DIY Guide: The 3800 Coolant Elbow & Intake Gasket Fix (The #1 Repair)

[Anthony Cipriano]

The Puddle Under the Passenger Side: Is your LeSabre marking its territory with orange Dex-Cool?

Scenario A: You find a puddle of coolant on the ground under the passenger side of the engine, right below the alternator.

Scenario B: You pull the oil dipstick and it looks like a "chocolate milkshake". (This is the nightmare scenario).

The Fixes (Do NOT use plastic parts!): The factory used plastic for critical cooling components. Over time, heat cycles turn them brittle. When you repair this, you must upgrade to metal.

1. The "Killer" Elbows (External Leak)

The Part: Dorman 47065HP (Aluminum Coolant Elbows).

The Job: The belt tensioner assembly has two plastic elbows that route coolant into the engine block and intake. They eventually crack and spray coolant everywhere.

The Upgrade: Replace them with the cast aluminum versions. They will outlast the car and never crack again.

2. The LIM Gaskets (Internal Leak)

The Part: Fel-Pro MS 98014 T (Aluminum Frame).

The Job: The factory lower intake manifold (LIM) gaskets were plastic. Dex-Cool eats them, allowing coolant to mix with your oil.

The Upgrade: The "T" in the part number stands for the updated metal-framed design. This is a permanent fix.

Pro Tip: While you have the intake off to do the gaskets, replace the upper plenum (mentioned in the other thread) as preventative maintenance. You are already 90% of the way there.

Cost Breakdown:

Elbows: ~$10

Gasket Set: ~$50

Labor (Shop): Expect quotes of $600+ because of the tear-down time.

Labor (DIY): A Saturday afternoon and a 10mm socket.

Need help? Reply below.

 

[lilpoindexter]

i use "GM" branded al-yoo-min-i-um elbows from amazon. They are probably fake and made is some dudes backyard in turkey or whatever, but so far so good.

 

[seymourj98]

"A Saturday afternoon" maybe ambitious unless you've already done the job before. If it's your first time, I'd play for a whole day.

As a bonus, this is a great time to do valve cover gaskets and spark plugs as well. The rear bank is significantly more accessible without the UIM.

 

[Anthony Cipriano]

i use "GM" branded al-yoo-min-i-um elbows from amazon. They are probably fake and made is some dudes backyard in turkey or whatever, but so far so good.

Like these?

"A Saturday afternoon" maybe ambitious unless you've already done the job before. If it's your first time, I'd play for a whole day.

As a bonus, this is a great time to do valve cover gaskets and spark plugs as well. The rear bank is significantly more accessible without the UIM.

With the right tools anything is possible! But yes in many cases it can take awhile.