Are there physical signs timing has already been done?
 

Hi all! I bought a 2004 Ford F-150 supercrew 5.4 Triton with 160k a few months ago from a private dealer. According to the paperwork that came with the vehicle, they had the timing belt changed, as well as a few other repairs (spark plugs, exhaust/valve cover gaskets). Since owning it, it has given me every sign that the cam phasers were not changed and I believe it’s possible that the timing chain wasn’t done right, if at all, as it is jumping teeth!! The whole engine shudders, clanks, and stalls. I’ve been in touch with the mechanic that did the work on it for the seller since there have been several things since purchasing it that have needed repair (Exhaust pipe rusted through and broke, VCT Solenoids, and MAF sensor).. totaling 1k on a 8k truck within 3 months of owning it.. now the ticking of the cam phasers, lost compression, misfires, clanking on deceleration, and a constant clank-clank from the front of the timing cover.. The mechanic has given me the run-around that I need a silencer for the phasers and just seems very reluctant to look further into it which is understandable. According to him, he didn’t use ford parts but says he changed the phasers.. I’d want to have my hands washed clean of this too if I were him so I don’t blame him for not wanting to look into it.. so, I’m about to tear into the engine and start what I think may be a grueling job changing the timing chain, tensioners, oil pump, and phasers.
I’m curious if there are any things I can look for that would indicate it’s been changed already BEFORE I start tearing into it. Like broken clips, or things that otherwise would say it’s an aftermarket part or something? Something tells me it wasn’t even done and I bought a lemon from some very clever car dealers..
I love the truck and believe I can repair it myself with help from YouTube, but any tips on signs it’s been changed other than what the stock timing chain looks like under the cover would be great.
Thanks!