I have got a '06 XLT Explorer (160k miles), engine code "E", that has broken the front Left timing chain. This happened when the engine was running and the broken chain made a small hole in the TC cover. Of course when this happened, the engine stopped. I am just trying to figure out what the damage is internally and about what it will cost to do this repair myself. Ford dealer wants $7,000 to repair. The car is not worth that.
I have been doing a bunch of reading here and it sounds like this is a pretty common problem. I am concerned that since this is an interference engine (from what if have read), there may be a bent valve or damaged piston... etc. Engine had not been making any noise, so I can only assume that the rear timing chain and cassette is good.

I was thinking that I could do a compression test on all the cylinders, that would tell me if I have any internal damage. But, to do that, I will have to replace the broken timing chain and then do the compression test. If it fails that, then I know the head will have to come off. If it passed the test, I would just replace the front chain and cassette, replace the damaged cover and keep driving it.

If I have to, I will pull the engine and replace the rear chain/cassette and the front chains. I just don't want to do any unnecessary work.

What do you guys think? Is this a good approach to repairing this, or is there something that I am missing? Is there a step-by-step guide that shows how to do this? What about a Ford Service Manual for this engine, is there one out there I can look at?

Thanks

 

I just saw an article here that says that this engine is NOT an interference engine.

Can someone confirm that it is or isnt an "interference" enigne....i.e. will the piston crash into the valve if the timing chain breaks?

Rather than a compression test, I was thinking I could do a "leak-down test". I could turn the cam until I get both valves closed. this would tell me if there is any internal damage in the engine.

Thanks

 

I can point to two things that say it is an interference motor. First is (was) an ad in craiglist for an Explorer with the SOHC motor. I tried, but can't find the ad. The seller had torn it apart because the timing chain went and he said the valves were bent. I don't remember the year exactly, but it was between '97 and '01.

The second is this: Is 4.0L SOHC V6 an Non-Interference Engine? - Ford Explorer and Ranger Forums "Serious Explorations"®

Not sure if that info still applies to your 2006.

 

Here's the ad I was referring to: 1998 Ford Explorer 4x4 XLT 4.OL

So, two guys who have had timing chain issues and bent valves. That's the extent of my knowledge on this.

 

Consider your motor junk.

Take all the intake and electrical off it, and swap in almost any 4.0 SOHC motor, even Mustang engines. The site listed above has a very long thread on this, with multiple users swapping later motors.

If that sounds good, I will search out that thread and post a link.