Bill,

So history tells us the original composite LIM gaskets are probably leaking too huh? I can't argue this one ( not that I would want to) I guess I'll go pull the altenator and pull the LIM. I've already got the brake cleaner going. The top part of the LIM has more shine than the silverware

Injector question....do I need to label these as to which cylinder thay came out of? I seem to remember hearing something about that somewhere. Anything I need to do to the injectors ? I've been pretty good about putting injector cleaner through every now and then.

Thanks again... (you too Will)

Absolutely change the LIM gaskets while you're in there. You might also want to consider ditching the DEXcool, but there'* still some debate on that. Plenty of topics if you search for the keyword DEX.

You can mix up the injectors all you want. Won't make any difference.

Don't waste your money on injector cleaner more than once a year. Modern detergents in our gas are more than capable of keeping them clean. I've seen dozens of dozens of 3800 injectors. I RARELY see one that would have benfited from injector cleaner. (They either work great, or don't at all).

Here'* the step-by-step I put together for myself for replacing UIM and LIM gaskets. The torque specs are from the 1998 FSM (where torque specs were given!), but please double check in the Techinfo section. The nut and bolt sizes are from memory (so some still need to be filled in).

I estimate 8-12 hours if you've never done it before, half that if you have.

(Note: this procedure was performed on a 1998 Olds 88 L36 engine, but should be virtually identical for you)

==================================

PARTS/TOOLS LIST

LIM gasket set, GM 89017816
http://www.rmsautoparts.com/proddeta...?prod=89017816
(Or can be obtained through ZZP or at GM dealer; this is the newest style, aluminum framed set)

Thermostat, STANT 45848 (180°) or 45849 (195°)
Thermostat seal, STANT 25273
Thermostat gasket, FELPRO 35595
Radiator cap, STANT 10331
Injector seal kit, AC Delco 2171379
Oil filter, AC Delco PF47
http://www.rockauto.com/
(Discount codes easy to find, or all these items can be gotten at local auto parts store and/or GM dealer)

APN UIM kit
http://www.automotivepartsnetwork.co...product=229679
(Easily your best bet in a UIM, as it includes UIM and TB gaskets, reduced-diameter EGR stovepipe, and steel-sleeved EGR passage)

From your local auto parts store, get:
“Help” GM coolant elbow 2-pack (use the one with two orange o-rings)
Permatex “Surface Intensive” Blue medium strength threadlocker
Permatex Ultra Copper RTV
5 qts 10w30
2 gal Prestone “Extended Life” coolant
Brake cleaner and carb cleaner

Tools needed:
Socket set
Wrenches
Screwdrivers
Torque wrenches (good ranges are 25-250 in-lb and 20-200 ft lb)
Breaker bar and/or long pipe (for removing alternator!)
Something to scrape and clean gasket mating surfaces
Ramps or jackstands and chocks
Rags...lots and lots of rags

==================================

PROCEDURE TO REMOVE UIM AND LIM TO REPLACE LIM AND UIM GASKETS

Jack up
-Place front of vehicle on jack stands; chock rear wheels (Jack, stands, chocks)

Drain coolant
-Remove air dam (10mm socket)
-Remove rad cap
-Detach lower coolant hose; catch drainage in bucket; rock car to get more (Lg flat, bucket)
-Remove engine cover
-Remove thermostat housing and thermostat (10mm)
-Flush block with hose until water runs clear
-Remove harness, heat shield and front Knock Sensor; catch drainage (??mm, bucket)
-Replace Knock Sensor (??mm, 14 ft lb) and shield (??mm, ??? ft lb), and reattch knock sensor harness
-Reattach lower coolant hose (Lg flat)
-Replace air dam (10mm socket, ??? ft lb)

Drain oil
-Remove drain bolt and drain oil pan; catch oil in bucket (14mm, bucket)
-Remove filter and catch oil (bucket)
-Replace filter (AC Delco PF47)
-Replace drain bolt (14mm, 22 ft lb)

Jack down
-Put vehicle down off jack stands (jack)

Prep for UIM/LIM removal
-Remove battery (8mm and 1/2")
-Remove spark plug wires and boot heat shields from rear cylinders (2,4,6)
-Remove serpentine belt from alternator by rotating breaker c-cwise to remove tension (15mm socket, breaker)
-Remove alternator support brace (??mm)
-Remove alternator mounting bolts (??mm)
-Remove alternator output nut and electrical connector (??mm)
-Remove alternator
-Disconnect MAP sensor harness from UIM
-Disconnect IAT sensor harness from bellows
-Remove airbox and bellows (Flat and phillips)
-Disconnect MAF, TPS and IAC sensor harnesses from TB
-Disconnect coolant temperature sensor from LIM
-Disconnect EGR harness from EGR valve
-Remove vacuum lines from TB and FPR
-Remove EVAP solenoid from bracket; move solenoid assembly out of the way (Flat)
-Remove accessory and brake booster vacuum lines from UIM
-Remove fuel rail nuts (10mm)
-Remove injector wire connectors from injectors
-Remove fuel rail and tie up out of the way (Strap)
-Remove exhaust crossover--optional if have 8/10mm ratchet wrench to reach TB support bracket (??mm)
-Remove CC and throttle cables from TB and bracket
-Remove TB support bracket (10mm)
-Remove TB (10mm)

Remove UIM
-Remove EGR heat shield (??mm)
-Move bundled harness(es) (IAT/MAF/TPS/IAC/EGR/injectors) out of the way
-Remove UIM bolts; remove UIM (8mm)

Remove LIM
-Remove remaining alternator bracketing from rear part of LIM (??mm)
-Remove EVAP solenoid bracket from front part of LIM (??mm)
-Remove EGR tube from LIM (10mm)
-Remove LIM bolts; remove LIM…coolant bypass elbow will break off (10mm)

Clean and prep block
-Stuff rags into all head ports, and place rag over lifter valley
-Pick broken coolant elbow bit out of tensioner (Flat)
-Remove old LIM gaskets and side seals from block; scrape area, clean with solvent, and buff (use your favorite method)

(Now is a good time to inspect belt, hoses, and wiring harnesses)
(Also a good time to change plugs)
(Also a good time to change injector o-rings)
(Also a good time to inspect the valve cover gaskets for leakage)
(Also a good time to degrease the "hard-to-reach" parts of the block and tranny cover)

Clean and prep LIM
-Soak LIM bolts in solvent and wirebush threads
-Remove ECT sensor from LIM, being careful not to break plastic fitting (??mm)
-Pick broken coolant elbow bit out of LIM (flat)
-Remove stovepipe if replacing with Buttermore pipe or other aftermarket pipe (socket to fit inside, vise grips)
-Remove front coolant cap from LIM (10mm)
-Scrape away gunk from sealing surfaces, clean LIM with degreaser/solvent, and buff (again, use your favorite method)
-Examine LIM carefully for cracks, bad pitting and warpage (straightedge, magnifying glass)
-Replace front coolant cap with new gasket (10mm, 15 ft lb)
-Replace ECT sensor with thread sealer (??, 18 ft lb)
-Install stovepipe if replacing (hammer, woodblock)

Clean and prep UIM (if re-using)
-Soak UIM bolts in solvent and wirebrush threads
-Remove MAP sensor and PCV valve housing cover
-Remove vacuum fitting
-Clean inside UIM and runners with generous amounts of solvent/degreaser---it will be nasty
-Remove runner insert; inspect for cracks/damage
-Examine UIM carefully for cracks/breakage, especially in EGR area (small pick, magnifying glass)
-Remove and discard main gasket, TB gasket, PCV o-ring, PCV valve, and vacuum fitting o-ring/seal

Clean and prep TB
-Remove MAF sensor from TB (?? torx or SMALL vise grips)
-Clean out TB and MAF screen with carb cleaner and a toothbrush
-Clean MAF filament with a q-tip and rubbing alcohol
-Replace MAF in TB (?? torx or SMALL vise grips, ?? in lb)

Replace LIM
-Remove rags from valley and head ports
-Place coolant bypass elbow into tensioner hole until seated (lube with anti-freeze if needed)
-Lay new LIM gaskets and new end seals in place; dab RTV in corners
-Lay down LIM, ensuring that bypass elbow seats fully in LIM and bolt holes and gaskets line up
-Place bolts and hand tighten (use blue threadlocker)
-Torque bolts, crosswise pattern, center to ends (10mm, 11 ft lb)
-Replace EGR tube into LIM (use blue threadlocker) (10mm, 21 ft lb)
-Replace EVAP solenoid bracket (use blue threadlocker) (??mm, 22 ft lb)
-Replace alternator bracketing (use blue threadlocker), ensuring fat wire harness goes under the armature (??mm, 22 ft lb)

Replace UIM
-Install new PCV valve and PCV housing o-ring
-Replace PCV housing cover and MAP sensor
-Replace vacuum fitting, using new o-ring/seal
-Install new TB gasket
-Insert runners into UIM
-Install new main gasket, ensuring J-tube hooked end points away from TB inlet
-Lay down UIM, ensuring EGR tube goes through hole in UIM and bolt holes line up
-Place bolts and hand tighten (use blue threadlocker)
-Torque bolts, crosswise pattern center to ends (8mm sock, 89 in lb)
-Reattach EGR heat shield (??mm, 12 ft lb)

Replace TB
-Replace TB on studs (use blue threadlocker on nuts; use red on rear nuts if studs are loose)
-Replace TB support bracket (use blue threadlocker, 10mm, 89 in lb)
-Reattach CC and throttle cables to TB and bracket

Replace other items
-Install new plugs, if changing (use anti-sieze compound, 20 ft lb)
-Reattach exhaust crossover, if removed (use anti-sieze compound, ??mm, 15 ft lb)
-Bring fuel rail down and attach harness connectors
-Install fuel rail, ensuring injectors are well-seated in LIM
-Replace fuel rail nuts and torque (use blue threadlocker, 10mm, 89 in lb)
-Reattach accessory and brake booster vacuum lines on UIM
-Reattach EVAP solenoid on bracket
-Reattach vacuum lines to TB and FPR
-Reattach EGR harness to EGR valve
-Reconnect temperature sensor on LIM
-Reconnect MAF, TPS and IAC sensor harnesses on TB
-Replace airbox and bellows (flat and phillips)
-Reconnect IAT sensor harness on bellows
-Reconnect MAP sensor harness on UIM
-Make sure all harness wiring is properly re-loomed and re-anchored
-Reattach alternator bolts (use anti-sieze, ??mm, 37 ft lb)
-Reattach alternator contact (??mm, 15 ft lb)
-Reattach alternator bracket (use blue threadlocker, ??mm, 15 ft lb)
-Replace serpentine belt onto alternator pulley (15mm socket, breaker)
-Replace spark plug wires (use anti-moisture compound) with boot heat shields (use vaseline or similar)
-Replace battery (use anti-moisture compound, 8mm , 1/2")
-Refill coolant
-Install new thermostat with new seal and new gasket (use blue threadlocker, 10mm, 20 ft lb)
-Install new radiator cap

Drain oil
-Remove drain bolt and drain oil pan; catch oil in bucket (14mm, bucket)
-Remove filter and catch oil (bucket)
-Replace filter (AC Delco PF47)
-Replace drain bolt (14mm, 22 ft lb)
-Refill oil

Jack down
-Put vehicle down off jack stands (jack)

Checks
Start engine and allow to warm up; meanwhile:
-Check for coolant leaks at hoses, rad cap, bypass elbow, t-stat housing, LIM endcap, LIM gaskets, UIM gasket, TB gasket
-Check for oil leaks at filter and drain plug, LIM gaskets and LIM endcaps
-Test for vacuum leaks at all vacuum hoses and connections, PCV housing, TB-UIM, UIM-LIM and LIM-head interfaces
-Look for exhaust leaks at both ends of crossover pipe
-Watch for CEL codes

Replace engine cover

Test drive, then check everything again

Thanks Will. I just printed the upper intake failure info that has all the part numbers on it. I'll run into town and get the gaskets and coolant elbow etc.

I forgot to mention that this is the SECOND UIM failure. When I bought the car with 77,000 on it, I flushed the dexcool and put in fresh (dexcool) coolant. Thats when I noticed it leaking under the TB. I took it in to a local shop. $675 later the UIM was replaced. Back then it was a $350 dollar part. When the shop repaired it, they put ethylene in it. So it'* had green it in for 4 or 5 years now. I'll be putting the EG in it.

When I pulled the UIM yesterday the EGR stove pipe was actually setting down in the LIM under coolant. The hole in the UIM where the stove pipe comes through is eaten away pretty good.

All I have in the way of Torque wrenches is a 1/2 inch. I just bought it to work on the Beemer. It'* a craftsman. With the twist handle to dial it in. Will I need a 3/8 inch for the UIM install ? Thats 11 ft lbs right ?

agrazela,

WOW is the word that comes to mind. Thanks for the list. Got it printed out. I'm not sure what some of this stuff is, but I'll ask when I get to that point. I need to finish the teardown and order parts. Hopefully I can do that today. Not sure.

I'll check in with you guys later with an update. Thanks again everybody.

that'* around 11 ft lbs. (from memory) but the upper is around 8.

There is a metal L26 upper listed in the for sale section. Mmmm metal

the most important think to do on a series2 is the LIM gasket that there major problem


im not sure if for performance the metal upper is better whit the sleeve plastic upper i think that the best fix

Not to steal the thread here or anything.. but are the felpro second design gaskets (MS958091) any good? I ended up buying it from rock auto... so I hope it flies lol.

I don't want to hijack either but I am wondering the same question. I missed the metal lower suggestion and traded an amp for the Fel Pro ones from a friend that worked at Checkers when I did mine back in July. Am I gonna have to tear both cars apart again in a month? How long will they last?

I had the EXACT same problem happen to mine. Hydrolocked the motor due to an UIM failure. I shut the car off, and it wouldnt even crank over after that. Pulled the plugs and coolant shot out. I replaced the UIM, LIM gaskets, and had the heads redone. It rans awsome for about 70 miles then developed a rod knock which scored my crank. I had to rebuilt the entire motor after that. Kinda sucked. So, I would suggest that you pull the oil pan off and throughly flush lots of oil through the motor. It wouldnt even hurt to pull the rod caps off and check the bearings. All mine were good except #1. They had to take .010" off the crank from that. Just trying to help you avoid the same costly disaster that I ended in.