Timing Belts & Timing Belt Component Kits

Did you know that an old timing belt could cause catastrophic engine damage? It is important to understand what a timing belt does and the difference between interference and non-interference (free-running) engines.

Put simply, the synchronization between the crankshaft and camshaft is accomplished with the help of the timing belt, and these two moving parts cause the intake and exhaust valves to open and close in very close proximity to the pistons.

Interference Engine:
Disrupted synchronization in an interference engine allows the piston and the valve to collide. Damage can occur to valves, pistons, or heads, and in some cases, completely ruin the engine.

Non-Interference (Free-Running) Engine:
In the free-running engine with the crankshaft still moving, there is enough clearance between the valves and pistons, even if the camshaft stops with some valves fully open. The valves should not hit the pistons. However, in vehicles with dual camshafts, there is still a small risk that valves could collide and cause damage.

Image courtesy of Gates

Look under the “Engine” category in the RockAuto catalog for your specific vehicle to find out if it has a timing belt. Do you not see a timing belt? The engine might have a timing chain rather than a belt. Timing chains have replaced belts on many of the newest four and six cylinder engines and typically last for the life of the engine. (Larger engines almost always use timing chains.)

Approximately 70% of vehicles equipped with a timing belt have an interference engine. However, even with an interference engine there is no need to lose sleep worrying. Just follow the engine manufacturer’s recommended replacement interval. That can be found in the owner’s manual or repair manual (under “Literature” in the RockAuto catalog). The typical maintenance interval for older engines is 60,000 miles (100,000 km), but it could be different (longer) for your specific engine.

Gaining access to the timing belt requires removing a lot of other parts. Repair manuals usually recommend replacing timing belt tensioners and pulleys along with the belt. If the belt is worn, then the other parts are nearing the end of their service lives, too. The water pump is behind the timing belt on some engines and can also be more easily replaced while everything is already disassembled. RockAuto has Timing Belt & Component Kits for many engines that conveniently include the additional parts that should be replaced along with the belt. The “Engine” category is where to find timing belts, tensioners and kits from brands you trust including Aisin, Continental, Dayco, DNJ and Gates.

Typical Timing Belt Kits With and Without Water Pump

Forum of the Month

Dodge-Dart.org is dedicated to the 2013+ Dodge Dart. This forum aims to be a friendly, educational community dedicated to everything about the new Dodge Dart. To take full advantage of the site, please register - It's QUICK and FREE.

Some of the more popular features of Dodge-Dart.org include an image gallery, calendar of events, a sub-forum for the Dart SRT 4, general maintenance/repair, and modification topics.

If you are the administrator or member of a forum and you would like to see your website featured in an upcoming newsletter and receive a discount code to share with your members, contact marketing@rockauto.com.

Repair Mistakes & Blunders

I got my first car (a 1970 Renault R-16) in 1981. Shortly after buying it, the Renault developed a grind when shifting from first to second gear. Of course, this bothered me, so I had to order a new clutch, plate and throw-out bearing from FRANCE! Parts were hard to find for a Renault in 1980...

After spending the better part of the day learning how to extricate the transmission, which involved draining its oil and the coolant from the radiator, I was ready to install the new clutch.

I put the clutch plate and clutch back onto the flywheel and simply rested it on the aligning pins. But when I reached into the car to grab the bolts, I bumped the shifter, and the new clutch and clutch plate fell off the alignment pins! Did it simply fall onto the ground? NO, the entire assembly that shipped to me from FRANCE fell right into the oil and coolant filled drain pan that was still under the car!

Needless to say, the car sat on jack stands for three more weeks while I waited for those parts to ship from FRANCE.

But that experience did teach me to not cut corners and keep my shop clean!

Ed on the East Coast

Tell us about your most infamous auto repair blunder or unconventional fix. Use your woe to help others avoid similar mistakes or share off-the-wall solutions that worked (at least for a while!). Please e-mail your story to flamur@rockauto.com. Include your mailing address and if you would like a RockAuto T-Shirt (please let us know your shirt size) or Hat if we publish your story. See the T-Shirts and Hats under Tools & Universal Parts in the catalog. The story will be credited using only your first name and your vague geographic location (state, province, country, continent, etc.) so you can remain semi-anonymous!

Automotive Trivia

Your diesel pickup runs out of diesel exhaust fluid (DEF) and goes into limp-in mode. Is urine an acceptable substitute for DEF in an emergency?

A. Yes, urea is the active ingredient in DEF and urine is a source of urea.
B. No, DEF is more than 30% urea while urine typically contains less than 2%. The computer would detect something other than DEF was in the reservoir and the engine would remain in limp-in mode.
C. Yes, but only if the truck is a rental vehicle.

I Became Curious About Diesel Exhaust Fluid Injection

With Volkswagen diesel emissions in the news and a diesel VW Jetta in my brother’s family fleet, I became curious about urea injection, a technology missing from the VW diesels. What is it again? How is it holding up after more than five years of use in countless diesel trucks and cars? Can VW diesels be retrofitted?

Diesel exhaust fluid (DEF) is roughly 70% water and 30% urea. It is injected into the hot exhaust pipe upstream from the catalytic converter. The high heat transforms the urea into ammonia and carbon dioxide. The ammonia reacts with harmful nitrogen oxides in the catalytic converter to form nitrogen and water that exit the tailpipe.

DEF injection systems seem to be holding up well after millions of miles of use in diesel pickup and van fleets. Aftermarket parts manufacturers make solutions for problem prone original equipment (OE) parts. Looking at diesel vehicles in the RockAuto catalog (under “Exhaust” category), the caps for DEF tanks need to be replaced if they crack or get lost. Dorman built a better DEF pump for 2011 and newer Ford diesels (part number 904369). Otherwise, the OE parts seem to be holding up well.

Dorman DEF pump for 2011 and newer Ford diesels

The water in DEF made me wonder about freezing. The urea lowers the freezing point by about 20 degrees F (10 deg. C), but that is not enough to keep the fluid from freezing in many parts of the world. Most systems are designed so that the DEF can freeze without causing harm. The storage tanks are oversized to allow for expansion and a heating system thaws the DEF so it is ready to go when the engine/exhaust reach operating temperature. Thawed DEF retains the proper concentration of urea.

DEF can get funky if it is more than one or two years old, especially at warmer temperatures. It is probably a good idea to drain DEF (as well as diesel fuel) if a vehicle is stored long term.

How about fixing those Volkswagens by simply tapping into the exhaust pipe and using a windshield washer reservoir and pump to deliver DEF? Unfortunately, DEF systems are not stand-alone. For it to work, computers must deliver just the right amount of DEF at the right time.

Too much DEF could cool the exhaust gas to the point where the catalytic converter stops working and/or is damaged. DEF consumption is typically only one to three percent of fuel consumption. Too much DEF would annoy owners who need to keep refilling their DEF tanks.

The cost of a retrofit would likely be thousands of dollars for parts and thousands of dollars for labor per vehicle, even if expensive parts such as computers and catalytic converters could be reused. The cost of new wiring harnesses, exhaust pieces, DEF plumbing and electronics would add up fast. That Dorman DEF pump for Fords I mentioned above costs more than $200 by itself. The VWs are compact and mid-size vehicles. Finding space to install new components would be difficult. Older vehicles may have a lot of miles, corrosion and other individual problems.

DEF injection systems are a proven way to lower nitrogen oxides and core concepts are relatively easy to understand. But, all the details involved with a DEF retrofit would be a huge challenge for engineers, parts manufacturers, installers and accountants.

Tom Taylor,
RockAuto.com

To read more of Tom's articles, click this link and choose from story titles on the Newsletter Archives page.

This is my 1985 GMC S15 Jimmy Woody Edition. The motor was bad when I bought it (it has since been rebuilt), but the exterior and interior were in near perfect condition.

What makes my Jimmy special is that I have not seen any others like it. I did find an old GMC ad that had a picture of a Woody edition that looks exactly like mine. This vehicle has been very fun to work on and restore to its original glory. RockAuto has become my go-to for parts (I recommend RockAuto to all my friends and family).

Some of the parts that I have purchased for my Jimmy have been an alternator, valve cover gaskets, filters, oil pressure sender, transmission mounts, shocks, idler arm, flex plate and door seal weather strips.

Thanks RockAuto!
Christina in Texas

© 1999-2015 RockAuto, LLC - Madison, Wisconsin USA. RockAuto name, logo and ALL THE PARTS YOUR CAR WILL EVER NEED are registered trademarks of RockAuto, LLC. Manufacturer names and logos in the RockAuto catalog are trademarks of their respective companies and are used only to identify their products. All rights reserved.