whitedog
Veteran Member
Quick question: Does anyone know FOR SURE that the stock PD cams are just surface hardened, or are they hardened deeper?
Good questions, but irrelevant to the reason for my post. I'm afraid that this will sidetrack the purpose of this thread.VFchicago88 said:What about PD cams failing with exclusive 505.01 usage? What about Gmark who has ran a PD cam on delvac for what, like 90k and the cam still looks new?
Dont cams and lifters fail in ALH motors too?
too much pressure is the main cause, in addition to other issues caused by high engine loads, lube failure, hardening issues, etc.Powder Hound said:Isn't the problem also in the lifters? It seems to me that both parts are involved in the problem and solution.
90k is not much on a PD, although i have seen cam failures earlier than that.VFchicago88 said:What about PD cams failing with exclusive 505.01 usage? What about Gmark who has ran a PD cam on delvac for what, like 90k and the cam still looks new?
Dont cams and lifters fail in ALH motors too?
I have no idea.whitedog said:Quick question: Does anyone know FOR SURE that the stock PD cams are just surface hardened, or are they hardened deeper?
How many of those cars ran Mobil 1 5w30 aka "What oil do you use?", "I only use synthetic oil in my TDI".jasonTDI said:LOTS of 02' model year cam/lifter failures. I've done 40 sets in 2 1/2 years. Plenty of the other years too around the 200-225K mark.
Joey, I visited your website and there is NOTHING there about TDIs! What's up with that?FC735 said:the three we have pulled lately appear to be surface hardened only, due to the rapid deterioration with incorrect oil being used.
i have one in right now that i am writing a case study for a trade magazine on showing the effects of a non 505.01 oil in a PD. customer swore by Amsoil to start with, now swears at it.
i will cut this one later tonight to verify, but i am positive that they are simply surface hardened.whitedog said:WAY off topic and I'm hoping to stay ON topic here folks.
All I want to hear about is facts regarding the depth of the hadrening on the PD cams.
Oils, folllowers, driving styles, the latest exploits of Paris Hilton... Please leave them elsewhere. If I'm asked to stay on topic, I do, and I hope that others will do the same.
So, the original question is are the PD cams surface hardened, or are they hardened deeper?
That would be great. If you could let me know, I'd appreciate it.FC735 said:i will cut this one later tonight to verify, but i am positive that they are simply surface hardened.
it would be very costly and downright impractical to have a fully hardened cam shaft. the engine vibrations would shatter it in a heartbeat.
Thanks Frank. What are your thoughts on polishing the cam?Franko6 said:If you look at the ends of the cams, you can see exactly how deep they are hardened. On the dwell portion, they are not flame-treated very deeply. On the lobe surfaces, the hardening goes through to a circle nearly the depth of the dwell portion of the camshaft.
That's on topic...
As for the lifters, they are heat treated after grinding. I think they have nitrided the surface for additional wear characteristic.
I am currently experimenting with some PD lifters to see what I can find out. VW's $30 per lifter is a bit hard to swallow...