Bilstein shock in Boge strut... tight fit ???

wildcat077 · wildcat077's Garage

Just wondering if anyone ever had this problem ?
I replaced my original Boge shocks in the Boge struts with Bilstein HD's and one side went well but on the other strut my shock doesn't go all the way in,it still needs to go in another 4 inches and it seems to bind somewhere down at the bottom...
I don't want to force it in otherwise i will never be able to remove it again !
Any ideas ???

wildcat077 · wildcat077's Garage

Anybody ? I'm kind of stumped here...
If there's no sensible solution,i'll bring the strut to the machine shop boys at work tomorrow and have them bore out the inside of the strut until i get enough clearance to slide the shock body all the way down !

I was curious if anybody else had this issue ???
Thanks !

cgarr · cgarr's Garage

I did the same and all went perfect, is the strut dented or bent maybe?

tobluforu · tobluforu's Garage

Sounds like the strut is bent and this may mean you need a new one. Can you take the new insert out of the other side to see if it will fit in the problem side?? If not, then strut is tweaked I would think, or is there something in there or stuck to the inside? Not sure it's a great idea to bore the strut out?

CBRacerX · CBRacerX's Garage

I had the same issue. Strut is bent. Replace.

wildcat077 · wildcat077's Garage

It seems to bind where the weld is at the large yellow dot ...
Can't see it being bent as that is a pretty solid part of the strut assembly.
The Boge shock insert is a much smaller diameter so there was no clearance issues before.
The previous owner never mentioned having any problems getting the car aligned,although i'm not sure the local Porsche dealer would know the difference as they only specialize in newer cars.

I'm going to bore out the inside of the strut tomorrow and i will have the car aligned by a specialist Porsche guy who's been doing them for over 40 years.
I would imagine he would be able to pinpoint any damaged strut issues !

I will keep you posted on the results !

Thanks guys !

CBRacerX · CBRacerX's Garage

The bend is not at the weld, but above it. Since the shock is "aligned' by the upper part of the tube, it ends up going into the lower area at an angle. If you can bore it out and align it, great. Bent strut is not terrible per se if you can get the alignment specs you want and bump steer is not impacted.

wildcat077 · wildcat077's Garage

I rigged up a tool to clean out the inside of the bore but it is not enough,gained maybe .250 only,that is after going away with my high speed grinder for almost an hour !

It definitely is tighter at the spot where the steering arm was welded to the strut,that is where the large yellow dot is... as my abrasive wheel is the same diameter on top as the upper part of the strut !

siverson · siverson's Garage

It's bent x3.

jevvy · 06-24-2009, 11:31 PM

It might not be the strut thats bent but instead the spindle has bent up(due to hitting a big hole or kerb) and caused a high spot in the tube.

I battled to get my insert fitted with similar problems only to regret it once I went for alignment and they couldnt get the same camber at the front on either side.

tvanbroekhoven · 06-24-2009, 11:38 PM

It's maybe me, but even looks bent.

so x4

tobluforu · tobluforu's Garage

Quote:

Originally Posted by tvanbroekhoven

It's maybe me, but even looks bent.

so x4

I thought the same thing, but pics can be deceiving.

kucharskimb · 06-25-2009, 09:54 AM

Hey,
while you have that out, can you give me the INSERT dimensions. I just need the green body OD and the body length.

Thank you.

rnln · 06-25-2009, 10:03 AM

or maybe it is rewelded and that made the ID shrink at that point only?

jurhip · 06-25-2009, 11:33 AM

If you have access to a machine shop, you can just as easily check it for runout. If its bent, you could try removing material, but the area around the spindle is a high stress point. Personally, I would check it for straight. If bent, get a new one.

You can also try ot take a thin straight edge and see if there is a high spot in the ID.

wildcat077 · wildcat077's Garage

O.K. guys,here's the lowdown for those of you who were thinking as using your "presumably"
bent struts as boat anchors... lol

Turns out the bore at the weld point on the strut had a smaller I.D. than the remaining part of the strut with the narrow I.D. (that would be 4.750 from the bottom where it steps down)

Could have been due to the penetration from the weld or material warpage also due to the welding process.
This was measured with a bore gauge which led to cleaning out the inside bore with a 1.750 cutter.
Now here are some measurements for Matt...

The total length of the insert is 24.250 and the body of the insert is 1.815 at the thickest point whereas it measures 1.725 at the narrowest point which is 4.750 inches from the bottom where it steps up.
Now the inside diameter of the strut is 1.925 which gives approx .100 clearance all around for the Bilstein shock as compared to the thickest dimension of the original Boge insert which measures 1.370 in diameter.
As you can probably see the tolerance was much larger for the Boge inserts which were installed some 20 years ago.
It's possible that some passed through inspection with a + or - let's say .063 mismatch which would still be okay for the original Boge insert...

I also spoke to the PO which is a friend of mine and he had the car aligned twice while he owned it and had no issues with proper alignments !

So the bottom line is,don't junk your struts because you have a hard time fitting an aftermarket insert,it's way cheaper to go to a machine shop and have the inside bored out to restore the proper I.D.
In my case i'm a tech at a major airline so i had access to all this,but any machine shop could do this for you in less than 30 minutes... Takes longer to set up than to do the job !

Time to go play in the garage again

wildcat077 · wildcat077's Garage

Oops... Sorry Matt !
The green body length measures 14.5 inches !!!