So I was driving my '87 325is down the freeway when I lose all power. The car was in gear when the timing belt snapped and stayed in gear for a good five seconds before I put in neutral. I'm a noob to this but i'm pretty sure i'm looking at a couple bent valves. I am right? Lol Also if so valves expensive? Trying to figure out if it's worth fixing or getting new used head or swap.
Announcement
Collapse
No announcement yet.
Timing belt snapped while driving, bad???
Collapse
X
-
Pull the head before you try to decide anything, or at very least the valve cover to inspect damage. If more than just the rockers are damaged expect to need an engine as it takes some serious piston-valve contact to destroy the rocker shadt retainers.
Example, my newest car had a blown m20b25 timing belt
note the 1st and 3rd head bolt platforms are broken over the rockers
Again, but a complete picture. (sorry the picture is upside down) note how many broken rockers and parts of the head itself on the intake side
The result on the bottom end, every piston was damaged almost identically.
Good luck!1990 332i, 4 door
2008 KTM 990 Superduke
2018 Golf R, 6spd manual (Pending delivery)
2017 Mazda CX-5 GT
2007 Z4M Coupe - Sold to very nice people
Comment
-
Originally posted by LagunaVert View PostHeres what i found when my belt snapped at idle...
Broken valve stem punched a bullet hole through piston numero uno.(With bottle cap for size reference) Replaced head, piston, etc. Been running strong ever since.
Best of luck to ya.sigpic
Comment
-
Curious about the mileage or years or both on your belts when they failed.
I'm past due for time ( year 5.5) but a mere 17,000 on mine. I know I'm dancing with the devil putting any more wear before replacing mine. so just curious about when yours failed. Saving up funds since my 24 year- old radiator has to go, along with lower hose, tensioner, water pump, thermostat, - all on year 10 at least. I'd love to say I had the chops to do it all myself, but alas I'm a bit intimidated. I've pulled-swapped subaru motors, swapped carbs and intakes back in the the day. But now I'm just chickenshit I'll fuck it up."just love those little tanky inline 6's"
Comment
-
The car from those pictures was picked up with the motor already blown as a project car, the sticker on the shock tower says belt was replaced at 213,000km. The car now has 214,000. When I pulled off the timing covers I found the tensioner locked in the fully released position so basically the P/O fucked up. The repair is not actually that bad if you pay close attention to the steps and a bentley is a huge help for first time1990 332i, 4 door
2008 KTM 990 Superduke
2018 Golf R, 6spd manual (Pending delivery)
2017 Mazda CX-5 GT
2007 Z4M Coupe - Sold to very nice people
Comment
-
Originally posted by GUERONASTY View PostSo I was driving my '87 325is down the freeway when I lose all power. The car was in gear when the timing belt snapped and stayed in gear for a good five seconds before I put in neutral. I'm a noob to this but i'm pretty sure i'm looking at a couple bent valves. I am right? Lol Also if so valves expensive? Trying to figure out if it's worth fixing or getting new used head or swap.
Comment
-
Originally posted by Massimo View PostSore bottle cap and thought WTF?1974.5 Jensen Healey : 2003 330i/5
Comment
-
Originally posted by Vivek View PostJust get a new head if not a new engine. Trust me.
Originally posted by MR 325 View PostBest case scenario you'll still have a few bent valves. The only way to do it right is to remove the head, pressure test it, check all parts, resurface and rebuild.
Comment
-
I didn't listen to people when I bought mine...also being a chip ass...my belt popped at 5000 rpms...not good.
Wasn't bad though. Bought a used head and all the parta to replace it. Only working on it once a week and got it done...maybe 10 hours...first time tearing into a motor and had some dumb moments. Been running strong for a year now and I am not being a cheap ass with it anymore. ;)1985 325e - a cheap work in progress
http://myquest4happiness.blogspot.com/
Comment
Comment