worn cam lobes...

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I recently had a lifter and rocker arm replaced and the mechanic said my cam lobe is worn past the hardened coating down to the softer metal and my time is limited on that camshaft. I want to know what metals would show up excessively in a UOA if the cam was wearing like he said. -Nick
 
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Iron. What type of car. Mileage. Driving. Are we talking about? I would also get a second opinion as a LOT of mechanics should be working fast food and not working on cars.
 
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 Originally Posted By: SuperDave456
I would also get a second opinion as a LOT of mechanics should be working fast food and not working on cars.
That's the truth! Recently there was a "VW line mechanic" on one of the forums throwing out some of the craziest stuff and doing it like he is some kind of expert on the subject. Makes you discouraged because all of the people who know better have to correct the guy on every post and nobody has that much patience I think. ...Also see my sig line.
 

EcoB00ST

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It's a 2000 Chrysler 300m. Well maintained. 70% 30% City Highway I agree. I don't believe him. That is why I am going to have a UOA done and see what kind of metals are showing up. If it is the way he described, something will be excessive, I just want to know which metals to look for to prove or disprove his claim...
 
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beaver land EH?
Whenever in doubt, always seek a second opinion from another trustworthy mechanic. Wear or not, your best bet is to get someone to pull the valve cover again and do a micrometer check on the lobe in-question and against factory spec/other lobes. If it's worn, service it. If not, pack everything back and drive happy. I wouldn't spend the time/effort on UOAs for I hate waiting. Q.
 

PT1

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 Originally Posted By: 300m2000
I recently had a lifter and rocker arm replaced and the mechanic said my cam lobe is worn past the hardened coating down to the softer metal and my time is limited on that camshaft. I want to know what metals would show up excessively in a UOA if the cam was wearing like he said. -Nick
I am surprised that he didn't call you and show you the worm cam lobe. My mechanic would have called me and asked if I could come to the shop to see for myself. At that point it would have been my decision to buy a new cam while it was apart. It is possible you got a soft cam from the factory but for him to just mention it is unusual. Usually they want to repair a root cause like that.
 
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Since that's an over head cam engine the cam should have been replaced while the other work was done. Still a lot of value left in that car.
 

EcoB00ST

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It was the dealer, they never offered nor could I get free from work that day to check it out. It would have been ideal. At this point I'm hoping to catch this alleged excessive wear in a UOA. Something would show up abnormal if his claim were true. Does anyone know which metals I should look for to catch excessive cam lobe wear?????
 

EcoB00ST

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 Originally Posted By: RWEST
What engine is it?
It's the 3.5 V6 only engine of that yr. This is the older 300m that ran from 99-04.
 
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even if you are able to provide excessive Fe in your UOA reading, w/o any actual evidence (e.g. pull your cover off and take the actual measurement against factory spec or other healthy lobes, your proof would be vague and meaningless at best. In that case, dealership/mechanic can simply discount your evidence (I would too if you present me UOA on a cam lobe situation w/o providing me the actual reading). Why are you so obsessed with UOA? Q.
 
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How many miles on that engine? Could the defective lifter and rocker arm have caused the extreme wear to that cam? Did he say that more than one cam showed excessive wear?...or just that one under the bad parts? I agree with the others; arrange for a time when the camshaft can be exposed, take a good look with another mechanic, and try for photos you can post here, especially if anything about that cam looks different from the other cams on the camshaft.
 
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You never replace just a lifter without replacing the cam. Don't get your hopes up on the UOA. I had an engine self-destructing and it only showed slightly higher levels on a UOA. When I pulled it apart, it looked like it had a million miles on it.
 
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300m2000: That tech did you a real disservice. Once a camshaft is worn through the hardening, it goes flat very quickly from there. It will toss lots of metal into the oil and, in theory, that could cause other wear issues. If the lobe was bad, he should have estimated the replacement then and given you the option of a full and complete repair before putting the engine back together. This way, he gets to bill you twice for a lot of the same work. Might be time for a new technician and/or a second opinion. A UOA may be able to pick that up but IMO an inspection, both visual and measuring the lift on that lobe, then comparing it to the service specification, is what's really needed. Unfortunately, that will entail some level of disassembly.... again and some labor. Hence my comment on the level of disservice. You get the regrettable privilege of paying twice for the same work.
 
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A UOA may not pick anything up actually if the particles are too large.
 
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Agreed with Jim. We had a project in the turbobuick community called the "budget roller cam". It was just that, cheap. We had about 40 of them go flat and with very rare exception, it took the entire engine with it. The only one I'm aware of that didn't fail had a huge filter with no bypass and an inline filter on the turbo feed. At a minimum it's probably time to change the oil to keep the metal out of the engine.
 

EcoB00ST

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 Originally Posted By: Jim Allen
300m2000: That tech did you a real disservice. Once a camshaft is worn through the hardening, it goes flat very quickly from there. It will toss lots of metal into the oil and, in theory, that could cause other wear issues. If the lobe was bad, he should have estimated the replacement then and given you the option of a full and complete repair before putting the engine back together. This way, he gets to bill you twice for a lot of the same work. Might be time for a new technician and/or a second opinion. A UOA may be able to pick that up but IMO an inspection, both visual and measuring the lift on that lobe, then comparing it to the service specification, is what's really needed. Unfortunately, that will entail some level of disassembly.... again and some labor. Hence my comment on the level of disservice. You get the regrettable privilege of paying twice for the same work.
He did recommend replacing the camshaft. I was just not in the financial position to drop $2400 on a car thats worth $3000. It was a tough decision but the price was a bit of a rip off considering they had the engine open already and could have easily slapped on a new camshaft for less than what they quoted me for. Hence why I didn't fully trust their recommendation. I figured if the metal is gonna wear the way they say it is then something will have to show up in a UOA. I understand there's a chance it won't, but its all I can do at this point in time. I may pull the valve cover myself, its just such a pain in the @$$ to remove the plenum above. If I do crack it open I will definitely post pics.
 
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Replacing one camshaft should have been few hundred dollars max. It causes some doubt that the mech was telling the truth about the cam wear.
 

EcoB00ST

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 Originally Posted By: Quest
even if you are able to provide excessive Fe in your UOA reading, w/o any actual evidence (e.g. pull your cover off and take the actual measurement against factory spec or other healthy lobes, your proof would be vague and meaningless at best. In that case, dealership/mechanic can simply discount your evidence (I would too if you present me UOA on a cam lobe situation w/o providing me the actual reading). Why are you so obsessed with UOA? Q.
Not so much an obsession than being the most feasible method considering my situation. I don't have the time in the near future to pull the plenum or valve covers myself. Nor is it financially possible to get raped again like I did by the dealer. The possibility of detecting excess wear, like the mechanic claimed is occuring (due to the lobe being worn down to the softer metal), is the most practical method in my situation.
 
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$2400? Impossible with just a cam replace. Listen to Quest, others when they say pull the valve cover then you'll have your answer with 100% accuracy. Running UOA tests is similar to reading tea leaves in that situation.
 
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