How common is guide issue?

[Roont]

I know this is an annoying vague question, but the 99 SOHC Explorer I was given for free (due to no compression in #4) has a new owner. I have a used engine here for it and I am resealing it and doing the normal refresh I do on used engines (all gaskets, tune up items, water pump, hoses etc). This engine supposedly has 140k on it but who knows.

I am on a time crunch here and this truck needs to be in Colorado ASAP but since the engine is out, are the chains and guides worth doing on it or do they not normally go bad?

Customer is already on the top of their budget for this truck but they do trust my judgement but some research shows no issues with them at all then I see some information on here that makes me pause! I want to send this truck halfway across the country and know I did right by them, but also not murder their wallet if not necessary

 

[C420sailor]

Pull the valve covers and take a look down the chain tunnels. A borescope is great for this. If they look good, you don’t see any broken plastic, and you don’t find any in the pan, I would maybe install some new tensioners and call it good. If there’s broken plastic and/or the tensioners are fully extended, something is busted...

 

[410Fortune]

I would remove the timing cover and have a look see at the balance chain, main tensioner, and drivers side head tensioner assembly, all accessible through the front cover.

The 99 engine was better then 97 and 98, but still has a long way to go to be great.... If all nylong guides are still in place then I would:
remove balance shaft chain and tensioner
Upgrade main chain tensioner to the newer metal spring style (can get at autozone)
replace both front and rear timing chain tensioners, use FORD ONLY, not cloyes, not any other brand FORD TENSIONERS ONLY!!!!!!!!!!!!!!!!!!!!!!
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ at the dealer, don't trust online units they may be counterfeit if the price is too good to be true then it probably is

The continue on with your normal engine refresh

(Now some of us will use manual chain tensioners designed for a polaris rzr but that is another thread)

 

[Roont]

Awesome, thank you for all of the details!! Will definitely be doing this, even the Ford parts aren't too bad, will be sourcing tomorrow.

 

[donalds]

FORD TENSIONERS ONLY!!!!!!!!!!!!!!!!!!!!!!

I agree