Title: Post-War vs Pre-War 170V Parts
Post by: admin on February 03, 2007, 06:56:58 PM
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Title: Post-war vs pre-war parts in pre-war 170 V
Post by: Henry Magno on January 01, 2007, 02:44:54 PM
I found when I was restoring my 38, that I had to make choices about originality of the mechanical aspects of the car. My opinion is that since MB made running improvements to this car through it's long production, it was better, when necessary to update the mechanicals, rather than keep it as built.
Since my car already had a post-war engine, that choice was already partially made. I would have had to look for a pre-war engine. The engine in the car was actually a new replacement factory engine, as far as I could tell, and was supposed to have had only a few hundred miles on it. It was like new when I took it apart. Many of these cars got post-war engine replacements over the years so I'm sure this question comes up often.
I generally think that it's a good idea to use a post-war engine if the car is going to be used regularly and at highway speeds. They have modern thin-wall bearings which should hold up better than the babbitted bearings in the pre-war car. I would do this even if I had the original engine.
Another change I would strongly suggest is changing the front hubs, knuckles, and brakes to the 170 Va version. The spindle is thicker, bearings bigger and the brake shoes go to 40 mm from 30. The pre-war spindles can crack, both of mine were and so were a second set I acquired. That convinced me. If you are using the originals, I would definitely have them tested for cracks.
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Title: Re: Post-war vs pre-war parts in pre-war 170 V
Post by: EThomas on January 01, 2007, 09:03:49 PM
Henry: This is an interesting discussion, so I will throw out my personal opinion, and hope other do as well. (speaking in context of Mercedes 170's) This would vary with the purpose of the restoration, but regardless of if it is a show car, race car, or ?? the basic asthetic sense remains the same to me. While I am no slave to 100% historic content in a restoration, I have developed a philosophy on what to include and what to discard, over half a lifetime of car, boat, firearm and aircraft restorations.
While I am all for hidden mechanical improvements which make a restored car more durable, I am not in favor of "updates." Unless it was available in period, I will not add it. This goes for 6 v electric fans, modern radios, and direction indicators. If the car had a syncros on 2 forward gears, this is how I would choose to present it.
Further, I would rather see a pre-war water pump on a pre war car, as it looks different. I would rather have all my 8mm nuts 14mm across the flats. I seek out original style high tension wires, and spark plugs. The basic goal to me is that no one looking at the car should be able to IDENTIFY any feature which is not correct to the period. This runs to hose clamps, type of hose. Etc.
For example on a race car, I would use a period magnito, but not an electronic ignition module. I would use a larger Solex carb, but not a pair of Weber side drafts.
To me, there is no excuse for "alternator conversions" and other modifications, which are not needed in any case, and degrade the complete old car experience.
Erik
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Title: Re: Post-war vs pre-war parts in pre-war 170 V
Post by: Henry Magno on January 01, 2007, 10:55:43 PM
Well, we probably draw the line in a different place, but I would agree with you on putting modern items on a vintage car. I guess I might say that if something was a normal replacement part within the usual service life of the car, then I would be OK with it. After all, when they redesigned that water pump, my car would have only been ten years old. Cost is occasionally a factor too. If you had to remachine the shaft and housing of that pump, the cost would significantly more than that of a new replacement pump (unless of course you have a machine shop in your basement).
Also, how use use the car has to be a factor. On my last outing with my car, I did about 700 miles in four days, a bit of that at highway speeds, and a lot of hilly driving, with no problems.
I also enjoyed the fully synchronized transmission. If my car didn't already have it, I would have changed it. Since the factory introduced that transmission in 1938, why would I be inconvenienced with the older transmission if I happened to be restoring a 36 or 37?
I put a number of miles on a 37 230 with the Maybach transmission and I can say that it really detracts from the pleasure of using the car. Shortly after, they starting using the fully synchronized ZF unit. The owner of the 230 would like to change it to the later unit, if it can be done. I don't think this is "modernizing" an old car since it was done when the cars were still in production.
