Camry Forums - Toyota Camry Forum

Toyota Camry 2002-2006: Defective Engine Head Bolts/Head Gasket Issue

Has your mechanic or Toyota dealership come to the conclusion that you must replace your entire engine?

By Piyush Kayastha - October 1, 2015

This article applies to the Toyota Camry (2002-2006).

There has been a defect found with the 2002 to 2006 Toyota Camry's and RAV4's, which elude to bad head gasket condition where the motor loses coolant. The loss of coolant occurs at the back of the plastic intake manifold. The cause of this issue is irregular heat dissipation caused by a foam composite and the plastic manifold. This irregularity of heat breaks down a few of the "head bolts" threading and causes them to loosen up, or the threads to strip. When this occur, not only is the bolt useless now, but the hole it threads into is also faulty. This will cause a leak that cannot be repaired by simply using new bolts and a head gasket job. There is a solution that has been found and proven to be a good "fix," saving the owner from the costly job of replacing the entire engine. This article will introduce you to time-serts and helicoils.

Component Breakdown

Time-Serts

Time-serts, also known as "thread repair kits," are comprised of steel threaded bolts that resemble head bolts similar to the ones found on your Camry's cylinder head. Loctite is also provided for a secure bond. The use of a "tap wrench" tool is recommended to ensure the engine head bolt holes are the correct size to accept the "time-serts." Often, this is the choice of mechanics for those applications were customers have already tried using "helicoils," which have backed out and caused the leak to appear again. (Read on for more information about helicoils.) Because of the steel composition of time-serts, they will ensure the thread size is brought back to the correct size and provide a much stronger, more solid bond.

Figure 1. Time-sert kit.

Related Video: Time-Sert Thread Repair Kit

Helicoil Thread Repair

This is similar to time-serts, but has been found to not have as strong as a hold as the steel time-serts. They are installed into the corroded holes the same way as time-serts. It may also be necessary to use a "tap wrench" tool to create the hole needed to accept the helicoil.

Figure 2. Helicoil thread repair kit.

Related Video: Helicoil Installation

3/8" Bolts

Another solution is to use a slightly bigger bolt. However, you must still tap the existing "damaged" hole(s) to the proper size to accept the larger bolt. It might be wise to do all nine bolts (it is recommended not to touch the outer four bolts) at the same time. This is because over time, the other existing bolts will weaken due to the irregular heat dissipation caused by the intake manifold.

Figure 3. Using a large bolt to fill the void.

Scheduled Maintenance

If your vehicle is under warranty, engine replacement may be possible. If it is not under warranty, it is recommended to go the route of time-serts or helicoils. Any time your coolant system is serviced and/or your head gasket is being replaced, these bolts should be checked and addressed accordingly.

Common Questions

What year of the Camry's are affected by this?

The Toyota Camry, Scion and RAV4's between the years 2002 to 2007 have been affected by this defect.

Common Issues

Technical Service Bulletin TSBS2740

This problem relates to the engine head bolts breaking and damaging the threads, causing a coolant leak at the back of the cylinder head. The fix has been offered to use helicoils, time-serts, or other thread repair measures. Ultimately, engine replacement is recommended.

Related Discussions