Timing belt replacement

brucer2

Timing chains on OHC engines are not without their own problems. Chains have no natural dampening, the way a belt does, and so needs chain guides to provide tension to the chains so they don't flop around and oscillate. The guides ate very often faced with plastic, and in a number of applications, have been known to break. The tensioners are usually hydrualic, without much oil flow, and are sensitive to getting blocked from crud/sludge. I still prefer chains.
When belts are changed, idler and tension pullies should always be checked or replaced. This is probably more important than changing water pumps. Water pumps last a very long time if the cooling system is well maintained.

isellhondas

Changing a clutch and not replacing the throwout bearing.

Been there.

paul29

Can anyone tell me which auto manufacturers recomend that the water pump or crankshaft- camshaft seals be replaced when doing the recomended timing belt change.Would this not be in the maintenance section of the owners manual and/or service manual ?

mrdetailer

I've always found this maintenance to be recommended not by the manufacturer, but by the service professionals who specialize in maintaining these cars. I've also learned this from excessive duplicate repairs for replacing timing belts after a water pump failed, after seals cracked and leaked, and after tensioners ate the belt a few thousand miles after replacement.

On the Water pump. On my Mazda as it reached the 120,000 mile checkup I not only spoke with my mechanic, but called the parts department of my local dealer. Both verified that most pumps didn't last long after 120,000 miles. My Subaru mechanic recommended waiting until 150-160 since they are generally more stable.

8u6hfd

Most Honda motors are of interference design. So if the belt snaps, kiss your engine goodbye. In this case it's preventive maintenance.

isellhondas

Still, not worth taking the chance. do it at 105,000 miles and forget about it.

spokane

Isellhondas, I agree with you that car owners should not be irked at the need to replace a timing belt at 90K to 105K miles. But a number of people do become upset when they learn of this need. Do you suppose this is due to the fact that they became spoiled by the lack of need for similar preventive maintenance cost on their old pushrod engines? A rhetorical question: Since this item is fairly expensive, should the salesman inform the prospective new car buyer of this cost?

Mr_Shiftright

The only advantage that the old pushrod engine had with a timing chain is that the chain would rarely break. But I used to see many sloppy, noisy chains that contributed to lazy timing and poor running. So if you neglect oil changes or don't pay attention to the chain tensioner or guide wear on the chain guide, well, you could have equally troublesome issues. I just saw a Toyota pickup towed in (somewhat older model), and the chain guide had worn so badly it fell into the chain and timing gears and seized the engine (at a slow speed). So that repair easily cost the price of a timing belt replacement.

No free lunch if you don't do the maintenance, belt or chain or gears.

spokane

Yes, Shiftright, there's no free lunch. It seems to me that a pushrod or flathead engine that is otherwise clean will often have an accumulation of residue at the timing chain and sprockets due to wear of the sprockets and/or the poor flow of oil that's often inherent in the engine design.

isellhondas

I just don't think it's such a big deal! No..I don't tell my customers..." After 105,000 miles you will need to replace your timing belt"

Now, if they ask, I'll be happy to tell them.

With the new CRVS and S-2000's I don't say..." Now, this model uses a timing chain...at some point it may wear and need to be replaced"

A buddy had a timing chain ship on his Pontiac once. I remember it bent some pushrods and something else had to be replaced. The teeth on the plastic timing gear had worn out causing the chain to slip. We had to pull the oil pan to clean out the broken plastic so it wouldn't plug the oil pump screen.

Another time I remember changing timing gears on an old 6 cyl Chevrolet. No chain, just a fiber timing gear that stripped out.

Any system can and will fail at some point.

Not a big deal!

cleal1976

How do you replace and set the timing belt on a 1998 Ford Contour?

alcan

If you're looking for step by step instructions, try the following in this order:

1: purchase an Alldata DIY subscription at http://www.alldata.com/products/diy/index.html

2: buy a Haynes manual

3: check if your local library has the manual available