74 impact bumper strut...

Discuss with fans and owners of the most luxurious aircooled sedan/wagon that VW ever made, the VW 411/412. Official forum of Tom's Type 4 Corner.
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vwfye
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74 impact bumper strut...

Post by vwfye »

my driver's side bumper strut is sprung... can these be reset or is it toast?
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raygreenwood
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Post by raygreenwood »

I believe there was a thread for this somewhere. I think you drill a small hole and relieve the internal pressure and mechanism. It will never operate again...but can be brought back to normal position. Ray
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vwfye
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Post by vwfye »

ah... i was gonna do that and use a bolt to keep the 2 halves in place. are these oil filled or gas filled?
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wildthings
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Post by wildthings »

If you ever get up Portland way the is a good set of bumper struts on a 74 412 at Parts Obsolete in McMinnville. Ask for Gary.
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vwfye
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Post by vwfye »

don't tell anyone, but i want to tuck the bumper in closer to the body...
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raygreenwood
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Post by raygreenwood »

They were oil filled I beleive. Ray
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vwfye
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Post by vwfye »

thanks ray! i know this isn't stock, but i'm trying to only make functional changes. btw, the suprise from the nose being lowered? 2 mpg increase in fuel efficiency.
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raygreenwood
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Post by raygreenwood »

Yes. That is a benefit as well. Its amazing how even setting the front end dead level....even without serious lowering....realy tames the wind action on the front end.
Not to mention how lowering the front end to level or lower....gives greater static castor angle. Bump steering and cross wind wander improve across the board.

I had noticed the gas milage increase as well...but was doing so many other improvements at the same time....that it was a while before I could put my finger on the front end being lowered...as a milage improvement. Glad to see another car helping to verify that.

These are really nice handling cars when set up properly. Ray
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vwfye
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Post by vwfye »

drill and drained the blown bumper strut... i still cna't get it to budge! augh!!!!
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vwfye
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Post by vwfye »

man, i still can't get the strut to relax back into place. i took the 3lb sledge to the strut and couldn't get it to move... i'm sure it is a rust issue, just can't seem to win this one. grrr
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raygreenwood
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Post by raygreenwood »

This is sparking a very dim memory....but....I think...there may be a "one way" shaft/rod clutch inside. I thought there might have been on some other bumper impact struts...precisely to keep people from doing what "we" would do.....getting them re-extended and driving on. :lol: Try a search for bumper struts. I think someone had this problem before. Ray
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raygreenwood
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Post by raygreenwood »

Ah! found it. The original thread was on Thursday May 12th 2005. Kirk knighton was the poster. I think Albert or MGVW fan noted that some shops will install a "zert" in the back of the shock and pump it full of grease to expand it. But....I would worry that it would then make the shock so stiff that another hit may cause real damage. But.....you can fill most grease guns with say...tranny fluid or oil....and then pump that in. Most grease guns make several thousand pounds pressure. Then relase the excess pressure on teh "zert". Give it a try! Ray
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vwfye
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Post by vwfye »

hey ray,
i looked at that thread... it talks about re=extending the strut. mine is the opposite! mine is not compressed in farther than stock, mine is extended out farther than stock. almost 4 inches farther! i drilled the set out and drained the oil but it still will not recompress. maybe i missed something in the thread. wouldn't be the 1st time.
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raygreenwood
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Post by raygreenwood »

Actually....it was ME that missed that yours was over-extended in this thread :shock: . I'll have to think on this one. It must have a catch inside or something. Its one of the few parts I have not cut open to investigate. Perhaps a superbeetle one is similar? Ray
albert
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74 impact bumper

Post by albert »

hi, ray ,, for this impact bumper ,, the systhem is that, you push the bumper ( very hard to pus-in ) and he have one steell hoock from the bumper frame to the shock frame , ( factory instalation ) for to keepe the schock in place , wend you got small accident , the hook go down and the shock bumper go outside of the frame for appx.4" i thing i have the picture with the shock in the normal position ( before accident ) on 412 with the exact position for the hoock,this hoock is under the shock and hit is 4" appx. long ,albert
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