Removing a Trunnion with a siezed Bolt.

[billwill]

On one of my Trunnions the bolt securing it to the lower front suspension arms has seized in the bush so that taking off the nut and pulling, pushing and bashing with a hammer does not move the bolt so the trunnion cannot easily be removed from the Elan.

This topic is to move any discussion on this matter to here instead of the topic about rear-arm removal.

I inadvertently started a topic drift when I posted the following paragraph.

I still haven't solved my seized trunnion bolt. I am contemplating drilling a small hole sideways through the side of the trunnion, bush and inner sleeve of the bush and making a dent in the bolt itself, then squirting plus gas (releasing fluid) into that tiny hole and leaving if for a day or two. This will probably render the trunnion unusable, of course.
Which caused:

40 years ago Bill, I had the same problem as you, what I remember of it. My first car, a Sprint, must have failed its MOT due to play in the trunnion. On trying to remove the bolt to replace the bushes, the bolt was seized in the steel bush. Poor maintenance by the previous owner!

All I remember about getting the bolt out was bashing away with a club hammer, and it eventually gave up. I don't remember anything about sawing the bolt, but it was a long time ago. If you wanted to give that a go, undo the nylock about 4 turns and start bashing away on the nut. Do not bash directly onto the bolt head, as that will splay it, and it then will not pass through the steel bush.

This method may not work of course, depending on how corroded the bolt is in the bush, and cutting the bolt may be the only option.

Plenty of copper slip on your bolts on assembly folks will prevent this senario from happening in the future.

Good luck

Leslie

and:

Bill
Can you remove the hub off the trunnion, which means being able to get the top arm free from the hub and then unscrewing the hub from the trunnion. if so it may be easier to remove the trunnion and bottom arms as a unit so you can get them into a vice. Use a suitable socket to act as a spacer against the head of the bolt, on the other side loosen the nut a turn or two and then use the vice like a press to force the bolt through. At least in the vice you can get to the trunnion to apply some heat or penetrating fluid, easier than in situ on the car. Also it will enable you to work the bolt whilst trying to get some fluid in there.

It may also work if you leave the whole thing in the vice overnight under tension so the release agent can do its stuff.

An alternative is once in the vice, grind off the head of the bolt so you can either punch or drill the bolt out.
Tony

Please post any further comments about trunnion removal here not in the rear-arms removal topic.

[billwill]

It's been a while (Feb 2018) since I first encountered this stuck trunnion bolt problem. I has been mentioned in some other topics.
I've tried several approaches including bashing with a hammer, without success.

Here is a picture of an extractor that I made to attempt to push the bolt out:

But alas it was not strong enough and the 'straight-arms bent instead.

I've shelved the task temporarily, but will return to it later.

I have some new trunnions and some s/h uprights ready to install when I've sorted this seizure out.

[snowyelan]

Just remove the shock nut and bolt, the inner lower arm nut on the trunion bolt head side and slide the arm off with the trunion bolt and sleeve in the arm. This should leave you with the arm, bolt, sleeve and the seal outer shield as an assembly you can attack on the bench.

[billwill]

Assuming that the lower arm is not also seized onto the turret bolt, that sounds like a good plan. It's what Tony said above.

[snowyelan]

Actually quite different. The trunnion can stay in place on the upright. The bolt isn't seized in the arm, just the sleeve on the bolt, which captures only one of the arms. The second method Tony mentions cant be done. You cant remove both arms and the trunnion as an assembly, its captured by opposing pivots at the chassis.

[alan.barker]

Why not drill in centre of Bolt head bigger dia just to Bolt dia. This will remove Bolt head. The other end of bolt remove the Nut and put as many Washer as possible. Tighten Nut which will extract the seized Bolt shank.
Alan

[tonyabacus]

Bill, my apologies for the wrong posting, not sure why, but another of those old age factors is all I can offer!

Snowyelan, I think I may have confused issues as my posting to Bill ended up under a different posting about rear suspension, so not sure I understand your comment about the bolts, can you clarify, are you referring to the rear suspension arms?

However I must apologise Bill as I did forget that the shock absorber and caliper will need releasing, no need to bleed the brakes just secure the caliper away from the working area. The process for removing the front arms is clear from the workshop manual. Really you have two options, one after releasing the top suspension joint you can either unscrew the hub from the trunnion or leave the hub attached, but once on the bench unscrewing the hub will make access much easier.

One other thought Bill is heat, the problem usually is our hand propane torches do not get hot enough whereas a welding torch can apply more heat quickly. So perhaps you could take the assembly to someone with a welding torch and by heating the head of the bolt to something like a cherry red whilst applying a hammer blow at the other end(remember to leave the nut on), usually does the trick. You may also perhaps cycle this a couple of times by applying heat and then quench in cold water.

Another option may be once out of the car and easy to handle ask a local garage to put the assembly into a press and press it out without distorting the bolt and creating more problems. I think the key will be getting the assembly out of the car to open up your options.
Tony

[JonB]

I chopped it in half with an angle grinder (cutting disk). Soon came out!

viewtopic.php?t=40806&f=42&start=0#p285461

MR ZURKON DESTROY!

[snowyelan]

Hi Tony,

My reference is to the front trunnion removal. The problem with trying to free it while on the car is that the rusted bond between the sleeve and bolt needs to be broken, and there is no easy way to access it with heat, fluids etc.

There are quite a few pieces of the bushing assembly that can, and will stay with the trunnion itself when you slide the bolt, and the sleeve seized on it, out.

Undo the nut on the back of the trunnion pivot bolt.
Undo the nut on the lower shock bolt and remove the bolt.
Remove the inner front lower suspension nut.
Slide/pry the components in the next step forward as an assembly.
The parts that would come out together are the bolt, #26 front lower suspension arm, #22 outer seal cup, and #20 sleeve. #19 may come out as well, but is designed to rotate around #20 so should stay with the trunnion.

Doing it this way leaves you with a somewhat manageable rusted mess to attack on the bench.

[billwill]

I haven't rechecked, but I have a vague recollection that there is something in the way, that would make drilling the head off the trunnion bolt somewhat tedious/impracticable unless the assembly is removed from the car.

Heating the bolt seems difficult too, since it is in the centre of a rubber bush, which would insulate the heat if you applied the torch to the brass trunnion. Applying the torch to the bolt head and exposed thread would seem to be needed & I'm not sure that would do the trick.

Some of the suggestions appear to forget that the front lower arms are bent steel which forms a U shape around the head of the bolt, so grinding the head off the bolt would likely destroy the lower arm too.

At present I am waiting for warmer weather as trying to do suspension work inside my narrowish garage would be too cramped, it would be much easier out on my forecourt. There are possible snags with the ULEZ charges (I would have to put my non-compliant MPV off the front yard) and (as it might take more than a day, there a chance of meddlers/thieves messing with the Elan while it is exposed on the front yard.

[tonyabacus]

Snowyelan, with respect I think what you have said, is exactly what I said to begin with.
There is really only one way of dealing with this and that is on the bench, if the trunnion bolt is seized then you need to remove the lower arms and hub carrier and disc as an assembly to be able to get at the trunnion bolt to remove it.

Its therefore only a matter of releasing those items holding the hub carrier and lower suspension arms in place to be able to get it on to the bench. If you want more room to get at the inner lower suspension arm bolts then once the top suspension link, shock absorber lower nut, track rod end nut are free, you can spin the hub carrier and disc off from the trunnion (which of course will still be attached to the bottom suspension arms). This will give more access and once the inner lower suspension bolts are removed from the chassis, the lower suspension arms and trunnion can be removed to the bench.

Bill, do you have access or can you borrow a trolley jack, if so you may be able to draw the car far enough out of the garage to remove the parts and then carefully push the car back in on the jack so as not to compromise the security of the car. I use a length of 4"x2" timber on top of the jack to support the car on its chassis rails for such work without issue, that way you don't have to worry about the job taking longer than a day.

From your comment about ULEZ charges that you may be in the London area, so perhaps a local member of the forum could lend you a jack if you don't have your own.
Tony

[snowyelan]

Hi Tony,

I fully agree on the bench is far easier than beating on bolts while on the car, especially when the beating is cushioned by rubber inner arm bushings.

However, what I propose is not the same. You cannot remove the lower arms and trunnion as an assembly. The 2 inner pivots are on chassis studs, not bolts, in opposing directions. The front arm arm needs to move forward for removal and the rear arm to the back. You must remove the front and rear lower arms as separate pieces.

The possible flaws in what I propose is the inner upper front arm bushing being seized on the stud (decent chance of it), the trunnion bolt being seized in the lower back arm (very slim chance), and the trunnion bolt being seized in the plastic trunnion bushings (slim again, being plastic).

While my pivot sleeve was not seized, I did this procedure a few weeks back in order to re-grease the lower bushings. My proposal for repairing a seized sleeve is based on this.

[billwill]

I have the relevant jacking tools & axle stands & car ramps etc, that isn't a problem. It simply isn't very practical to do what you suggest i.e have the car half-in/Half-out of the garage, that just makes unneccessary hassle. It's far simpler to wait for warmer weather & do something about an Alarm in the front yard, if necessary.

The garage has a 2 inch triangular conclete ridge accross the doorway to prevent rainwater flooding into the carrage. It's not easy to get a trolly jack over that hump when fully loaded and first I would need to get the car out turn it 180 degrees & drive it in backwards anyway.

Don't worry about it. I will get it done, I've done front suspension work on this Elan before.

[tonyabacus]

Bill
Obviously that rainwater ridge was an unknown in my suggestion and of course will not make possible what I was suggesting. However I am sure once the better weather arrives it will enable you to get on top of the job, best of luck
Tony

[billwill]

Bill
Obviously that rainwater ridge was an unknown in my suggestion and of course will not make possible what I was suggesting. However I am sure once the better weather arrives it will enable you to get on top of the job, best of luck
Tony

Yes, it was a good suggestion, it just doesn't fit my environment.