Replacing Oil Pan Gasket: Step-By-Step Guide For 90 Xj

Replacing the oil pan gasket on a 90 XJ is a challenging task that requires careful preparation and execution. It is essential to jack up the front end of the vehicle, allowing the axle to droop fully for easier access to the oil pan. Removing the starter, oil pan bolts, and exhaust components may also be necessary. When installing the new gasket, it is crucial to ensure proper alignment and torque specifications for the bolts. Some recommend using RTV silicone or gasket makers in addition to the gasket itself for a better seal. Taking the time to prepare and follow instructions carefully will result in a successful oil pan gasket replacement.

Remove the axle and starter

To remove the axle and starter when installing an oil pan gasket on a 90 XJ, follow these steps:

First, jack up the front end of the XJ as high as possible and secure it with jack stands under the body, not the front end. This allows the front axle to droop as low as possible, giving you more clearance to work. Remove the front tires and let the axle drop completely. You can also turn the wheel to the left to allow for more room.

Next, disconnect the negative battery cable. Drain the oil and remove the starter. The starter bolts are typically 14mm on the bottom and 15mm on the top. With the starter out of the way, you can now access and loosen the oil pan bolts. Support the oil pan with a floor jack and remove the bolts securing it.

At this point, you can carefully lower and remove the oil pan. You may need to lower the back half of the pan first and pull it out from under the transmission, allowing the axle to move forward. Once the oil pan is out, you can continue with the rest of the oil pan gasket installation process.

Use a one-piece moulded rubber gasket

If you're installing an oil pan gasket on a 90 XJ, you might want to consider using a one-piece moulded rubber gasket. This type of gasket is designed for modern engines that use heavier, cast oil pans to add strength to the vehicle frame. The one-piece construction makes installation easier than multi-piece assemblies or RTV sealing.

• The gasket's rigid carrier provides durability, perfect alignment, and an instant fit.
• Oil pan SnapUps® are features that hold the gasket in place for quick bolt installation.
• Silicone rubber is used to eliminate leak paths, especially in problem corner areas.
• Torque limiters prevent over-compression of the gasket and deformation of sealing surfaces.
• Blue Stripe cork-rubber combines the qualities of cork and rubber gaskets, offering good shape retention, flexibility, and compressibility for a strong seal.

When installing a one-piece moulded rubber gasket, it's important to follow the manufacturer's instructions and ensure proper torque values for the pan bolts. Additionally, consider using studs or alignment dowels to keep the gasket in place during installation.

Jack up the Jeep and let the axle droop

Jacking up your 1990 Jeep Cherokee XJ and letting the axle droop is a crucial step in replacing the oil pan gasket. Here's a detailed guide on how to do it effectively:

First, use a jack to raise the front end of your Jeep as high as possible. It is important to place jack stands under the body of the Jeep, rather than the front end, to ensure stability and allow the front axle to droop as low as possible. This step is crucial in providing the necessary clearance to access the oil pan.

Next, remove any parts that may obstruct your access to the oil pan. This may include the exhaust, steering components, and the starter. By removing these parts, you create a more spacious work area and make it easier to manoeuvre during the gasket replacement.

Now, focus on the axle. Disconnect the track bar at the bracket and, if necessary, the sway bar. These steps will provide additional clearance and allow the axle to droop further. If your Jeep is not lifted, you may also need to disconnect the shocks to achieve the desired droop.

At this point, you should have maximised the droop of the front axle. This will make the process of removing and installing the oil pan significantly easier. Remember to turn the wheel all the way to the left to gain even more room for the pan.

Before proceeding with the oil pan gasket replacement, it is recommended to clean the area thoroughly, especially if there are leaks or dried dirt. Use a pressure washer or similar tool to ensure the work area is free from debris and old fluids.

By following these steps, you will have successfully jacked up your Jeep and achieved the necessary axle droop to perform the oil pan gasket replacement. Remember to work safely and wear appropriate protective gear throughout the process.

Remove the exhaust and steering parts

To remove the exhaust and steering parts, you will need to jack up the front end of your XJ as high as possible and secure it with jack stands under the body. This will allow the front end to droop as low as possible.

You will then need to remove the exhaust and any steering parts that are in the way. This may include the trackbar brace, the trackbar at the bracket, and the shocks. You may also need to disconnect the sway bar to get more travel on the front axle.

Once you have removed the necessary parts, you can continue with the oil pan gasket installation.

Use RTV on the gasket and pan

When installing an oil pan gasket on a 90 XJ, using RTV on the gasket and pan can be a helpful supplemental sealer to ensure a leak-free assembly. Here are some detailed instructions on how to use RTV effectively:

Clean and Dry Surfaces:

Always start by ensuring that the gasket and the engine block are clean and dry. Any residual oil or dirt can affect the adhesion of the RTV and compromise the seal.

Apply RTV in the Right Places:

RTV should not be applied to the entire gasket. Instead, focus on the corners of the gasket and/or stepped casting areas that have gaps. These areas are more prone to leaks, and using RTV will help fill in those gaps for a better seal. Additionally, applying RTV to the corners first can prevent smearing during installation.

Use the Right Amount of RTV:

Remember that a little RTV goes a long way. Apply a small amount, just enough to fill the gaps and create a thin layer. Consult the repair manual or the manufacturer's recommendations for specific instructions on how much RTV to use and where to apply it.

Install the Gasket Promptly:

Once you've applied RTV, it's important to install the gasket within a few minutes. The RTV will start to set and dry, so work efficiently to avoid any delays.

Allow RTV to Cure Fully:

After you've installed the gasket and torqued it into place, give the RTV enough time to cure completely. Typically, RTV needs around 24 hours to fully cure. Do not rush the process or drive the vehicle during this curing period.

By following these instructions, you can effectively use RTV on the gasket and pan when installing an oil pan gasket on your 90 XJ, ensuring a durable and leak-free seal.

Frequently asked questions