Dorman Aluminum A/C Line Block-Off for 5/16" Line — 800-994, Corrosion-Resistant Seal

The Dorman 800-994 is an aluminum block‑off designed to securely seal a 5/16" air conditioning line, restoring system integrity while resisting corrosion.

When a short section of A/C hard line or tubing is damaged, the Dorman 800-994 Aluminum Line Block Off offers a focused, cost‑effective alternative to replacing the entire assembly. Built from durable aluminum, this block‑off stops leaks, helps return the system to proper operating temperatures, and reduces the risk of future failure from rust or corrosion. It installs quickly and is compatible with standard 5/16" lines used in many automotive systems.

How does this block‑off help fix a leaking A/C line?

The Dorman 800-994 provides a reliable mechanical seal to isolate a damaged section of tubing without the expense and labor of replacing the entire line. It restores a closed refrigerant circuit so the compressor, evaporator, and condenser can operate normally again.

• Seals a 5/16" A/C hard line leak point to prevent refrigerant loss
• Aluminum body resists rust that can cause repeat failures
• Saves time compared with full-line replacement

Is the 800-994 simple to install for DIY and shop technicians?

Yes—this part is engineered for straightforward installation so technicians can repair only the failed section. Typical installation requires basic hand tools and standard A/C service procedures; it’s a practical option for fast turnaround.

• Quick fit for 5/16" diameter lines with common shop tools
• Reduced labor compared to removing and replacing assemblies
• Compatible with Dorman’s A/C Line Repair Kit options for expanded repairs

What makes this aluminum block‑off more durable than other options?

Constructed from corrosion‑resistant aluminum, the 800-994 is less prone to rust and degradation than many plated or steel alternatives. That material choice helps prolong the life of the repair and limits the chance of future leaks at the same joint.

• Aluminum construction resists oxidation and environmental corrosion
• Sturdy build maintains seal under typical automotive operating conditions
• Designed to hold refrigerant pressure when installed correctly

What support is available if I need help selecting or installing this part?

Dorman backs this product with technical assistance from certified specialists, so technicians and DIYers can get guidance on fitment, installation best practices, and compatibility. Documentation and customer support help minimize installation errors and speed diagnostics.

• Access to Dorman ASE Blue Seal Certified technical support
• Part also available within Dorman A/C Line Repair Kits for comprehensive fixes
• Product literature and fitment guidance for common vehicle applications

Who is this for? The Dorman 800-994 Aluminum Line Block Off is ideal for automotive technicians, service shops, and experienced DIYers who need a durable, economical way to stop a refrigerant leak on a 5/16" A/C hard line. If you want to save labor and parts cost by repairing only the damaged section—while choosing a corrosion‑resistant solution backed by manufacturer support—this block‑off is a practical component to keep on hand.