LIM Gasket?

[daddyman]

Greetings,

I have been a lurker here for a while, soaking up the info and planning for some repairs. I have a small leak at the valve covers, and will be doing the vavle cover gaskets, and the plugs, wires, O2 sensor, PCV valve, when the weather gets a bit better, i.e. no hurricane.

So I had cleaned off the area around the covers to get a bit better idea about how the photos on the site matched up with what is on my car, etc. Drove off to work, etc. and later, while hooking up the battery tender, noticed a puddle of coolant on the top of the valve cover, and on the top of the engine block.

I am sure this is not good.

As the car is an SSEi, I will have to take the s/c off, then get the rest as described in the how-to's. But does the s/c have a gasket of some sort? I have not been able to find this info. The LIM gasket generally recommended seems to be the GM aluminum piece; anything else I should get while I am pulling the engine apart?

The wife is pretty understanding about vehicle maintenance, so I may be able to sneak a FWI and 3.6 pulley in while I am at it. Suggestions for other maintenance while doing this are appreciated.

Thanks for the assistance!

Happy trails,

Keith

[00Beast]

Yes the S/C has a gasket, you'll find it under "plenum gasket" on Rock Auto or at parts stores.

If you're doing the VC gaskets, LIM Gaskets and all that associated stuff, the only thing I can say is make sure the items on the maintenance list are all up to date. Supercharger oil, belts, new O2 sensors (most important yet neglected items ever), clean the TB, etc.

• 1987-2005 Bonneville / Buick 3800 Maintenance List
  
  Run Seafoam, Chevron Techron or Gumout Regane through gasoline every 5,000 miles.
  
  Grease: Ball Joints, Tie Rods Every 8-10k ( Green Grease or Amsoil Grease recommended)
  Air Filter Every 15k (Amsoil EaA, Purolator PureONE)
  PCV Valve Every 30k
  MAF Sensor Element Cleaning/TB Cleaning Every 50k viewtopic.php?f=48&t=1661
  Fuel Filter Every 15-25k (Purolator, AC Delco, WIX) http://www.pontiacbonnevilleclub.com/fo ... 45&t=23215
  Spark Plugs Every 30-50k (NGK TR55, AC Delco 41-101 or Autolite 605) (Never Bosch)
  Ignition Wires Every 30-50k (Napa Belden, AC Delco, Autolite Pro, NGK) (Never Taylor or Bosch)
  Oil & Filter Every 5-6k or Every 6 months (Valvoline SYNPower, Pennzoil Platinum, or Amsoil )(Mobil1, Purolator PureONE, Amsoil EaO, K&N or WIX) (Never Fram) viewtopic.php?f=45&t=214
  *Conventional Oil Every 3k/3 months(API SM/SN rating) (WIX (Napa), Delco or Purolator filter)
  Tires: Check Inflation Pressure & Visually Inspect Monthly Rotate Every 6-8,000 Miles
  Transmission Flush or Pan Drop Every 15-20k (Always make sure filter is changed when flushed) viewtopic.php?f=45&t=10193
  Cooling System Flush Every 25-50k or 3-5 Years (Peak or Prestone Mixes-With-Any Coolant Only) (Never Dexcool)
  Oxygen Sensor Every 80-100k (30k for non-heated) (AC Delco or Denso) (Absolutely never Bosch) viewtopic.php?f=48&t=794
  Accessory Belt Inspect every 15k, replace every 100k, or as needed
  Cabin Air Filter Inspect and Replace every 15k, or as needed in dusty conditions. (Note: 00+ Only) viewtopic.php?f=45&t=13626
  Evap Core Cleaning Whenever Needed (Note: 99 and older only) viewtopic.php?f=45&t=2432
  Brake Fluid Flush 3yr/50k
  Power Steering Fluid Replacement/Flush Every 100k or 5 years
  
  *Special Considerations*
  All Series II/III 3800's RPO's: L36, L26, L67 & L32, especially important on vehicles factory installed with orange Havoline Dexcool Antifreeze/Coolant: http://www.dex-cool.net/
  Lower Intake Manifold Gasket Replacement, every 80-100k (ignorance of this can allow coolant to enter your engine oil, this happening can cause irreversible lower engine damage, requiring replacement of subject engine)
  
  Series II, Naturally Aspirated, RPO:L36:
  Upper Intake Manifold Plenum Replacement, Every 80-100k (ignorance of this can allow coolant to enter your intake manifold, possible damage to occur can be hydrolock, irreversible damage to emissions devices, misfires, etc. Most times, engine replacement is required if ignored long enough.) viewtopic.php?f=53&t=1061
  
  Series I, II, III RPO Code L67 & L32:
  Change Supercharger Oil; Every 30-50k. (Intense Racing or GM Dealer) viewtopic.php?f=56&t=1690
  Supercharger Belt; Inspect Every 15k, Replace Every 100k or as needed.

8/28/2011 by 00Beast

[Archon]

Look at RockAuto under Fuel/Air for the plenum gasket. That's what you'll need for the supercharger. The Felpro set includes the two O-rings that you will need. Get a throttle body gasket. too. Remove and clean it while you have things apart.You'll also need the coolant elbows. You may also want to pick up some MAF cleaner.

[willwren]

While you're at it, seriously consider flushing out the DEX for good:

www.dex-cool.com

[daddyman]

Thanks for the advice to all.

Archon, the Felpro set with the o-rings to which you refer is the plenum gasket, correct? Thanks for the info about the elbows and the throttle body gasket.

00Beast, I have been working my was through the list and will take care of the MAF, throttle body clean, etc. when pulling the rest apart. (And maybe putting in the FWI. ) Thanks for the list.

Bill, I changed out the DexCool, about a year and a half ago after picking up the car. I have been using Old World (Peak) Final Charge, which is an OAT, but without the evil 2-eha.

I'll have to come up with a list of stuff to see if I am missing anything.

Happy trails,

Keith

[00Beast]

Here's my list from when I did mine: viewtopic.php?f=8&t=7838&p=80808&hilit= ... ket#p80808

[daddyman]

Planning question:

Would it be a bad idea to put the car on some ramps, with jacks, while doing this? It would make it easier to get to dropped parts, but would it be too difficult to pick out the intake manifold with it higher? About how much does the intake manifold weight?

Thanks again!

Happy trails,

Keith

[sonoma_zr2]

Stand on a plank across 2 stepstools or ladders. The intake is light, the supercharger weights more though, but it's not that heavy.

[00Beast]

I had it easy and had my car on the lift while doing it, but it is nice to have the car elevated. However, you do want to keep it level. If you have the means, I'd back the rear tires on the ramps and jack the front of the car up and use stands.

I recommend removing the supercharger and LIM separately. It's easier, less ackward and reduces the risk of spilling coolant into the engine. The S/C probably weighs 25 lbs and the LIM itself probably weighs 10 pounds, plus whatever coolant is in there.

[daddyman]

Well, the replacement project has begun. I spent the day slowly taking bits off, getting pictures to put it back together, and rereading the how-to's numerous times. With any luck, tomorrow the LIM itself will be removed.

Only one broken piece, which is the vacuum tree line thing that goes around from the BCA to the rear of the engine. Silly thing broke off on the passenger side junction to the LIM. Oh, well.

I'll try and get some photos up when I get the chance.

As an idea, on the s/c car, what two analog sensors would you find most useful, and why, if an Aeroforce guage was installed. I'm thinking about doing this as I already have the engine drained, so install should be easier now than it will be later.

Happy trails,

Keith

[daddyman]

Um, the vacuum tree...Does anyone know the part number for this piece? I have not been able to find it.

Also, the oil pan gasket: Is it reusable like the trans gasket, or should I get one of these also? I think I will flush the crankcase while I have it open, just in case.

Thanks!

Happy trails,

Keith

[myfirstbonnie]

Vacuum tree is available frm zzperformance for $15. The oil pan gasket can be reused if in good shape, but most parts stores carry them. Just remember that this gen has a motor mount attached to the pan so the motor will need supported from above to drop the pan.

[00Beast]

You don't need to remove the pan to flush the crankcase, just remove the plug...

[daddyman]

Finally the rain has dried out here, so I can continue!

For the lim gasket placement, I have seen differing recommendations about installing the gaskets dry, or installing them with a light spray of copper silicone rtv. Thoughts and comments?

I understand this is separate from the beads used on the crankcase rails and ends.

Thanks!

Happy trails,

Keith

[myfirstbonnie]

LIM gaskets are installed dry with the exception of the corners. Some use the black RTV and some use the red 27b.

Where the head and block meet, the rubber end pieces and the aluminum frame meet. Put some sealant in this corner, place the gaskets on, put more sealant on top in the same place and then install the LIM. Some do put sealant along both rubber ends top and bottom, but the aluminum framed side gaskets go on dry.

Also, on the coolant elbows, apply a light bead of sealant around the fitting just before the o-ring so when you slide them in it acts as a lubricant and then seals. The bead of sealant should be towards the end so it enters the LIM before the o-ring.

[daddyman]

Well, the engine is back together and running. Yeah!

It is, however, showing DTC's of P0122 and P1122, indicating low and intermittant voltage. I checked the voltage to the pins for the TPS harness as indicated in another thread, and they showed to be OK.

The car has also been going to a very high idle (2500-3200) for the first start of the day. It's chilly, and once it has warmed up, subsequent starts settle into about 1600-1700 (Intense PCM with higher set idle.).

Since it settles down, I don't think this would be a vacuum leak, as it is not consistant; but would a bad TPS have anything to do with the idle?

Thanks again for the assisatance.

Happy trails,

Keith

[redzmonte]

could be a vac leak, once the metal gets hot and expands then the leas seals up or mostly up.. Spary carb cleaner around the intake gasket areas and see if it bump the idle up when it hits the leak. also could be a cracked/unhooked vac line as well... hard to say.

TPS= Throttle Position Sensor, it will have everything to do with a high/bad idle.

Also P0122 is TPS sensor Most likly thie problem... if the throttle doesnt know where 100% closed/open is it would be idling high. P1122 is also a TPS code... find the problem causing the code and i bet you find the problem... could be a bad sensor, pinched wire or a few different things...

[00Beast]

Definitely sounds like a vacuum leak.

Why do you have a raised idle? 1600 RPM idle is insane, you'd only need that on a severely radical cam. 800 RPM should be more than enough for even a Stage 1 cam, but it doesn't appear you have anything but a stock cam.

[redzmonte]

I cant remember if there is a seal/gasket on the PCV cover like the L36 or not... when i did my moms Lesabre IMG it had a issure a day or 2 later where it would run funny and it did have a couple codes, ends up the PCV seal was missing.... I swear i reinstalled it... something to look at...

S

[00Beast]

There should be an O-ring on the PCV valve and a gasket for the cover. Mine was missing for 2+ years...