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Bent Camshaft

5K views 8 replies 5 participants last post by  AndyFracica 
#1 ·
When I bought the '88 560SEL, the seller and the mechanic both notified me about very slight bend in the cam shaft. They both noted that it is not an urgent matter. There is not even that signature 'ticking' sound which was brought up in several previous posts on cam shaft issue. The mechanic did not exactly tell me when to bring it in but I will know when I hear the difference in engine noise. I have added another 1k since I bought it at at 126k and so far no increase in noise.
I am thinking of taking the car to Boston next week(a 400 mile trip altogether) - should I do it or not?
Also, about how much will it be to fix this known issue?

By the way, timing chain and valve seals were replaced at 113k, along with tranny by the previous owner...
 
#4 ·
Okay, okay, so I flaunted my ignorance here, and I admit that the most I dealt with the issues under the hood are routine fluid maintenance and changing a dead battery.

Perhaps in my mind, I may have interpreted what they said to be 'bent'. In any case, there seems to be a problem with the cam shaft. I feel like I am carrying a time bomb that can go off any time. The best course of action is to fix it before it turns into a major headache, but I was wondering how long I can push it before it becomes a problem.

Also, please let me know what are its signature warning signs...
 
#5 ·
naomilla - 1/17/2004 10:02 PM

Okay, okay, so I flaunted my ignorance here, and I admit that the most I dealt with the issues under the hood are routine fluid maintenance and changing a dead battery.

Perhaps in my mind, I may have interpreted what they said to be 'bent'. In any case, there seems to be a problem with the cam shaft. I feel like I am carrying a time bomb that can go off any time. The best course of action is to fix it before it turns into a major headache, but I was wondering how long I can push it before it becomes a problem.

Also, please let me know what are its signature warning signs...
Typically you don't see a lot of camshaft wear, but typically what you will see is the gradual wearing down of the lobes on the camshaft. What this does is prevent the intake and exhaust valves from opening all the way. If an intake lobe begins to fail, you will get less fuel into the cylinder and will see a power fall-off in that cylinder. If an exhaust valve fails to open you could wind up with burnt valves and again a power fall off.

The long and the short of it is that it will not be a catastrophic failure but a gradual loss of performance.

Change it when you can and you will notice a slight improvement in performance and gas mileage.
 
#7 ·
420SEL Realtor - 1/18/2004 1:25 AM

Andy,

'is it worth replacing both cams with my 168k miles, or is the performance boost too minimal? I imagine running a compression check on all 8 would be a good start?
Actually the compression check won't reveal the condition of the camshaft because the valves will close all the way. They just won't open all the way. [:D]

You could do a dyno test to see what kind of hp the engine is developing. That might tell you how much you have lost.

I would suspect that your compression is most likely fine. I would ask a dealer to take a look at it and make an evaluation for you.

If the dealer pulls the camshaft to look at it you might as well have them replace it because the cost of the part will be minimal compared to the teardown. While its torn down you might as well do valve guide seals and anything else they can get to.
 
#8 ·
PS: Remember if the cams do get replaced, you MUST change the rocker arms also. The rockers are surface hardened and worn into the OLD cam. Even if the rocker surface looks ok,(which they probably won't) they must be renewed or else the new cams will wear prematurely.....
 
#9 ·
BENZDOC - 1/18/2004 1:24 PM

PS: Remember if the cams do get replaced, you MUST change the rocker arms also. The rockers are surface hardened and worn into the OLD cam. Even if the rocker surface looks ok,(which they probably won't) they must be renewed or else the new cams will wear prematurely.....
Yes, good point! [:)]
 
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