the Engine Unit Repair Section of the appropriate Service Manual.
If degradation is not apparent, skip to Step 7.
Verify the repair.
If no degradation is found, evaluate the vehicle for other causes of excessive coolant consumption as noted in the Engine Diagnosis Section of the appropriate Service Manual.

Parts Information

Parts are currently available from GMSPO.


Warranty Information

For vehicles repaired under warranty, use the table as shown.







Thrasher CAI, DHP v1.0 PCM, SLP Headers,
3.25 SC pulley, CAIT GMAF, 2.5 DP/Hi-Flow CAT,
u-bend delete, 160 TS, ZZP Stage 1 72mm TB,
TB spacer, MSD 8.5mm wires, Autolite 103,
Goodyear Gatorback Serp. & SC Belt,
Nitto NT555R Drag Radials
1/4 ET: 13.210 sec. @ 104.490 mph
0 - 60 ft: 1.945 sec.

[richtazz]

Dorman makes the plenum (part #615-180), and they run about $130-$140 retail. We stock a Delphi (part# FH10095)that runs about $120, so they are available aftermarket.