GM 3.4L LIM Gasket replacement...

Status
Not open for further replies.
Joined
Aug 15, 2006
Messages
10,060
Location
Central Washington
Im investigating doing the LIM on my grandparents '01 Montana. Which is just peachy. Im sure I can do it, but what kind of tools and supplies will I need? That will be the kicker. It will get expensive fast buying fancy tools.
 
It's not a fun job and will require quite a few hours of work. I would suggest that you have them take it in and have it done. Then you get a warranty too!
wink.gif
 
Im sure it is not fun looking how deep the engine sits inside the dash. Still it will probably be cheaper than taking it in. Faster? Maybe not. This is pretty much my chosen profession anyway, so why not?
 
It's very messy too, plus I think you have to shift the engine forward and get to it from underneath. Depends on the setup in your vehicle.
 
You don't need any special tools.
I think you can remove the windshield wiper assembly for more room but I never did.
If you attempt this make sure you don't mix up the push rods. They are different lengths.
Probably take you most of an afternoon to do depending on how much cleaning you do.
I recommend pressure washing the engine first if its real dirty.

Good Luck
 
So you did it on one of these Vans? What about a torque wrench? Im thinking I might need to finally invest in one. I have a 20-200in-lb or so 1/4", but I will probably need a mid-range 3/8".
I had heard about the push rod issue. What a way to complicate things. Still, its probably best they end up in the same spot
 
Last edited by a moderator:
A torque wrench is an excellent idea when gaskets are involved and so that you don't break any of the bolts accidentally.

Also take the van for a drive to get the engine good and hot, then let is sit for about an hour before doing the work so it doesn't burn your hands.

The residual heat will make life a lot easier to crack things loose and you will stand a better chance at not breaking anything.
 
Yeah I've done quite a few intakes on this engine design.
Its been a while though.
Torque wrench would be a good idea but not mandatory.
You can probably rent/borrow a torque wrench from your local parts store.
You'll need a quality gasket set and silicone sealer
Oil and Filter
Coolant
2-3 cans of parts/brake cleaner.
Hand tools
scraper or razor blades for cleaning off old gasket material.
stiff bristle brush
rags

Change the o-ring on the oil pump drive plug while you're in there. They like to leak oil.

Tune up and plug wires aren't a bad idea too while you're in there if the mileage is high.
 
Originally Posted By: Rabbler
Tune up and plug wires aren't a bad idea too while you're in there if the mileage is high.

I wholeh-heartedly agree with the tune-up. Those vans are a bear!
 
Torque wrench is absoloutely mandatory. On the 3.4 in the Alero I recently did, I had to buy crow's foot wrenches to torque down a couple of the bolts.
Following the torque sequence and numbers in progresson is very important. Also, get a good gasket set. I recommend a Felpro Problem Solver gasket set. It includes the gasket maker for the part of the manifold you need to use it on. You can also get the new LIM bolts that are impregnated with threadlocker, or you can make sure the old ones are very clean, and put threadlocker on them. Regardless, clean out the old bolt holes very well (I used brake cleaner and q-tips).
This isn't an impossible task, but it isn't trivial. You might have a back-up mechanic on call if you get in over your head.
 
Last edited:
Ive put tune-up parts into the budgets, yes. I figure with the intake off is when it will be easiest. It has about 94k miles on it. Im also including the thermostat. I will look into adding the pump drive o-ring. Might do the forward O2s too.. Does it have one for each bank?
 
Last edited by a moderator:
Well, this is what I have..any additions/exclusions/changes?
Engine : Intake Manifold Bolt Set; FEL-PRO Part # ES72226, OHV engine; Loc. Lower; Replacement required
Engine : Intake Manifold Gasket; FEL-PRO Part # MS98003T {Set}, OHV engine; Valve cover gskts. & Upper set incl.; PermaDryPlus® int. manifold gskts. incl.
Fuel/Air : Fuel Rail O-Ring Kit; ACDELCO Part # 217461, {#17113034}, SEAL KIT,F/INJN FUEL RL
Cooling System : Radiator Cap; STANT Part # 10331, Safety Release Vented Cap (Open or Closed System) - 16 psi (SAE Range 14-18 psi)}
Cooling System : Thermostat; ACDELCO Part # 131124, {#24507563}, THERMOSTAT,ENG COOL 195 DEG, W/SEAL
Ignition : Spark Plug Wire Set; ACDELCO Part # 726UU, {7mm Wires #12192462}, WIRE KIT,SPLG
Ignition : Spark Plug; ACDELCO Part # 41979, {PLATINUM PLUG}, SPARK PLUG .060 GAP
Engine : Oil Pump Seal; DORMAN Part # 90441, {HELP! #10477565}
 
Originally Posted By: Onmo'Eegusee
Well, this is what I have..any additions/exclusions/changes?
Engine : Intake Manifold Bolt Set; FEL-PRO Part # ES72226, OHV engine; Loc. Lower; Replacement required
Engine : Intake Manifold Gasket; FEL-PRO Part # MS98003T {Set}, OHV engine; Valve cover gskts. & Upper set incl.; PermaDryPlus® int. manifold gskts. incl.


Pretty sure that Fel-Pro has a kit that includes all of this in one package, at least that's how I got mine. I think you can save a couple of $$$ by ordering it this way.
 
I just looked it up on felpros site. Theres the barebones kit with just the LIM and UIM gaskets, and that one with valve cover gaskets and some other misc gaskets that Im not sure what they are for...hm.
 
Originally Posted By: Onmo'Eegusee
So you did it on one of these Vans? What about a torque wrench? Im thinking I might need to finally invest in one. I have a 20-200in-lb or so 1/4", but I will probably need a mid-range 3/8".
I had heard about the push rod issue. What a way to complicate things. Still, its probably best they end up in the same spot

I recommend a CDI/Snap-On or PI torque wrench:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=130303460345
 
Originally Posted By: Onmo'Eegusee
I am looking at a PI down in Oregon. Its used, but its been recalibrated professionally.

Buying an used torque wrench is like buying used underwear.

Torque wrenches are precision instruments. If it has been dropped before or used to break bolts loose, that could potentially damage it. When you buy an used one, you do not know how it has been treated.

I would just buy a new one. The CDI one that I listed earlier will last you many years.
 
My 1/4" and big 1/2" were used. Both are calibrated and well within specifications. I found a snap-on 5-75ft-lb with flex head. I am thinking that feature may be useful here, and I think I will jump on it.
If I get a 20-100ft-lb, I will have a hole, since my 1/4" only goes to 200in-lb or 16 2/3ft-lb so I will have a hole of 3 1/3 but the bottom 20% is not considered accurate, so its even larger.
 
Last edited by a moderator:
Originally Posted By: Onmo'Eegusee
My 1/4" and big 1/2" were used. Both are calibrated and well within specifications. I found a snap-on 5-75ft-lb with flex head. I am thinking that feature may be useful here, and I think I will jump on it.
If I get a 20-100ft-lb, I will have a hole, since my 1/4" only goes to 200in-lb or 16 2/3ft-lb so I will have a hole of 3 1/3 but the bottom 20% is not considered accurate, so its even larger.

You should get a 5-75lb like the one in my link.

A flex-head torque wrench only flexes 15 degrees I think? Unless they have changed.

How much are you saving with the used Snap-On compared to a new CDI? CDI makes the torque wrenches for Snap-On.
 
Status
Not open for further replies.
Back
Top