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View Full Version : Hmm, Hard to believe this one..



Taylor86
03-01-2013, 12:49 PM
Have had a NO start problem for ahwile. After biting the bullet i took it to my mechanic, He states my Timing belt slipped. Can this happen sitting still?

Long story short my car was fine the day before no issues except a CEL for rear O2 sensor, the next day i had no start from in my garage.

Better than that if it did slip im sure it was when it was sitting as i drove and turned the key off right into my garage with no problems than the next day it just didnt turn over. He states "he thinks" there isn o damage to the valves..But dude he didnt listen to me, I would have heard a knocking or had a sign to show me, No signs so im sure if it truly did slip the valves are fine!

Seerlah
03-01-2013, 01:18 PM
Check compression. If you don't have compression, then you bent valves. Happened to me couple months back after trying to track down my no start issue forever. This was the damage. See the one intake valve bent on each cylinder? Engine was just fine, picked up a used head from nynoah, swapped a couple parts over from my old head that did not come with the replacement (he gave me a wickedly good deal), slapped it on and that was that. Car is running strong.

http://s11.postimage.org/ckx18496r/DSC03905.jpg

Mad Cow
03-01-2013, 04:00 PM
My timing belt skipped a tooth right after the car sat for 2 weeks, I think something fell between the crank gear and belt when I tried to start it. Even though the valves looked fine I had some ridiculous compression numbers after I timed it back up. (1 cylinder was at 90, 1 had 0 and the rest were around 50 psi)

Seerlah
03-02-2013, 02:29 AM
You have bent valves my friend. Looks can be deceiving. My issue was a peice of plastic getting caught between the crank gear and belt. Little piece of plastic cause so much damage.

Wraith600
03-02-2013, 11:22 AM
I have never seen an engine where timing slipped and it did not have damaged valves.

contrldsub
03-02-2013, 11:47 AM
I have never seen an engine where timing slipped and it did not have damaged valves.

i did. mine, it was almost 4 teeth off and still ran and no damage.

walky_talky20
03-02-2013, 12:50 PM
I have never seen an engine where timing slipped and it did not have damaged valves.
Really? What about non-interference engines! Lots of those, lol.

I've actually seen an engine that was would almost fire up, then lose compression, then almost fire, then lose compression - repeatedly as it was cranked. It would go out of time, then fix itself every few revolutions, then out of time again, etc. Turns out a mouse had made a nest in the t-belt and clogged some of the teeth causing this bizarre behavior. No damage to the valves at all (non-interference). Just cleaned out the cogs and put a new belt on it. Good as new.

audi-medic
03-03-2013, 09:50 AM
Really? What about non-interference engines! Lots of those, lol.

I've actually seen an engine that was would almost fire up, then lose compression, then almost fire, then lose compression - repeatedly as it was cranked. It would go out of time, then fix itself every few revolutions, then out of time again, etc. Turns out a mouse had made a nest in the t-belt and clogged some of the teeth causing this bizarre behavior. No damage to the valves at all (non-interference). Just cleaned out the cogs and put a new belt on it. Good as new.

Ok most wont believe this but when I bought my car it was nearly dead it was about 30miles from my house so I decided to drive it home, what I didn't see was the oil light on due to cluster depixelation, so I'm driving on the free way and I start loosing power , pull to the side car idles and dies, try to restart, starts dies in two min, doesn't start anymore, have it towed.

The outcome, the engine was oil deprived to the point where the camshaft sprocket snapped and by the looks of things the sprocket was spinning for a while,

Fixed the sprocket and the low oil pressure problem, engine is still good, pulls good, no bent valves

Wraith600
03-04-2013, 08:36 PM
OK I should have clarified that most that I see are motorcycle high RPM interference engines. I get the non interference obviously, LOL. Had a buddy that brought in his zx6r in after trying a start with the exhaust cam way out and they were all bent. Bike didn't even run for more than a minute. Maybe because most times I get them, it's because the guy didn't set his timing right after removing a cam. Maybe a slip is more likely you get lucky.

If you took those motors apart, removed the valves and measured run out you think there wouldn't be any at all? I would love to stay hopeful, but I guess it would always be nagging at me that they got smacked and would drive me nuts.

Taylor86
03-06-2013, 04:43 PM
Well turns out i bent some valves. I ended up spending about 2,450 getting everything fixed plus some extras i wanted done like

Heater core flush (heat only worked half the time)
rear o2 sensor (he pretty much threw that in) for everything im getting done.
Both heads sent to machine shop
TB kit
fuel flter
Oil change/oil filter
some random seals throughout the car.

He worked with me on labor but im happy in the end should have my car in about a week.

Seerlah
03-06-2013, 05:12 PM
You have a 2.8?

Taylor86
03-06-2013, 07:35 PM
Yep 2.8L v6 AWDQM