Rattle at idle

[Mike 92 XLT]

For the past 4000 or so miles (and about six months), I've been hearing an intermittant rattle/diesel-like sound at idle. I mentioned it to my mechanic at the 127,500 mile service, and he said that the only thing he found was that my radiator fan was cracked. Replaced it with a new one (only $30 through Ford Parts Network--thanks Torrie!), but the rattle is still there. It's only at idle, pretty intermittant with no pattern, and is not present while driving. Other than that, nothing else has changed (gas mileage, drivability, no check engine light, etc.). Any ideas?

peace

Mike

 

[yob_yeknom]

Mine is beginning to develop a rattle/knocking sound at idle. I believe it is the timing chain. My Dakota did the exact same thing and it was the timing chain. It had almost 1" total play in it!
A cheap way to find where it's coming from:
take a long rubber hose (around 4') that is about 1/2" thick
stick one end next to your ear and touch parts of the engine with the other end
it works like a stethoscope
just make sure to watch out for the fan blade and serpentine belt while doing this!

 

[Mike 92 XLT]

Any idea how much this is gonna cost?

peace

Mike

 

[yob_yeknom]

Have you figured out if it is the timing chain or not?

 

[Mike 92 XLT]

Haven't had any time yet to check it out. End of the year work is killing me here at school. I'll definitely do it soon though, because I'm driving 2500 miles back to CA at the end of April and I figure I should get this fixed before then. The good news is that a new timing chain is only $25 at FPN. Do you remember how much labor was involved with changing the one in your Dakota?

peace

Mike

 

[yob_yeknom]

It seems that changing the one on my Explorer will be almost the exact same thing: basically everything on the front of the engine has to come off or moved aside to make it easy to access the timing cover. (A/C compressor, water pump, etc...) The coolant system has to be drained (to remove water pump) and it will probably be easier if I just remove the radiator too. I guess I'll wait a while for this repair.
Whenever you do it, make sure you have a couple of days to get it done. It took a long time on my Dakota and was not fun. Post on how the repair went when you decide to do it. (if that ends up being the problem)

 

[Mike 92 XLT]

Ugh...that's what I was afraid of. I don't have the time or the tools or a place here in MI to do that kind of work, so I'd have to take it to my mechanic. I think I'll just wait until the summer to do it, if that ends up being the problem. Thanks for all your help, and I'll let you know how it goes.

peace

Mike

 

[COMMOCOZY]

I am guessing this is what is called PISTON SLAP... I had the same noise on my 96 Chevy Beretta. The block and pistons were made of 2 different types of metal ( I think ) they expanded at different rates. I have this same thing with my 98. I don't think it is anything to worry about.