I am so pissed!
I have been preparing the time location and money to remove the timing chain guides due to the rattling under the valve cover. I have read forums for a long time now, and even had 2 different chain removal guides printed out.
Unfortunately, my dumb *** waited too long. Monday night... I was driving southbound on I-35, and all of the sudden the engine seemed to lose power. I didn't hear any loud clanking or knocking or grinding, but then again.... I was listening to my stereo prettly loudly. At any rate... the car would no longer accel. As soon as this happened... I knew what it must have been.
Sure enough, the upper timing chain guide broke off it's mounting bracket and was launched along the pathway of the counterclockwise moving timing chain. Well, that little metal rectangular piece couldn't curve along the exhast cam sprocket so it bent and wedged with so much force that the sprocket on the exhaust cam snapped off and also cracked the valve cover.
Amazingly, the upper timing chain is still intact. Now.... I guess what I need to find out is whether or not this is salvagable. I found a used exhaust camshaft for $50, but then there runs the problem with the valves being bent.
Now, the exhaust camshaft valves all seem to be closed.... (full upright position). Could this be because they are bent?
Somebody gimme some input on this deal because I am so ashamed!
What do I do to save my beeotch?
93 240sx s13 KA24DE timing chaing guide broke inside motor
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sil80drifter
- Posts: 1313
- Joined: Sun Aug 18, 2002 5:53 am
- Car: 1990 240SX Hatch
When the valves are bent, they usually will NOT close all the way when they are supposed to. So in other words, when you take the exhaust cam off, they are ALL supposed be closed as there is nothing pressing them down anymore. Take off the exhaust manifold and check for visible gaps, and feel around with your finger if you can detect a valve that's not all the way shut.
The best way to check would be to take the head off, but I don't know if you are in a position to do that.
sil80
The best way to check would be to take the head off, but I don't know if you are in a position to do that.
sil80
Re: 93 240sx s13 KA24DE timing chaing guide broke inside motor (sickamaya)
Remove the two cams and run a leakdown test on every cylinder. Listen for any possible hissing on the exhaust and intake side which would indicate possible bent valves. On the leakdown test, if everything is OK, you should see no more then 5% leakage. 3 to 4% is ideal.
Since there was a major problem with the upper timing chain assembly, you should replace the upper chain and the cam sprockets. The lower chain assembly should also be inspected at this time.
Since there was a major problem with the upper timing chain assembly, you should replace the upper chain and the cam sprockets. The lower chain assembly should also be inspected at this time.
Re: 93 240sx s13 KA24DE timing chaing guide broke inside motor (sickamaya)
I appreciate you both responding....
Needless to say I have been stressing out very much over this event.
My mechanic is out of town for the weekend so I won't be able to do any testing until that time.
I had spoken to a couple of other mechanics that I feel are trustworthy opinions regarding this sensitive matter, and both of them are strongly supporting the idea that it is highly probable that the valves are bent.
See the thing is.... the mechanic that is helping me work on the car has it at his shop about 40 miles from where I live. I broke down on the highway so getting a tow would have been about 200 bucks. He went and towed it for me for no cost... just some labor exchange, for I agreed to clean up his computer problems. Due to the fact that I am not actually paying much for labor in this situation, I am hesitant to trust that his opinion or diagnosis is thorough or strategic. For in the general situation a mechanic is strongly influenced by the customer's willingness to pay cash for labor.... so a mechanic would eat this type of job up, it being one that may require long hours and dedication (such as removing the head).
Here's what he said. We went ahead and removed the Exhaust camshaft... as well *** the timing chain guides... (what's left of the top one anyway). The sprocket is still bolted to the camshaft end that broke from the main camshaft rod. Before removing the sprocket cover I was suggestive that we would rotate the crank pulley to align with the TDC pin, that way we could calibrate specifically the markings of the sprocket and the new camshaft starting point.He stated that he was hesitant to do this because it was possible that the valves would get bent if we rolled it over now. Isn't it a little late for that?I figure the damn thing is already way out of time, but I just couldn't understand what he was saying. Since I'm brand spanking new at all of this, I have no choice but to let him make the call.
Also, the sprocket that broke off of the camshaft seems to have chipped away at part of the head and jagged up the concave seating point where the camshaft sits and revolves by the sprocket turning.
Here are some pics of what I'm talking about.... Please look and see what you think. I need to make a decision about what to do. He is suggesting for me to just go get a new camshaft.... where I found one used on a salvaged KA24DE engine here in the city for 50 bucks. The dealership says they are 285 bucks new. So this mechanic says in order to see if the valves are bent, we should get another exhaust camshaft.... but it back where the broken one was, and then and only then try to turn the engine over and see if the valves are bent.
He doesn't seem concerned with the metal pieces that are chipped and jagged from the head..... and as long as I find them in the oil pan... I guess I'm not either. He said that he could smooth out the jagged grove where the camshaft sits.
Problem here is.... the other two mechanics that I only spoke to on the phone are both very pessmistic about the valve conditon of the motor, and one of them even told me what to do to test the valves without having to buy any parts. He said to remove the other camshaft and sprocket.... (timing doesn't matter at this point because it's impossible for it not to be way out of time as it is).... once that camshaft is removed... do a compression test just like you suggested. He said that small hissing would be normal.... but if the valves are bent... (and he thinks all 16 are)... then there will be a huge stream of compressed air shooting out of them... (both exhaust and intake).
I love that F***ing car so much.... and I'm truly saddened with defeat knowing that I had printed out all the walktroughs and guides for timing chain removal.... but, mainly intimidated with the sensitivity of the Engine being the heart of the car, and I'm no surgeon. I think the part where it says to align at TDC on crank pulley and then mark the distributor location.... and don't allow it to rotate once it's removed or you're in for hell to get it back in time..... that's what really intimidated me. At this point I just want to be realistic about what I'm up against.
After yesterday I accepted that it was dead, and I wasn't going to be hearing that motor hum ever again. But after reading these two replies... I get the sense that there is still hope, may it only be a glimmer.
I don't have money for a new car.... so figuring out what I'm up against is crucial.
Sorry for the rambling... but these damn forums have been so biblical to me.Even more so now that I have been reading them since I bought the car in August of '05 and found the rattle to exist under the valve cover and found the culprit here in these forums without ever having to remove a bolt.
I've known about it for that long.... and truth be told.... I believe I would have done it as soon as school was out. Last day of school is April 28th, timing chain guide broke April 17th.
So my confidence and appreciation in all of you who take the time to read.... and respond to these words of deperation and shame is very, very real.
Thanks again, and here are the pics of the motor. If you see where both the E-Camshaft and the timing chain guide were removed you can see where there is some metal pieces missing, especially the golden chunk exposing the chain. What are your thoughts on this?
Needless to say I have been stressing out very much over this event.
My mechanic is out of town for the weekend so I won't be able to do any testing until that time.
I had spoken to a couple of other mechanics that I feel are trustworthy opinions regarding this sensitive matter, and both of them are strongly supporting the idea that it is highly probable that the valves are bent.
See the thing is.... the mechanic that is helping me work on the car has it at his shop about 40 miles from where I live. I broke down on the highway so getting a tow would have been about 200 bucks. He went and towed it for me for no cost... just some labor exchange, for I agreed to clean up his computer problems. Due to the fact that I am not actually paying much for labor in this situation, I am hesitant to trust that his opinion or diagnosis is thorough or strategic. For in the general situation a mechanic is strongly influenced by the customer's willingness to pay cash for labor.... so a mechanic would eat this type of job up, it being one that may require long hours and dedication (such as removing the head).
Here's what he said. We went ahead and removed the Exhaust camshaft... as well *** the timing chain guides... (what's left of the top one anyway). The sprocket is still bolted to the camshaft end that broke from the main camshaft rod. Before removing the sprocket cover I was suggestive that we would rotate the crank pulley to align with the TDC pin, that way we could calibrate specifically the markings of the sprocket and the new camshaft starting point.He stated that he was hesitant to do this because it was possible that the valves would get bent if we rolled it over now. Isn't it a little late for that?I figure the damn thing is already way out of time, but I just couldn't understand what he was saying. Since I'm brand spanking new at all of this, I have no choice but to let him make the call.
Also, the sprocket that broke off of the camshaft seems to have chipped away at part of the head and jagged up the concave seating point where the camshaft sits and revolves by the sprocket turning.
Here are some pics of what I'm talking about.... Please look and see what you think. I need to make a decision about what to do. He is suggesting for me to just go get a new camshaft.... where I found one used on a salvaged KA24DE engine here in the city for 50 bucks. The dealership says they are 285 bucks new. So this mechanic says in order to see if the valves are bent, we should get another exhaust camshaft.... but it back where the broken one was, and then and only then try to turn the engine over and see if the valves are bent.
He doesn't seem concerned with the metal pieces that are chipped and jagged from the head..... and as long as I find them in the oil pan... I guess I'm not either. He said that he could smooth out the jagged grove where the camshaft sits.
Problem here is.... the other two mechanics that I only spoke to on the phone are both very pessmistic about the valve conditon of the motor, and one of them even told me what to do to test the valves without having to buy any parts. He said to remove the other camshaft and sprocket.... (timing doesn't matter at this point because it's impossible for it not to be way out of time as it is).... once that camshaft is removed... do a compression test just like you suggested. He said that small hissing would be normal.... but if the valves are bent... (and he thinks all 16 are)... then there will be a huge stream of compressed air shooting out of them... (both exhaust and intake).
I love that F***ing car so much.... and I'm truly saddened with defeat knowing that I had printed out all the walktroughs and guides for timing chain removal.... but, mainly intimidated with the sensitivity of the Engine being the heart of the car, and I'm no surgeon. I think the part where it says to align at TDC on crank pulley and then mark the distributor location.... and don't allow it to rotate once it's removed or you're in for hell to get it back in time..... that's what really intimidated me. At this point I just want to be realistic about what I'm up against.
After yesterday I accepted that it was dead, and I wasn't going to be hearing that motor hum ever again. But after reading these two replies... I get the sense that there is still hope, may it only be a glimmer.
I don't have money for a new car.... so figuring out what I'm up against is crucial.
Sorry for the rambling... but these damn forums have been so biblical to me.Even more so now that I have been reading them since I bought the car in August of '05 and found the rattle to exist under the valve cover and found the culprit here in these forums without ever having to remove a bolt.
I've known about it for that long.... and truth be told.... I believe I would have done it as soon as school was out. Last day of school is April 28th, timing chain guide broke April 17th.
So my confidence and appreciation in all of you who take the time to read.... and respond to these words of deperation and shame is very, very real.
Thanks again, and here are the pics of the motor. If you see where both the E-Camshaft and the timing chain guide were removed you can see where there is some metal pieces missing, especially the golden chunk exposing the chain. What are your thoughts on this?
One more picture
Here is another picture.
Can you tell by looking at this if the valves appear to be completely closed?
Can you tell by looking at this if the valves appear to be completely closed?
Re: One more picture (sickamaya)
In pic #1, the front journal saddle thrust surface looks rough. If you can smooth that out, you might be OK.
In pic #2, the height of the valves can't be determined.
A compression test is not the same as a leakdown. With both cams removed, do a leakdown test not a compression test. Your mechanic will know.
As far as setting up the timing chain, it's not that bad at all; very straight forward. You first setup the cam timing then you go back and setup the ignition distributor; two separate procedures.
Modified by rogoman at 9:13 PM 4/21/2006
In pic #2, the height of the valves can't be determined.
A compression test is not the same as a leakdown. With both cams removed, do a leakdown test not a compression test. Your mechanic will know.
As far as setting up the timing chain, it's not that bad at all; very straight forward. You first setup the cam timing then you go back and setup the ignition distributor; two separate procedures.
Modified by rogoman at 9:13 PM 4/21/2006