Anyone's timing belt snapped and bent valves?

ok

I'm not amused......

the head finally came off today..... these do NOT look bent (to me). but I'll have to check it out a bit more... (and take better pics)

1268766030.jpg

1268766027.jpg

1268766023.jpg



all that's left on the pistons is a ton of carbon.

oh but let's play "spot the foreign object" what does not belong here?
1268766033.jpg


lol.
 
Well, I think that this finally lays the question to rest - our motors are NON-INTERFERENCE!!!
 
So (in retrospect) just swapping the new belt on and firin' 'er up was the correct answer...
 
^^ we'll find out....... a few of the valves have some carbon knocked off of them, but nothing serious..

all the pistons are (definitely by a machine) relief cut for the valves..... albeit a crap load of loose carbon sitting on the top, it seems totally fine.

I guess we'll find out though..... I'm gonna clean the head up and work each individual valve to check for any play at all, that would indicate to me if it indeed is bent or not...... because certain people (IE shop teacher) are STILL convinced they were bent.
 
OK thought I'd give another update.....

the valves ARE bent. just a TINY TINY bit.... nothing a screwdriver can't fix. lol.
 
still got some more crappy cell phone pics........ but the idea is I used a really fine air nozzle (IE the awesome blue fuel pump looking air nozzle) and put it on full blast, and followed around each valve. a LITTLE bit of air came out through each port, but only around half of each valve did it do so.
 
But that would indicate valve seals - not bent valve stems...

And remember - when you have the full force of the ignition - the force would help drive the valves even more seated... So they still may be 'good'.
 
ok... for the record.. the BOOK says the engine is a NON interference engine here is the link... clicky clicky

as to the valves being shut... UNLESS your cam is OUT of the car.... atleast half of them are still open at one point or another.. I have snapped a timing belt ( too much boost, and blew the bottem end apart)
 
mikebontoft said:
OK thought I'd give another update.....

the valves ARE bent. just a TINY TINY bit.... nothing a screwdriver can't fix. lol.
Click to expand...

did you use a micrometer to tell if they are off? ( being the measurements along the outter portion? your valve seals might be gone... you can get grinding putty from auto zone and a suction cup and re grind them to fit with out spending 75 bucks... ( i just rebuilt a head after porting and polishing it and having it bench tested.
 
Essentially, what I'm thinking is that they either make non-interference motors or interference motors - nothing in between. This means that if your valves are not f-ed up beyond all belief, then they didn't get any damage from the pistons (if a moving piston hits your valve, it's not gonna bend it just a tiny tiny bit).

It really sounds like you've got some bad valve seals or something. Any chance you could put the head back on and do a leak-down test?
 
I'd um, have to go find the head gasket I chucked into the sky........ but I already DID a leakdown test (albeit not measured). it sure seems to me like the seals are bad. How would I go about measuring them anyway?

I'm assuming carbon probably got in between the seal and valve, and munched up the seals maybe?
 
Umm... pistons pumping up and down at 4k rpms would **** those valves. Not just bend it a teeny bit. +1 on the seals. And with 189k? You coulda just assumed that before any of this even happened. Especially if it was so 'well maintained' it had the stock T belt at almost 200k.

And when I had my head machined, I put it back together with a new T belt. My brother argued with me that the belt was properly timed at 180 degrees off. I argued a minute, but I knew it was non interference so I cranked it anyway to prove myself right.... No bent valves.

FS DE is non interference.
 
TheMazda said:
Umm... pistons pumping up and down at 4k rpms would **** those valves. Not just bend it a teeny bit. +1 on the seals. And with 189k? You coulda just assumed that before any of this even happened. Especially if it was so 'well maintained' it had the stock T belt at almost 200k.

And when I had my head machined, I put it back together with a new T belt. My brother argued with me that the belt was properly timed at 180 degrees off. I argued a minute, but I knew it was non interference so I cranked it anyway to prove myself right.... No bent valves.

FS DE is non interference.
Click to expand...

+1

lol... im still lookin for pics of my bent valves
 
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