Background (for those of you who don't know me)
I was driving the car normally and turned off the AC. That is when I heard a loud(ish) rattlethat sounds like it’s coming from the upper end of the engine . Seemed to start suddenly after AC was turnedoff, but it might just have been masked. I am new to Greenville, so I looked around for people who could work on it. The local Acura dealer has an NSX tech, but he is out on medical leave. The owner of a local well-known independent shop says he was an NSX tech at a California dealership for many years before coming to Greenville, so I had the car towed to him (it ran fine, but I didn't want to do any damage). I researched the issue here, and let him know that it might be lost motion assemblies, coil packs, or a failing timing belt tensioner. Frankly, I was a little insulted at first at his response: I'm a typical NSX owner who thinks he knows what is going on with his car but doesn't. However, it didn't insult me too much because he is right that I am far from a mechanical expert.
Last week, after having the car for a week and working on it in his spare time (he owns the business, so he can only work on it when he has the chance), he called me and said "dude, you might need a new engine". He said he felt far more crankshaft endplay than Honda's are supposed to have. I pressed him a bit, and he measured it again and said that the endplay was actually within spec, but toward the end of the spec. He said it was looser than he was used to seeing. I was a bit worried by this and dropped by on Friday with the intent of telling him "thanks" and looking for someplace else to take the car. However, they had started taking it apart and are going to run it with the valve covers off to see if the crankshaft is "walking" when the engine is going. To be clear, I had given them permission to keep going when they called initially. But I was concerned by his initial assessment.
The Ask
I would appreciate advice on this matter. They are basically tearing down the engine to see if they can find the source of the sound. Is there anything I should point them to? The car has been impeccably maintained throughout its life and is very tight and solid.
Good News for Other NSX Owners
When I dropped in on Friday, I took some pics of the engine internals and valve cover. I could not believe how clean the engine was after having run 126k miles. Honestly, it looked like it had just been assembled. Here are some pics:
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- I have a 1995 NSX with 126k miles and two owners. The first owner had it until 2014; I have had it since then.
- Only two mechanics have ever worked on the engine. The first was Carl Dehls, a legendary NSX master tech at David McDavid in Plano, TX. He dideverything from timing belt services (2) to windshield wiper changes. I had it serviced at Source1 in Cincinnati
- The last "majorservice" took place at 118k miles in Oct 2012. Timing belt / water pump / drive belts were replaced, the valves were adjusted with new gaskets, the cam caps were replaced, leaking vtec spool valve o-rings were replaced, a leaking oil pan gasket was replaced, and the spark plugs were replaced.
I was driving the car normally and turned off the AC. That is when I heard a loud(ish) rattlethat sounds like it’s coming from the upper end of the engine . Seemed to start suddenly after AC was turnedoff, but it might just have been masked. I am new to Greenville, so I looked around for people who could work on it. The local Acura dealer has an NSX tech, but he is out on medical leave. The owner of a local well-known independent shop says he was an NSX tech at a California dealership for many years before coming to Greenville, so I had the car towed to him (it ran fine, but I didn't want to do any damage). I researched the issue here, and let him know that it might be lost motion assemblies, coil packs, or a failing timing belt tensioner. Frankly, I was a little insulted at first at his response: I'm a typical NSX owner who thinks he knows what is going on with his car but doesn't. However, it didn't insult me too much because he is right that I am far from a mechanical expert.
Last week, after having the car for a week and working on it in his spare time (he owns the business, so he can only work on it when he has the chance), he called me and said "dude, you might need a new engine". He said he felt far more crankshaft endplay than Honda's are supposed to have. I pressed him a bit, and he measured it again and said that the endplay was actually within spec, but toward the end of the spec. He said it was looser than he was used to seeing. I was a bit worried by this and dropped by on Friday with the intent of telling him "thanks" and looking for someplace else to take the car. However, they had started taking it apart and are going to run it with the valve covers off to see if the crankshaft is "walking" when the engine is going. To be clear, I had given them permission to keep going when they called initially. But I was concerned by his initial assessment.
The Ask
I would appreciate advice on this matter. They are basically tearing down the engine to see if they can find the source of the sound. Is there anything I should point them to? The car has been impeccably maintained throughout its life and is very tight and solid.
Good News for Other NSX Owners
When I dropped in on Friday, I took some pics of the engine internals and valve cover. I could not believe how clean the engine was after having run 126k miles. Honestly, it looked like it had just been assembled. Here are some pics:
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