Printable Version of Topic

Posted by: framos914 May 14 2019, 09:31 PM

Need help. My 75 2.0 has worn strut inserts, PO replaced front struts with what I believed were 1977 911S Koni struts part #911 341 079 16 stamped on it. Bought inserts Koni 86-1942. Problem is they bottom out before going in far enough to secure them with the round nut.
Could I have 72-74 911S struts? Did they have the same part number? And are those inserts (86-1638) just a little shorter to seat further down. The 1942s seem to be just about 12mm too long, body of the 1942 is 374mm long.

Tried getting info from a few places including Koni but no luck.
Thanks

Posted by: mepstein May 14 2019, 09:47 PM

Off the top of my head, it sounds like you are trying to put inserts made for 3 1/2" struts into a 3" strut. The later strut bodies are taller than the earlier ones.

Posted by: framos914 May 14 2019, 09:58 PM

The struts are 3.5 inch, It also has the 911S aluminum calipers not the M calipers which I believe are the 3 inch.Even though the the receipt in the POs documents say 1977 suspension, it could be wrong. These components were installed on this car way back in 1980.

Posted by: infraredcalvin May 14 2019, 10:01 PM

it appears you have even earlier struts for 914-6/ 911 and 912, 68-72?

There is a superseded part number you get when searching which may be what’s fouling up your search.

Posted by: Larmo63 May 14 2019, 10:04 PM

Pictures might help us here, too.......?

Posted by: framos914 May 14 2019, 10:13 PM

I'll try to get pictures tomorrow if the mechanic at the shop doesn't sort it out. Getting the 86-1638 Konis tomorrow but cant find those dimensions to see if the're a bit shorter.

Posted by: porschetub May 14 2019, 11:47 PM

I ordered replacements for what I knew were MY for my alloy crossbar,turned out I was right as the struts are the same era (911 SC) honestly had no idea.
Took a gamble really cause the OP also told me my gearbox was ok .
Part numbers change but those better than me have spoken,I will say I have been bitten before on wrong numbers.

Posted by: 914Sixer May 15 2019, 06:02 AM

I have a set of Koni 86-1942 and I have test fitted them in stock 73-on Boge Struts. You have to use the Boge nut but they fit. I have a set of 86-1647 which are made different but fit the same.

One on right is the 1942 and left one is 1647. BOTH are the same length. 14 1/2 inces or 37 cm.


Attached image(s)

Posted by: sixnotfour May 15 2019, 08:56 AM

real Koni Struts.. require a unique shock insert ...call paragon products Koni 86-1638

https://www.paragon-products.com/Koni-Strut-Insert-86-1638-p/86-1638.htm

Posted by: framos914 May 15 2019, 03:38 PM

Thanks
Spoke with Jason at Paragon, he is 100% sure there is something at the bottom of the strut keeping the insert from dropping all the way down. The mechanic disagrees so I'll follow Jason's advice, pick up the car and take it apart myself.

Posted by: mepstein May 15 2019, 03:57 PM

If it’s just one strut insert that won’t go down then I’m betting on a bent strut. If it’s both sides then I got nothing.

Posted by: sixnotfour May 15 2019, 09:38 PM

real Koni Strut housing /Spindles are special

Posted by: framos914 May 16 2019, 12:02 AM

Passenger side strut

Posted by: framos914 May 16 2019, 12:03 AM

Posted by: framos914 May 16 2019, 12:05 AM

Old insert

Posted by: framos914 May 16 2019, 12:11 AM

New 861942 insert

Posted by: 914Sixer May 16 2019, 06:12 AM

I have never seen that type of Koni insert. The numbers I am seeing says it is 75-up strut. Made week 34 1974. Wondering about spacer in bottom of tube.?

Posted by: infraredcalvin May 16 2019, 07:50 AM

Something has to account for that tab at the bottom of the original insert.

Posted by: framos914 May 16 2019, 10:23 AM

The tab has two sides, I think on the original the shaft gets pushed down manually and catches on something to make ride adjustments. Next I'll take the strut completely out to have a good look in the housing and make there's nothing inside the housing

Posted by: sixnotfour May 16 2019, 01:09 PM

your missing some pieces,,ie still in tube..


Attached image(s)

Posted by: framos914 May 16 2019, 02:49 PM

Thanks for that picture, might be that round piece at left is still in the tube. Any Ideas on how to get it out? Hope to avoid removing the whole strut assy.

Posted by: sixnotfour May 16 2019, 03:18 PM

magnet and thump strut with plastic hammer

Posted by: framos914 May 16 2019, 09:57 PM

Thanks again, that was it! Got those inserts in. Used a magnet and brought it right out. The mechanic should have tried the magnet.
Last question, intructions show 50ml of oil in housing. What is the best oil to use? Picure on instructions shows what looks looks like a snowflake.

Posted by: sixnotfour May 16 2019, 10:17 PM

Question: Some friends told me I ought to put some type of coolant in my strut housing before I install the insert. What are they talking about?

Answer: It's a good idea, particularly if the car is tracked, to put a the strut tube prior to installing the insert. You can use a 50/50 mix of water and antifreeze or hydraulic oil. Many inserts that you remove prior to installing your Koni's, will leave hydraulic oil in the tube. You can use this oil or the antifreeze mix. You'll want the coolant level to be about 2/3 of the way up the insert. It won't take much fluid because the insert will displace most of it. Use the dipstick method to check the level of the fluid. A paper towel can be used to soak up excess if needed. Never run straight water in the tube as if may freeze and collapse your insert.

Posted by: sixnotfour May 17 2019, 01:36 AM

Question: What a rip, my 911 has original Koni struts and many places are telling me the only thing I can install are hydraulic, standard adjustable Koni inserts. Seems strange that I have the wiz bang original Koni strut and I can't even use Koni's externally adjustable gas insert.

Answer: This used to be true. We were able to modify the gas insert to fit original Koni struts (at extra cost) but recently Koni made everyone's life much easier. A change in the design of the insert will now allow you to utilize the externally adjustable gas insert in your original Koni strut. You do have to use the correct production date insert though.