Lost a Timing Chain while starting up

I'm a new Member , I spent all day yesterday determining
what was up with my 450 SL 1980 merc,

I've had it for 20 years and I've replaced trans radi fuel pump etc.

Just put a new soft top car is cherry. I washed it Sunday,
put it back into my garage and an hour later I went to start it and

lord have mercy Great rattle bag lifter topend sound.
I stopped cause it wouldn't turn over, i thought it wasn't getting
fuel from the fuel pump so I banged the rear where it is and started it again , this time it started and bang it started,

thinking it would calm down I let it idle for about thirty seconds untill I realized this is a sound I 'm not familiar with.

Looked under hood next to power steering pully there was a crack in my valve cover.

Doh how could a timing chain go?

I got a estamite from my mechanic for valve job and chain and guides head gasket the works $2300 total for everything?

I'm not sure if I need all the valves done yet but I figure it's probably what's need.
Is that a good price? since I wasnt driving it could it be cheaper?

thanks for any input , nice to be a member.
Maybe being a member I won't have these things happen again to me.

That's not too bad for repairing a snapped chain on a V-8 model and fixing the equivalent damage.

How many miles did this car have, by the way? The only way you could have prevented this is by changing it out beforehand, at the recommended mileage.

-Sam

The car had app 100,000 and never was running smoother
thanks for input on price, I still can't believe to get my car running again it's gonna cost that much.

[MikeTangas]

Well, you're looking at a chain and guides, plus a at least a cam shaft or towers, several valves (minimum), pulling the heads for the valve work. It all adds up, and $2300 is a pretty fair price for the job.

What caused it?? Well, you are at the 100K mark, that in it self shouldn't be the cause, but 20 years on the plastic chain guides is a lot. The plastic gets brittle with heat and age, when new the guides are white, turning to an amber as they age. Really bad ones will get to a beer bottle brown (if they don't break first). Chances are one of the guides broke under start-up and a chunk of the plastic bound up the chain, breaking it. Once that happened, the valves started beating into the piston tops (or vice versa), and since these are interferance engines, the pistons drove the valves back upward into the cam, likely breaking it or the towers.

Well the car used to run always in the red untill I finally got a new radiator, I'm sure your much wiser than me. I just put new power sterring couplings and steering resovoiur new motor mounts, tires. top, so I am hoping I will be able to enjoy my car
for the summer.

Thanks Mike for your time and input! the $2300.00 pays for the whole thing p and L he didn't mention the cam though

[Gilly]

Problem could also have been caused by the chain tensioner, make sure it gets replaced with the other work.
Gilly

Man you guys are great, thanks for the input and for intelligent
options and future work on my car. I plan on keeping it
for a long time.

[MikeTangas]

Thanks for catching my omission Gilly. It's been nagging me all evening, I knew I forgot something but couldn't put my finger on it. Most definitely, new tensioner too.

I only mentioned a broken cam because every thrown chain I've seen on a V-8 has destroyed the left cam or cam towers, so I expect a cam will be in order too. I could be wrong though.