Why The Demise of Timing Belts?

[Klutch9]

Of the 3 vehicles we own, the only one with a timing belt is the Miata. However, since it has a non-interference engine, I'm not really all that concerned with replacing it. I have no idea if it has ever been replaced, but I looked at all that I could when I did the valve cover gasket last month, and it still looks to be in good condition: No cracks, still rigid, etc.

 

[SwampSurvivor]

Originally Posted By: Klutch9
Of the 3 vehicles we own, the only one with a timing belt is the Miata. However, since it has a non-interference engine, I'm not really all that concerned with replacing it. I have no idea if it has ever been replaced, but I looked at all that I could when I did the valve cover gasket last month, and it still looks to be in good condition: No cracks, still rigid, etc.



On a non-interference engine it's not as unacceptable. Drive it until it snaps and replace. No damage done.

 

[Silverado12]

The 250 Chevy inline six and the Iron Duke 2.5 both had gear setups.

 

[Mykl]

Originally Posted By: millerbl00
Wow really? Going out of your way to hound us....


Yeah, I'm going out of my way to hound you by openly sympathizing with your views on a particular subject.

 

[friendly_jacek]

I've heard that timing belt interval was 30,000 miles in Yugo. Not sure if true. Mine didn't last that long.

 

[grampi]

Originally Posted By: Silverado12
The 250 Chevy inline six and the Iron Duke 2.5 both had gear setups.


I had a '66 Bel Air with a 250 and it's still the longest lasting engine I've had yet...it went 309K and was still running when the tranny died...no tellin how long that motor would've lasted...

 

[Dave Sherman]

Originally Posted By: Silverado12
The 250 Chevy inline six and the Iron Duke 2.5 both had gear setups.


The Iron Dukes started with plastic timing gears

. After having one eat a few teeth on the highway and having to pull the engine and camshaft out to fix it, I wished it had a chain or belt.

 

[SwampSurvivor]

Originally Posted By: Silverado12
The 250 Chevy inline six and the Iron Duke 2.5 both had gear setups.


The later Ford I6 has them as well.

 

[cjcride]

Originally Posted By: BrewCity
I would guess that another factor is those "total cost of ownership" calculators at websites like Edmund's and such. It's much easier for somebody to do their research on scheduled maintenance these days. Seeing that there's a $900 service at 100,000 miles isn't going to win that car any points with a buyer.
This is a big reason. I would hear non DIY'ers say it doesn't have a timing belt so there's less work to pay for.
Some are people who probably don't even check their oil level

 

[Klutch9]

Originally Posted By: Miller88
Originally Posted By: Silverado12
The 250 Chevy inline six and the Iron Duke 2.5 both had gear setups.


The later Ford I6 has them as well.


Didn't the Ford Cologne 4.0 V6 also use some odd jackshaft timing setup?

 

[sasha]

Timing belts are garbage period!!! Glad they are disappearing.

 

[Mykl]

Originally Posted By: friendly_jacek
I've heard that timing belt interval was 30,000 miles in Yugo. Not sure if true. Mine didn't last that long.


Same requirement for the engines Porsche put in the 924/944/968. The annoying part about it was that to do it right you needed to purchase a proprietary and expensive tensioning tool. I'm told there are less expensive tools that do the trick, but I can not personally attest to how effective they are.

 

[SwampSurvivor]

Originally Posted By: Klutch9
Originally Posted By: Miller88
Originally Posted By: Silverado12
The 250 Chevy inline six and the Iron Duke 2.5 both had gear setups.


The later Ford I6 has them as well.


Didn't the Ford Cologne 4.0 V6 also use some odd jackshaft timing setup?


The OHV ones were a simple chain setup. To convert the 4.0 OHV to OHC, Ford did some screwy stuff to save costs (and use the same head/ camshaft, I believe).

One chain from the crankshaft to a balance shaft.
Second chain from crankshaft to original camshaft location (no camshaft).
Third timing chain from original camshaft to left-head overhead cam.
Fourth chain from "original camshaft" location on back of engine to right head.

 

[E365]

I'm planning on buying a Focus 1.0 turbo three with the oil bathed timing belt. Should be an interesting "experiment"

 

[supton]

Originally Posted By: Miller88
The OHV ones were a simple chain setup. To convert the 4.0 OHV to OHC, Ford did some screwy stuff to save costs (and use the same head/ camshaft, I believe).

One chain from the crankshaft to a balance shaft.
Second chain from crankshaft to original camshaft location (no camshaft).
Third timing chain from original camshaft to left-head overhead cam.
Fourth chain from "original camshaft" location on back of engine to right head.


So that's what they did. My brother got bit by that setup when it failed. One of the chains failed (the one oh the back?) and he swapped motors. I think that motor didn't last long before the similar problem showed up. At that point he was done.

 

[sasha]

Originally Posted By: E365
I'm planning on buying a Focus 1.0 turbo three with the oil bathed timing belt. Should be an interesting "experiment"

That could be the next best thing. but remember, change your oil! Ignore the oil, grenade your engine.

 

[SwampSurvivor]

Originally Posted By: sasha
Originally Posted By: E365
I'm planning on buying a Focus 1.0 turbo three with the oil bathed timing belt. Should be an interesting "experiment"

That could be the next best thing. but remember, change your oil! Ignore the oil, grenade your engine.


I have mixed feelings on that :S

I like the turbo 3. I like the low end torque of the ecoboost engines. I like the fuel economy.

I'm afraid of timing belts, especially belt driven oil pumps!

Time will tell!

 

[ARB1977]

The next big thing is here. Keeping things simple is the thing of the past.

 

[ARCOgraphite]

I prefer timing belts on OHC, but the engineers have to package the engine so they can be changed, if not I guess its chains. Most likely the tight packaging forced chains. cHAINS ARE TOUGHER ON THE LUBRICANT AND VICE-VERSA. Hydralic tensioner sticking and excessive chain wear were common over the past 15 years. My BMW M 3.2 died early (68Kmiles) due to chain guide disintegration due to lubricant incompatibility (tech said).

 

[supton]

Originally Posted By: Miller88


I'm afraid of timing belts, especially belt driven oil pumps!

Time will tell!


Why? Motor will trash itself if the pump dies for any reason. If the belt breaks the engine stops no matter what. Seems more likely that the drive to the pump is what fails suddenly, so, if the engine stops suddenly because of belt breakage due to the pump binding (ingestion of garbage, whatever) then it is more apt to not trash the bearings, or at least that is what it seems to me.

Then again it could be a whole 'nudder new can of worms. I wonder how hard it will be to change an oil-bathed timing belt if it becomes a "yeah, it really doesn't last longer than 150 or 200k."