24 replies to this topic

[mx5nut]

I am moving into changing out my cones and shocks and ran into an issue with the knuckle joint seeming to be stuck in the trumpet. I have the spring compressed properly and everything taken care of with the top arm bolts removed and the rebound buffer removed so the top arm rotates down as far as possible.

The knuckle joint seems to be stuck up in the trumpet. I don’t know if it is possible for trumpets to rust or get stuck to the cones as well, but everything seems to be seized together and I’m not sure what to do now. If I could get the knuckle joint to slide down out of the trumpet, I think I would be able to move forward with getting the bottom arm out and then on with the trumpet and cone.

Anyone have insights on how to get the knuckle joint free from the trumpet and then separate the trumpet from the cone?

[Tornado99]

What about heating with propane the joint to soften/melt the plastic piece?

[timmy850]

Mine was completely fused together too

Can you completely remove the top arm?

If you are putting in hilos another alternative is to cut the trumpet in half

[RooBoonix]

Do you mean the metal ball end of the knuckle joint? If so, you wont get that to slide out of the trumpet on the car, you need to remove the trumpet with the knuckle ball still in it and hammer out the ball on the bench, heat helps here, if you are changing the joint.

 

If the trumpet is stuck to the cone then as mentioned above, remove the top arm complete with trumpet and cone and separate on the bench.

 

It sounds like you can rotate the top arm down though from your post, implying the trumpet is free from the cone? So you should be able to remove the trumpet with knuckle ball attached by prising the trumpet upwards and it should pop out of the plastic seat, it can be a bit tight in the subframe tower and sometimes removing the top arm does make life much easier, you can check out the top arm bearings and remove old dirty grease from there whilst you're at it too.

[mab01uk]

About 8 minutes in:-

 

 

 

 

About 9 minutes in:-

 

 

Edited by mab01uk, 08 July 2021 - 09:23 AM.

[mx5nut]

Attached is a photo of what I am looking at. Do I need to get my BFH out and whack in the trumpet a bit to break it loose from the cone? I can’t quite get the upper arm out from under the ball of the knuckle joint and do t think I can compress the cone anymore to raise it additionally.

I don’t have a torch to apply any heat to it, so maybe I also need to think about that.

Edited by mx5nut, 08 July 2021 - 07:01 PM.

[Spider]

As well as the Knuckle being corroded in to the Trumpet, the Trumpet too it sounds like is corroded in to the rubber cone. I like the way the removal of the trumpet is shown in the workshop manual as being removed by the hand !

 

You maybe able to remove the trumpet by levering it from behind down near the knuckle with a tyre lever or small crow bar. If it's really stuck, you may end up needing to break the trumpet in order to remove it.

[richmondclassicsnorthwales]

Tricky , but for the sake of about £3.50, buy a new pair of knuckles for £7.00 for 2 new ones

 

You have to put the trumpet into a vice to hold it, then try and crack it out.

 

Steel and aluminium - never a good mix

 

When you re- assemble, use some grease on the knuckle shaft. The aluminium normally cracks trying to get a knuckle joint out of an ally trumpet

[mx5nut]

Now I think I’m completely screwed. Was just in the garage working at it with a pry bar and the darn threads in the cone seem to have been rusted and gave way, so the center rod of the cone compressor popped out. There was a loud bang like the ball joints separating so I assume the threads in the cone are now gone and I’ll need a new center rod for my cone compressor.

What are my options now? Get a reciprocating saw and literally cut through the knuckle joint and the trumpet to get it out in sections? Now that the cone is uncompressed, the knuckle joint is almost back down in its socket in the top arm, which is why I am thinking my only other option is to cut sections out.

I am so attached to this car, but it is really giving me fits right now!

[richmondclassicsnorthwales]

You will have to take out the top arm.

 

The cone should be half goosed' so there should be not too much compression on the top arm.

 

You will have to release the top ball joint to do the job

 

It is typical as water has gone down the top , entered the cone, and in turn seized the knuckle in the trumpet' .and corroded the thread of the cone.

 

Undo the rear top arm bolt and the 2 x 1/4 screws on the front plate, and pull through the shaft. you may have to extract the radiator

[mx5nut]

Update: Determined not to go to bed feeling defeated by this car, I went back to the garage. My hack saw had one blade left and I thought I would give it a shot.

I was able to cut all the way through the narrowest part of the nuckle joint, which allowed me to then drop the ball part of the joint all the way down into the socket, and rotate the ball with the cut end enough to pull out of the socket. This then gave me the clearance needed to fully remove the top arm.

What I am now left with is the cone that is stuck up in the subframe, the trumpet that is seized to the cone. For me, this feels like a big win. Now I need to figure out how to dislodge the cone with the trumpet stuck to it.

Thanks so much to everyone who had provided feedback so far! All good points that has helped me keep at this.

[timmy850]

I managed to wiggle this out of the subframe as one unit. It was completely fused together

Attached Files

•  2883AFD3-40BE-49C1-9099-FCE4F9F9426F.jpeg   48.91K   9 downloads

[mx5nut]

I managed to wiggle this out of the subframe as one unit. It was completely fused together

On a side note, is there a certain post count that one needs to reach before being able to attach pictures? I tried twice yesterday and it never seemed to work.

I am going to continue to try and wiggle the cone out later today. I am wondering if there is a chance that the top of the cone that meets the subframe could somehow be rusted to the subframe, which could also be giving me trouble.

[timmy850]

Did you choose the file and then click attach? You should be able to see it on the preview before you post the reply

[sonscar]

The cone locates on a steel ring at the top of the tower.Fit a bar of some kind into the cross member hole and gently bash it with a big hammer.Use some finesse and it will come free.Do not be disillusioned perseverance will prevail,Steve..