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Couldn't the timing belt path be designed so the belt is easy to replace?

The expense to change timing belts is a common question here. I change the timing belt myself on my early 90’s Corolla, but found it to be a difficult job. Not the actual changing of the belt. That’s no more complicated than lining up the 3 numbers on a combo lock so it opens.

What was difficult was supporting the engine and removing the front engine mount – you have to do this to get the belt into position.

The bolts to remove the engine mount were on so tight they tended to round over instead of letting loose like they should, and when the engine mount was removed, the engine twisted slightly, which made it difficult to re-install the mount. I supported the engine from above and from below, but still had much difficulty w/this. And removing the bolt that sets the tensioner was difficult too. It wanted to round over.

Anyway, it seems to me the timing belt path could be re-designed in a such a way that you wouldn’t need to remove any engine mounts. All you’d have to do its remove the timing belt covers and change out the belt. A 20 minute job. With time for beer break.

Are the engine designers just plain lazy, and don’t take into account the amount of work needed to change out a belt? What do you think?

I had to remove my alternator to change a thermostat, 03 blazer 6cyl, I have had to buy special torx bits for simple maintenance on a ford, I had to drill out rivets and put in bolts to replace a failed window motor. I think cars used to be based on easy repairs, now they are based on buy new and trade out of expensive repairs.

The first priority in any aspect of designing an automobile is reducing the total time/cost to build it. The engine is fully assembled when it is installed into the car. The timing belt in the Corolla was installed in a matter of seconds as was the complete engine. The cradles sold by Snap-On, etc., make it quite easy to support the engine and allow for lowering and raising the front of the engine to gain access to the work. An experienced mechanic with all the right tools and equipment can likely replace the timing belt in less than an hour. The designers don’t give a damn about the mechanics. And the mechanics just do the work, most earning the flat rate and beating the book.

Unless it’s warranty and then beating the book is often out of the question. :slight_smile:

And that’s why I’ll not buy a timing belt engine again. I replaced one on my '83 GTI, and it lacked the alignment marks…fun.

The 83-87 Toyota Camry was designed for that job to be easy. No engine mounts to disconnect, no supporting engines. There was a lot of space under the hood with the four cylinder engine. Distributor cap, wiring and plugs were way too easy and changing oil was a 10 minute job.

Toyota is better than some others. If one removes the wheel and inner fender liner, the front of the engine is fairly accessible. But in many cases, designers simply do not have ready maintenance high on their design goals. Heck, there have even been cars in the past that made changing sparkplugs a major production.

“I think cars used to be based on easy repairs, now they are based on buy new and trade out of expensive repairs.”

Cars ere rarely designed with easy maintenance in mind , at least not in the fifty years I’ve been driving and working on them . Some jobs on old cars are easy and others were PITA jobs same as brand new cars . I recently replaced a temperature sensor on my car and was pleased at the ease of the job - if I had a stronger fingernail I could have done the job without tools . As it was I needed a screwdriver .
Cars are disposable so there’s no real reason to design them for easy maintenance .

It seems that a vehicle designer’s guideline is that a vehicle must be repairable with little attention paid to the ease of doing that. Who would you ask to know more about that before you buy?

Who bothers to know whether an engine has a timing belt? Who thinks about the proximity of more than one dealer of a given brand if a dealer disappoints? Very few IMO.

The last car I remember being designed for easy repair was the Checker.

VW Bug for me.

@RemcoW–I think the King Midget even beats the VW Bug. One man could remove the 8 Horsepower Wisconsin engine in 10 minutes.

IMO, the timing belt was an attempt to reduce the manufacturing cost. A belt would be less expensive than a chain. It is also possible that the first manufacturer using the timing belt would have seen a maintenance job for the dealer at 60,000 to 100,000 miles. Others would have followed on if only to match the manufacturing cost advantage. Even a couple bucks per car can drive a decision.

Manufacturers seem to be moving back to timing chains, probably due to complaints from owners that don’t like the expense and time to replace them.

@jsanders–Count me in as an owner who won’t buy a car with a timing belt that needs to be replaced. We chose a 4Runner V-6 over an almost identical 4Runner V-8 back in 2003 because the V-8 had a timing belt that needed to be replaced over a timing chain. For the same reason, I didn’t consider the Honda minivan and bought a Sienna instead.

@Triedaq – 10 minutes, that is impressive. I’ll have to check out what that engine looks like now…

I can do a VW bug engine in about 15-30 minutes but have seen a team of two people take a bug engine out in a couple minutes at shows, though.

The timing belt is already routed for the shortest most efficient run at the front of the engine. The problem arises when the engine is put in a car and all the other accessories/mounts are added. Look at late model Honda Civics. You’re got to remove the steering fluid reservoir and cruise control to remove the upper t-belt cover. That’s not the fault of the engine. It’s just where those things need to be.

@Triedaq - My 2005 Honda Accord EX V6 has a timing belt. Mrs JT wants me to replace it after she starts work again (teacher; off for summer). With the tensioners, it is likely to push $1000. Still, the car is a couple grand less than the other finalist with a pushrod V6. I’m willing to suppose that the other car would have been as trouble-free as the Honda.

A better idea would be to replace the belt with gears.

VW Bug? no oil filter or fuel filter and I had to adjust the valves at every oil change. Also almost no heat or defrost and swing axles that made a Corvair seem likw a safety car.

If you keep rounding off bolts- get some 6 point sockets.

Lets get real about car design, all those cars that were so easy to work on were in the junk yard long before 10 years or 100,000 miles. People today frequently get 200,000 + withless repair and maintanence than those old cars.

I have done Toyota’s and its no ten minute job, but they are easier than most. They do take ten minutes just to remove the PS pump belt because of they way they are mounted. However I had a 79 Dodge Colt and in that one, it was a 10 minute job. Remove the alternator and ac belts. A few small bolts for the cover. Three bolts for the water pump pulley and three small bolts for the crank pulley, no big crankbolt in front that needed a lot of torque to remove. It was a piece of cake.

Mitsubushi has seen the error of their ways and have corrected this by making later models much harder to do.