Broken - Thoughts, opinions, stories, troubleshooting steps/results wanted please

[~5.0 Girl~]

Hey guys...

Background...

A few weeks ago I went to leave work for the day and started my car. I put it in 1st and started to pull away from the side of the road. Before I could even shift into 2nd the car made a really sudden and abrupt thud and completely shut off. Everything felt normal, seemed to have full power and then boom. I have never felt anything like it before and actually said outloud to myself - wtf that was wierd. So I contemplated whether I should try to start it or not and tried a few times. It wouldn't turn over... Luckily there were still some people around so I got it pushed into the shop. Our lead tech tinkered with it a bit and ended up pulling the distributor because the rotor wasn't turning... Eventually he got it to run and it would barely idle and it was knocking pretty badly. We reset the timing and took it for a road test. Although the car sounded like crap, it didn't seem to be losing power. I drove the car home (less than 10kms) and let it sit until I could get a chance to do an engine flush. The engine flush didn't do a thing to quiet the ticking noise. Fast forward to yesterday..... Get the car into the shop. Pulled off the intake and passenger side valve cover as that's where most of the noise was coming from. At first glance one of the lifters was stuck and looked to be the simple solution. Then we pulled off the rocker and quickly discovered that almost all of the push rods were visibly bent! It was late and we didn't have time to check the timing chain so....

WHAT HAS HAPPENED TO MY CAR?????

I'm thinking there could be an issue with the rocker/push rod combo - can they warp over time? Perhaps the timing chain jumped? I've had the car for over 7 years and never over-revved it when racing or otherwise????? Car has about 250 000 kms. Crane 1.7 roller rockers, I am unsure at this point if the rods are the original stock ones. Block has never been touched. Pretty recent oil pump, timing chain, water pump, etc due to a small coolant leak that I wanted to prevent from getting worse. Installed a new clutch, machined fly wheel and new starter (within last 30 000 kms or so).

I did a search in the forums but I would really, really appreciate your thoughts and educated opinions/experiences specific to my situation... This is my first time having my own motor apart. In the past I had friends do the work for me and I'd like to know what I am getting myself into before I get too deep.

Thanks guys!

 

[tmoss]

the way you worded this indicates the rockers were "bent" but I suspect it was the pushrods? I'd be checking the timing chain and sprockets first as it sounds like the valves may have been kissing some pistons.

 

[~5.0 Girl~]

Thanks T.... I was reading it over and edited that and just read your post after I saved the changes.

 

[tmoss]

make sure the lower sprocket did not shear the key off, or the upper sprocket for some sort of failure.

 

[Deleted member 87397]

Yeah, if you've never had issues with it before then I'd definitely check the timing setup. Not many other ways to bend valves, rods, and break rockers than a messed up timing chain/ gear. I'm surprised it ran for you after it initially died. You usually can't get them going again, so maybe the chain is in tact and it slipped a few teeth or you may have lost some gear teeth. That's all I can think of.

 

[7up.lmtd]

I would have to agree with the timing chain and gear check. Have seen this happen before. Everything is working and then everything dies. It was pretty typical on the Chevy 350's for a whil. In an effort to keep the engine quiet Chevy opted for nylon teeth on the Timing Gears. They tended to sheer off and drop teeth in the oil pan. You had to just pull the oil pan to verify that this was your problem as the teeth would be sitting there waiting for you.

With the rotor not turning and the bent and broken parts that usually points to timing chain or gears. Make sure you fully inspect and if your that far into it why not replace.

 

[~5.0 Girl~]

Thanks for your replies guys.

It's nice to read other people's opinions. I will definately be replacing whatever needs and should be once it's apart.

 

[tmoss]

and for our reward - we want to see some of those "topless' pics.....

Good luck!

 

[~5.0 Girl~]

So I pulled off the timing cover and the timing chain assembly was loose. It seems that when the timing chain was done about 2 years ago that it wasn't installed properly. I guess it came loose and shut the car off. I am very thankful that I was only in first gear and 30 feet from my shop. I do a tonne of highway driving and who knows what could have happened if the motor was under more load!

So now the question is should I go to a gear drive or just go with the same setup????

There's a topless pic of the car up there hahah

 

[BlownFiveLiter]

and for our reward - we want to see some of those "topless' pics.....

Good luck!

Dirty old man

Pick up a double roller timing chain to replace the broken one. FRPP, Cloyes, etc all make a quality part. If you bent pushrods, I'd venture to guess it was because valves hit the pistons pretty hard, so you might want to pull the heads and inspect the pistons and valves for damage, too. Having all the accessories off the engine already means that'll only add an hour or so to the total job, given that everything is in good shape with the heads. That's an area where I'd rather be safe than sorry, personally.

 

[~5.0 Girl~]

Thanks... I had a double roller chain installed when I did the oil pan/pump, etc, etc (that's what seems to have been the problem this time (not the chain but the moron who installed it). I was working for a Ford Dealer at the time so I got a wicked deal on the OEM parts. I was gonna go with the same chain but it will be installed properly this time.

I love the sound of gear drives but I'm not too educated as to the pros and cons.

 

[tmoss]

don't do the gear drive, you'll regret it. You can replace the timing gear and then do a hand crank for two crank rotations to see if there is any contact. If not, you could try a compression test followed by a leakdown check to see if any valves are bent.

 

[7up.lmtd]

I would have to agree with TMOSS and go with the Standard. If you planned on pumping some serious power into it then yes go with the upgrade. If it's your daily driver and you are planning on some minor upgrades/mods then standard chain will do.

Hope this helps.