bad cam shaft, pictures of damage

[oren hughbanks]

So I have been battling alot of valve train noise lately. Finally cracked into it today and see what's going on and noticed the end of the intake cam looked a little funny, and discolored. Popped off all my cam caps and found this.

I attribute the carnage to be from a bent cam, probably warped from being over heated. I bought the head used, but was immaculate, cleaned and recut from machine shop. Never had been run, still had the assembly lube in it. Sure wouldn't mind finding the guy who had sold it to me and taking that cam shaft to him, but it's my fault too for not checking the cam journal surfaces when I bought it.

You must be logged in to view this image or video.

You must be logged in to view this image or video.

You must be logged in to view this image or video.

 

[jimsgsx]

Thats rough. Lesson learned i am sure. Some people just out to make a quick buck.

 

[GST with PSI]

Just a thought, but the head could also be to blame. Machine shops have been known to make errors, and the cap bores could have easily been misaligned. In addition, if caps from another head were mixed up with the correct ones, that's much like what the camshaft would look like as a result.

Out of curiosity, were all the cam caps in order? Also, do all the numbers stamped on the caps look the same? I'm not implying you mixed them up or anything, but it's worth as check.

Lastly, even with screwed up journals, you can still check the camshaft to see if it's warped.

 

[oren hughbanks]

Ok here's where it gets weird guys. Yes the cam caps all looked to be in good order, arrows pointing the same way. On the exhaust cam side, the numbers started at 12 then counted up, but the intake side started at E24, then went up from there?? Quite weird.

Who knows what shop did the head, and I noticed it still had the 1g lifters too. But all the other cam surfaces looked perfect, clean as could be. It must not have been a shop familiar with 4gs[DOUBLEPOST=1416192970][/DOUBLEPOST]Sorry what I meant to say is that cylinder head was probably off another talon that overheated, and warped the cam too, and a shotty machine shop that never checked them. Here's a few more pics

You must be logged in to view this image or video.

You must be logged in to view this image or video.

 

[tmoney20g]

On the exhaust cam side, the numbers started at 12 then counted up, but the intake side started at E24, then went up from there?? Quite weird.

You must be logged in to view this image or video.

You must be logged in to view this image or video.

Um, Intake had the exhaust cam caps, and vice versa you said ? Did you mix that up or was that actually how they were on the head ?

That's not "12", that's I2, for intake #2 cap.

 

[oren hughbanks]

I also noticed quite a few rocker arms that had damaged tappett surfaces. Not sure what could cause this. Looks like the rocker arm body is cast steel, and almost like it has some pitting?

You must be logged in to view this image or video.

 

[GST with PSI]

Ok here's where it gets weird guys. Yes the cam caps all looked to be in good order, arrows pointing the same way. On the exhaust cam side, the numbers started at 12 then counted up, but the intake side started at E24, then went up from there?? Quite weird.

Yep, sounds like the caps were mixed up/wrong as I suggested. The caps on the intake cam should start with "I". Sounds like the exhaust and intake cam caps were swapped, which is why your cams and head are now destroyed.

You must be logged in to view this image or video.

You must be logged in to view this image or video.

 

[oren hughbanks]

Just went out to check, looks like they are in the right order. I made sure to place them in order as I took them off.

You can even see in the pic that material had been so smashed up in there it totally covered the oil port too, nowhere to be seen now,

 

[briansmith]

No. The caps where mixed up. That's not a 12. It's a I 2. As stated above there is no way the cam shaft warped mitsubishi used forged steel for those cam shafts. They where forged at over 2,200°

 

[GST with PSI]

Right, the caps can still be in the right order, but on the wrong side of the head. If the exhaust cam caps are in the intake side of the head, and vice versa they will destroy the camshaft. What you said in post #4 describes exactly that.

Set the caps on the head exactly like they were before they were removed. Then, take a picture and post it up.

 

[oren hughbanks]

Ok I'll do that when I get back out to the shop tomorrow.

Also where do I go from here? Am I looking a total loss here? Go ahead and break the news to me guys

 

[briansmith]

Yes I would like to see the numbers stamped on the caps[DOUBLEPOST=1416194865][/DOUBLEPOST]That head is trashed the cams have no bearings to replace so u can't line bore the head then install a stock cam clearances will be way off[DOUBLEPOST=1416195143][/DOUBLEPOST]Also the whole motor would need to be tore down. Cleaned and inspected all those aluminum shavings have now went into the pan. To the oil pump if it was mine I'd start over. Clean and inspect. If anything looked suspect or out of spec nows the time to replace. Total tear down. Even the turbo. If it's feed from the head most Def. If the ofh filter may have saved it. U hafta think. Anything that receives oil is now contaminated

 

[GST with PSI]

At a minimum, the cams and head are trash. How long and how many mile have you put on the car with this head installed?

Briansmith has it right, though. The whole motor has seen the aluminum shavings. See the oil flow here:

You must be logged in to view this image or video.

At this point, you have a few options. The first being, tear down the motor as Briansmith suggested. Honestly, that's the best, but most expensive and time/resource intensive option.

Or, throw on a new head and hope for the best. Of course, you'll want to change the oil, and flush the system as best you can. Maybe drop the oil pan, and pull the sump to clear out any debris that may be stuck. I mean, what do you have to lose? Every major engine component currently installed on the car that has already seen metal shavings will either fail as a result of the shavings...or not. Only time will tell. The only true remedy would be to remove and inspect every affected component; replacing where necessary.

You're in a really crappy situation, dude. I feel for you.

 

[briansmith]

I ran into similar problem with my spyder 6 bolt block 7 bolt head. Bought it on a fresh rebuild with 4 bent valves. Timing belt installed with cams 180° out removed the head when I got it home replaced valves. Cleaned everything up. Including soaking lifters flushing them 6 times. Went back to install head and thought hmmm. I need to inspect the Bottom end. Tore it out standed the block. And got to work. Lmao. Main bearings installed upside down. Oil pump trashed from the $10 ebay stub shaft. Balance shaft bearings not flipped to block off oil ports. Turbo had so much shaft play it have scored the comp housing and half the fins on the turbine side where missing trust me when I say everything on this car had been done incorrectly now 2 years later I'm finally in the home stretch of getting this car back to where it needs to be and everything is 100% correct best thing to do is tear it down and make sure that everything is in spec for another tour of duty I kno it's costly and time consuming but it's the best action to take. Keep a build sheet with all specs and clearances this will help in the future if u keep it and a problem up rises to find out how and y a part has failed these cars see a lot of abuse and get a bad wrap as being Unreliable but these are not average cars most see well over double the stock horse power on stock internals and the ones are always wanting more at some point something is gonna fail. People ask a lot out of these engines least u can do is give it a fighting chance.

 

[bastarddsm]

That damage was probably from cutting the head and not cleaning the oil passages.

 

[911gdsmboostin]

I work at a precision machine shop we only work on extremly expensive race engines mainly v-8 but we see a lot of dohc heads and yes to me it looks like lack of oil but if those caps were mixed up the bores would be off by a few thousands (.001) of an inch and is enough to snuff off oil and leave no room for oil clearence and put pressure on the cam and push into the aluminum bores which will be like a hot knife to butter under heat and pressure (boost) under a load those cams arnt gonna bend u less you used them as a bat for baseball cams are very hard to bend they would break before bending I agree the motor needs a total tear down due to metal in the oil and now most certainly every where you don't want it or just get used motor and replace it and then rebuild damaged motor good luck

 

[bmxfelon420]

Yeah that damage looks like lack of oil and since the caps likely werent on properly, probably due to that. My cams and journals were less damaged when I nearly completely lost oil pressure, so needless to say something horrible has happened to cause this. And the other posters are correct, cams dont bend unless they were damaged while not installed in a car, and if that were the case usually would break from being installed. I've seen that happen before.

 

[oren hughbanks]

It started making noise about 1500 Mile's ago, and I just changed the oil last week and it looked great, not a spec or fleck to be seen .

in the words of forest Gump, that's all I've got to say about that

 

[arrowhead]

You bought a head that was freshly machined, because the head was warped badly, before it was machined, the cams would have been very difficult to turn, did you put the cams on?
The face of the head can be made straight but the head would still be warped.
The damage did not come from the cams or the caps, even mix up caps can not do that much damage I would guess.

 

[oren hughbanks]

I think some of the posts above are probably right, I would say from the coloration of the surrounding area , it was a lack oil, must have had the oiling hole plugged to those cam bearing surfaces.

I definitely learned my lesson here about used parts. I also bought a short block from the same guy, and wasn't planning on using it, just for spare parts. It also ended up being junk mostly, every bearing in it was ruined from contaminated oil[DOUBLEPOST=1416238526][/DOUBLEPOST]I did not install the cams, the caps were on in the right order. Thanks for clarifying guys I appreciate the help.

Still is mighty depressing, took me 8 months and 401k money to complete that build.

 

[briansmith]

Arrow. TOTALLY wrong mixed up caps and totally do that much damage. Cam caps or not symmetrical at all. They a bored out of the head casting be for being cut off and machined for dowel pins. I have seen this before. Cam cap location and orientation is specific to the cam bearing it cam from. Same as the main caps. There is no real magic or science here the head is cast ruff. Mitsubishi was banging them out in record numbers the caps are first line bored then numbet stamped then cut from the head. That is the process with all cast aluminum heads. No two heads are identical this is not a billet aluminum machined head that has be cad cut if u want to check me take two cam caps install it backwards with no cam in place. U will see they don't line up. The pic even shows where the aluminum from the upper migrated to the lower cam bearing all the flaky material is the high spot from the other surface migrating to the low spot on the other. I have seen this numerous times not only from swapping caps. But from missing dowels they are there for alignment

 

[911gdsmboostin]

We all have came from a long way right now my built motor is out and on engine stand with out a car so e times the best thing to do is take a break from it and collect your thoughts and come back prepared it is always a hit no matter how small but anyone who has something good and I mean really good and nice an awesome car and build has had made major sacirfice or have had major setbacks blowouts and so on we all spend a lot of money on this cars sent cheap to build... But we always rebuild the good cars are people that stayed in it after each blow up and ever FCK up. Keep in it !an or you could always go buy a boat something my dad always tells me

You bought a head that was freshly machined, because the head was warped badly, before it was machined, the cams would have been very difficult to turn, did you put the cams on?
The face of the head can be made straight but the head would still be warped.
The damage did not come from the cams or the caps, even mix up caps can not do that much damage I would guess.

Arrow head I promise you mix those capes up see what happens if your soo confident then go flip yours all around.. They do not put index lettering and numbering for their health its very important the their sizes because they are all slightly different camshafts are as important as crank shafts when it comes to caps. As any real car guy and any good machienst they will tell you the same thing

 

[briansmith]

You must be logged in to view this image or video.

This shows a cap installed by eye u can see the cap is not 100% straight on the head that dose not matter from a side shot u would see all the points on the bore diameter are straight in the next cap and the bore itself is perfectly round now if this cap was flipped backwards or ni I improper spot the bore is not round 1 1/2 of the cap would be hanging in and the other out. The in is wore away and pushed into the greatest clearance

 

[oren hughbanks]

Thanks 911gdsm I appreciate the good words, now can u explain that concept to my wife? Haha, yeah I just can't help kicking myself for that cylinder head, I mean I bought it a year ago and it sat for months waiting to be installed I could have checked it over a hundred times!

I'm happy I have another short block on hand. That might be put into service sooner than I thought, and this time ill go with forged pistons, and do 100% of the work myself.

 

[911gdsmboostin]

Take it from someone who knows man and as far as the wife.. ( wify: why do you need to buy all this and spend all this money?? You: because race car that's why..) Enough said if your gonna do it do it right the first time I have all foged internals fresh head don't be afraid to triple check the sizes and demintions theirs a lot you can learn its not rocket science its all about math and having the right number theirs a size you need so make sure you have it. Make sure you oil holes are clean no dirt anywhere and you have hundreds of people to ask how to and what to do. And don't be afraid to ask your local machine shop for advice I can't speak for all but we will usually know and if not point you in a good direction. And research research research just know what you are doing. And if you don't ask don't guess. And before you know it you will make good power blow it up and repeat its the way to a high HP number well if you go to the extream that some do best of luck