I just bought a decent 1984 toyota pickup 22re with 376k miles on. When I bought it, I could hear that there was a slight whur in the engine which I deduced to being the timing chain rubbing up on the housing of the timing chain cover. I didn't strike it as a massive issue if I fixed it as soon as possible, but I didn't have the chance. The chain broke on me a couple days later in a Walmart parking lot when I tried to start it, luckily it started and immediately broke and died. When I stripped everything off to uncover the timing chain it was definitely broken but just laying in the bottom loosely wrapped around the bottom sprocket, not bound up, didn't cause any extra damage on anything that I saw, replaced the timing chain, tensioner, guides, sprockets, oil pump, water pump, oil pump screen in oil pan, spark plugs, belts. Anyways, once I struggle ˟˟˟˟ed with replacing the timing chain and making sure that the timing was on point with TDC, I could get the truck to start after adjusting the distributor cap, but it was running really rough and rocking, I remembered while checking TDC and checking the rocker arms that the 4th cylinder exhaust and ignition arms had way too much play in them regardless of which cycle it was on. So I did a leak down test as well as a compression test. I checked my first cylinder just to confirm that it was reading, and it read around 140 psi which from what I've read is about 15-20 psi less than stock, which also made sense from what I've read about high mileage motors over time wearing it down to a lower compression rate. My 4th cylinder didn't read anything at all, mean literally didn't pickup on my compression test. So this is my work vehicle and it has now been down for 2 weeks. My boss just says to do a valve job on, but multiple mechanics have told me that just replacing a valve or even all 4 of them for that matter will only make the piston rings go and a bunch of other things in the block that are worn down. So I have mechanics that are trying to tell me to but a new engine and put it in, and my boss ( who is paying for it as a loan) who is saying ˟˟˟˟ them, just do the valves. The engine rebuild project would cost around $3,000- $3,500 taking it to a shop,, whereas the valve job would only cost about $1,000 if I did it myself. But I don't want to put that much more money into it, I bought it for $4,000. If I rebuilt the engine there is no way I would ever get my money back on the vehicle if I tried to sell it in the future. Please help me out I am on a time crunch and can't really trust these mechanics or my boss at the moment, been tugged around too much already.