Pressing shock absorber bushes

Pressing shock absorber bushes

Author
Discussion

Dalamar

Original Poster:

251 posts

75 months

Friday 23rd October 2020
quotequote all
My car needs the shock absorber bushes on the fronts changing and it has the larger 42mm (C0414) bushes at the top and standard 27mm wide ones at the bottom (C0092).

Has anyone tried pressing them out (and also installing them) using a ball joint press? Something like this:

https://www.amazon.co.uk/Heavy-Duty-Joint-Press-Re...

Basically a large, strong C-clamp with a selection of receptacle cups. Obviously, you'd need some suitable sockets to press with too.

I was wondering if the C-clamp and a big breaker bar or an impact driver would be up to the job of pressing out the larger 42mm diameter top bush. I'm sure it could handle the smaller one.

I contacted Ben at Blackdown Auto and he said that a 5 ton press would be needed as a minimum. He uses a 10 ton press for his word. I contacted my local independent garage that MOTs my TVR but they don't have a press (just a big vice).

What are your thoughts please?

sapper

1,133 posts

205 months

Friday 23rd October 2020
quotequote all
Whenever I’ve done it I drilled lots of holes in the rubber them melted the centre out with a blow torch. The outer bush sometime came out with a chisel but more often than not I cut a line with a hack saw and they tap out quite easily.
First time I replaced the bushes with power flex which went in easily. Second time I used original type bushes and pushed them in with a socket and a vice.

RobXjcoupe

3,172 posts

91 months

Friday 23rd October 2020
quotequote all
As above. With metal sleeve bushes heat the sleeve to melt the glue holding the rubber in. It will simply tap out. Then carefully cut just the outer sleeve with a hacksaw. Then that will tap out. Thoroughly clean the inner diameter of the damper and lightly grease ready to push new bush in via the bush outer metal shell. Don’t just push against the rubber centre. A hydraulic press is best but a vice can be used just push via the bush outer metal shell wink

Paulprior

864 posts

105 months

Friday 23rd October 2020
quotequote all
I would spend an extra £40 and get a 12t press, but even then I would recomend standing the arms on their side and leave overnight with a good dosing of penetrating oil, I then turned them 180 and let the oil soak in from the other side, I actually used a 100t press and saw the gauge going up to 15 to 20t when dry, but after soaking in oil as described it only used about 5t

Dalamar

Original Poster:

251 posts

75 months

Saturday 24th October 2020
quotequote all
Thanks everyone. For penetrating oil, do you think standing the ends in diesel overnight would be good?

sapper

1,133 posts

205 months

Saturday 24th October 2020
quotequote all
Dalamar said:
Thanks everyone. For penetrating oil, do you think standing the ends in diesel overnight would be good?
Can’t see it doing any harm,


over_the_hill

3,188 posts

246 months

Saturday 24th October 2020
quotequote all
Is there a local garage that might be able to do this for a few quid. Especially if the shocks are already off the car so it's a quick pop-out and press-in. They will probably have a bench press and save you much huffing and puffing.

RobXjcoupe

3,172 posts

91 months

Saturday 24th October 2020
quotequote all
How old are the dampers? If the bush outer shell is rusty they won’t push out, no matter how much oil you soak them in. If the dampers are just a couple of years old you may get away with a bit of oil once they move. You need to remember they are an interference fit so no gap for oil to run between.

Steve_D

13,747 posts

258 months

Sunday 25th October 2020
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Re the dampers steel or ali bodied?
If ali then the bushes will be corroded in and will most likely split the housing if you try and press them.
Better to cut the bushes out and perhaps use poly bushes as replacements.
If cutting them out then rather than drilling or burning the rubber us a hole saw. Much quicker and less smell.

Steve

Dalamar

Original Poster:

251 posts

75 months

Monday 26th October 2020
quotequote all
Steve_D said:
Re the dampers steel or ali bodied?
If ali then the bushes will be corroded in and will most likely split the housing if you try and press them.
Better to cut the bushes out and perhaps use poly bushes as replacements.
If cutting them out then rather than drilling or burning the rubber us a hole saw. Much quicker and less smell.

Steve
My shocks are the standard Bilsteins with the large top bush and smaller lower bush. Can't use polybushes for the tops as they aren't available as far as I know.




Dalamar

Original Poster:

251 posts

75 months

Tuesday 10th November 2020
quotequote all
Well - I decided to buy the cheapest ball joint press on eBay and guess what - it worked! Using penetrating oil helped too.

I had some old rear shocks to try this out on with the 27mm C0092 bushes fitted. Firstly, the top bush. I used suitable sockets and a 60cm breaker bar for leverage. I could have used an impact gun but I preferred to do this carefully in case something went pop.

Here is an example pic of my setup.



Note the thread is well oiled and the head of the press is greased. Give it some ummph and you hear a crack as it starts to move. Mine were quite old and corroded as you can see. Adding more penetrating oil after the first movement really helped and it was simple to continue to press them out.

The hole at the end of the press was a suitable size to run out the bush as my large socket (32mm) wasn't quite deep enough.



Easy peasy. Now to try the bottom ones. These were more corroded and initially wouldn't budge. I ran out of ummph before the press did as I was just levering against the shock on the floor with the breaker bar. Anyway, I knew I needed a different approach so I ran a hacksaw through the centre with the centre metal sleeve still in and made a cut through the metal sleeve, through the rubber material and almost to the edge of the bush without breaking through. This was easy to do in the vice.

Now I setup the press again, a little penetrating oil and this time it moved just like the top one.





As you can see, this bush had been damaged in some way by a previous installer and this had added to my struggle. The pics hopefully show that I didn't cut all the way through the bush and score the shock eye.

This method works by releasing some of the strain of the bush in the shock absorber eye and allowing the cut to collapse a bit as the bush starts to move under load.

So for more practice I repeated my method on my other old rear shock and pushed out the bushes in the same manner, a relief cut being required for the more corroded bottom bush. I did those two bushes in less than 30 mins all by hand with no cold chisels or damage to the shock eyes at all. I could see when I'd pushed out the bushes where previous owners had nicked the eyes in the past.

Here is a pic of the second bottom bush that I had relief cut.



This gives me confidence now to tackle the fronts on my car now and the bigger top 42mm C0414 bushes should push out using the same method. Total cost was £25 for the press.

Hope this helps people.