Ford V8 Engine question - timing belt, timing chain, what's up ? BS or no.

[gh1950]

So I went to look at a 2002 Ford Expedition. Relatively low mileage,

The owner was not from around here, and by the number of cars in his yard and equipment, I could tell that he as a "flipper" and you know what ODT thinks of them.

Any way, he is putting out the razzle dazzle. He stated that the timing chain had broken, it had dropped (bent) a valve, and he had replaced all the valves. He said it was because the prior owner had not have the chain serviced at 100,000 miles.

Weeeeeelll, I have the same 4.6L V8 in my truck, earlier version, some differences, but it has a chain, and I mentioned that my understanding was that a chain did not require servicing or replacement (as a maintenance item), and that I thought that in the rare event a chain broke, it would not drop a valve.

He said that was true for my engine, but not for later models of the same engine, and that regular servicing of the chain was recommended.

I looked it up, and in 2005 Ford introduced a 3 valve SOHC version of this engine (mine is a 2 valve). So there's an extra valve.

BUT I have no found any discussion of the chain being a maintenance.


Bottom line, was he full of BS, or is this something I need to know?

 

[Kyzrsoze]

Some manufacturers quote a recommended replacement interval for timing chains, but I'm not sure if it's true of the early Ford triton engine. I'm willing to bet that ford doesn't require a timing chain replacement at 100k. It's reasonable to expect high mileage out of timing chain, and they tend to stretch over time rather than break, generally lasting until the engine is worn out.

In general the two valve ford V8s are solid in this regard, where the 3 valve versions 2004+ are trouble. Timing chain guides and cam phasers (Ford's version of variable valve timing) are the issue. I wouldn't worry about your truck. I'm also not sure i'd trust the guy selling the Expedition.

 

[Matt Mcconnell]

It's b's. The 4.6 is fine for many many miles. Defiantly not a regular maintenance item.I've never seen one break on a 4.6. But ive saw several guides and tensioners wear out. It will Be very noisy when that happens though. You'll get plenty of warning.

 

[harrycalahan]

The chain on the tritons dont need serviced. The tensioners and guides do. Using cheap oil filters w/o anti-drainbacks cause for a tick at start up. That tick is the chain slapping the guides before the tensioners gain pressure. Multiply that over the years and a large portion of your guides are now laying in your oil pan instead of guiding the chain. So a neglected engine in this scenario could absolutely cause excessive chain slop and failure. My 2v 4.6 has 99k on it and started ticking at start up earlier this year even with a good filter. She’ll be getting a new timing set this winter. Probably an oil pump too while Im there.

The 3v tritons suffer mainly from roller followers failing. Check out the video and see if 3v’s are right for you. They do require extra loving and care.

 

[spencer60]

I can remember as a teenager replacing many a timing chain that stretched and jumped a notch. Usually on a friends GM product.

I don't know if that's still a thing, or of the metallurgy is so much better than on those 60s cars timing chains just don't stretch enough to matter though.

 

[harrycalahan]

I can remember as a teenager replacing many a timing chain that stretched and jumped a notch. Usually on a friends GM product.

I don't know if that's still a thing, or of the metallurgy is so much better than on those 60s cars timing chains just don't stretch enough to matter though.

Tensioners take up chain stretch on modern engines. No use of them in the 60’s plus several auto makers had the bright idea of nylon cam gears.

 

[gh1950]

Thanks to all for the info, cleared up some things for me.

 

[RSB]

So I went to look at a 2002 Ford Expedition. Relatively low mileage,

The owner was not from around here, and by the number of cars in his yard and equipment, I could tell that he as a "flipper" and you know what ODT thinks of them.

Any way, he is putting out the razzle dazzle. He stated that the timing chain had broken, it had dropped (bent) a valve, and he had replaced all the valves. He said it was because the prior owner had not have the chain serviced at 100,000 miles.

Weeeeeelll, I have the same 4.6L V8 in my truck, earlier version, some differences, but it has a chain, and I mentioned that my understanding was that a chain did not require servicing or replacement (as a maintenance item), and that I thought that in the rare event a chain broke, it would not drop a valve.

He said that was true for my engine, but not for later models of the same engine, and that regular servicing of the chain was recommended.

I looked it up, and in 2005 Ford introduced a 3 valve SOHC version of this engine (mine is a 2 valve). So there's an extra valve.

BUT I have no found any discussion of the chain being a maintenance.


Bottom line, was he full of BS, or is this something I need to know?

My 08 civic has 220k, valve lash adjusted twice now, chain is still tight with very little lash.

 

[Chatsworth]

I have a 2003 work truck I drive with a 4.6 that just crossed over 240,000 with original timing chain..

 

[roundhouse]

The cam phasers on the 4.6 and 5.4 can be a problem
I’d be worried about a motor that had new valves and the heads off without any bottom end rebuild

A 2002 expy should be in the $1,500-1800 range and if it has had issues it should be less than that.
Check the car fax and see how many owners it’s had

Last year I bought a 06 expy 4wd limited with every available option from the original owner with 88k miles for $4,000 since that’s what the Buick dealer and car max offered him for it

just be glad you don’t have a Nissan, a coworker with a ‘16 infinity QX80 same as the Nissan armada and it Is throwing codes for the timing chain or belt or whatever it’s got
And his mechanic told him it’s gonna be $5,500 to fix so they should trade it soon.