Timing chain

i have a 1987 lin. towne 302 the timing chain broke in my driveway, had it towed to my long time mechanic. before when the engine ran at slow idle i could hear a very faint knock. but it wasn’t even noticeably. since the timing chain was put in it’s more noticeably. at low idle?could putting a new timing chain cause this? it only happens when the engine is fully warm and when the idle is low otherwise you don’t hear it. my mechanic says it would not be worth it and i agree. i just want to hear a little feedback thanks

If you get no response here, check in at www.crownvic.net in the 5.0 L forum. What do you mean by, “my mechanic says it would not be worth it…”

The time to fix it was when the timing chain was out. There are a number of things that could make the knock but the mist likely cause would be a worn woodruff key in the lower timing gear. The harmonic balancer or its key would be the next most suspect.

Eventually the culprit will sheer and it will have to be addressed then, but that might not be for a long time. Its possible that you may get rid of the car for other reasons before that happens so it may not be worth repairing right now.

Geez! Where are all the people that claim timing chains last the life of the engine?


thanks for the comeback—he says he would have to lift engine out , no way

thanks i will mention it to him and your right next year it will go but boy does it bug me when i come to a light and i hear mr. knock, the car is in beautiful shape it just cheapens it.

yep i keep reading on car talk about these timing chains. i think i gave myself the Italian horns. i’m so careful with this car don’t push it, drive the speed limit on express ways and what do i get ? the chain breaks in my driveway. i guess i’m lucky it happen there? the car has 111,000 mi. on it.by the way the oil light has been flicker on and off even before the chain broke, step on the gas slightly and it goes off.

Actually, golfnut, the 302s of that vintae were notorious for jumping time. By 120k on automatics and by 80k on manuals they jumped, usually on start-up. The chains were laminated “silent chains” and the cam gears were plastic.

You may get some added miles from a dose of one of the oil thickeners, STP being the most notable. The OIL lignt at idle in conjunction with the rattle are an ominous combination.

Timing chains last the life of the engine. There. Do you feel better?

They did, when the life of an engine was about 100,000 miles.

Seriously, I like to replace my (overhead cam) timing chains in the 200-250K mile range.