Semi Seized Cam Followers

[JonnyPlus2]

Evenin' Lads

I have a Twink head that the DPO left in his garage shed so that I would not miss out on the fun of extracting the cam followers after they became corroded in. Having soaked them in my fave rust remover (50-50 acetone and auto trans fluid) and banging on them with a 4 pound sledge hammer using a piece of hardwood as a drift they are now un-seized.

Unfortunately, they aren't exactly free either. Has anyone been here before ? I reckon I could be bashing on the cam followers and soaking them in anti-seize for quite awhile before they loosen up, if they ever do. As always, thanks much for your invaluable help.

Regards,
Jonny B.

[rgh0]

Never had any stuck quite that bad!!!

All I can suggest is keep doing what your doing until they come free enough so you can grip the top lip with something and pull them out.

Some chill spray on the bucket and some gentle warming of the surrounding head with a hot air gun or hair dryer may also help increase the clearances and break them loose

cheers
Rohan.

[JonnyPlus2]

Hi Rohan,

Well obviously none of your Twink heads have had the advantage of several years in an unheated shed in Canada.

I shall carry on. What is this chill spray stuff, I've never heard of it. I can see how it could work though.

Best,
Jonny

[rgh0]

This is the stuff i use

http://www.henkelna.com/loctite-freeze-release-7008.htm

cheers
Rohan

[JonnyPlus2]

Thanks Rohan,

If this stuff is half as good as the ad says, it's the greatest invention since beer and that other thing that we like a lot. I'm getting some in the a.m.

Best,
Jonny

[rgh0]

Not quite as good as beer and sux ( as those kiwis say!) but it has sure helped me free up seized bolts and other components over the years. A bit of heating and cooling in combination with penetrating oils of your choice and patience.

I had to get the seized nuts that hold the windscreen wiper mechanism onto the body off a few weeks ago on my Plus 2, I don't think they have every been removed in the life of the car and they were stuck solid. After a few weeks soaking in penetrating oil and a spray with this and one came off. The other refused to move despite repeated treatments and in the end I had to get the dremel out and cut if of with a carbide tip .

cheers
Rohan

[chrisban]

Hi,

Have you tried apple cider vinegar, it'll gently eat the rust away and leaves the metal underneath untouched, beats any penetrating fluid/wd40 etc etc I've ever tried. Takes a couple of days to a week and you will probably have to keep re applying it unless you can get the follower lower than the head rim and then just fill the hole with it, or turn the head over and fill the ports with it (that'll probably work better). Then I guess gentle tapping both ways, patience, more gentle tapping, more patience and on and on lol.

If I really want to remove rust and free things a little quicker then I use Jayes fluid (drain unblocker about 70% hydrochloric acid), but it eats the good metal away too, so prolly a bit to aggressive for a twink head.

Those freezing sprays are ok for small nuts etc, especially if you have access to the whole nut, but doubt it'll get a follower cold enough, probably only cool the top and the stuck sides will laugh at ya.

atb.
Chris

[avro]

As you've already beaten the rusted cam followers to death with a 4lb lump hammer to free them up and you are going to replace them with new, there is a very easy way to remove them . It just requires a split second tack of mig weld to attach a small bolt, nut or similar to the top of the cam follower, allow to cool and pull them out with a pair of mole grips or pliers. If your worried about the slight possibility of bit of welding spatter that may attach itself to the surrounding components then protect them accordingly. I've had heads to overhaul with all eight followers seized and it takes but a few minutes with no risk of damage to the surrounding parts. A good soak with some penetrating will ease their removal. A small tack or two generates very little heat and will cool within seconds.

Nick

[JonnyPlus2]

Hi Nick,

Great idea !

I'm hoping to save the cam followers which is why I used a hardwood drift between them and my handy 4lb persuader. That being said, if they don't loosen up before I lose my patience I will use the Nick method.

On the other hand, I do recall that my friend Steve Broad had a cam follower break up at high revs which caused as much damage as one would expect so I shall ping him about that. Perhaps I'll just rip 'em out and be done with it.

Thanks much.

Best Regards,.
Jonny

[rgh0]

If they were firmly rusted in then the surfaces of the sleeve and the follower will both be to rough to reuse i think - so new followers and probably new sleeves will be in order.


cheers
Rohan

[avro]

Should you be able to get away with a light hone to the follower sleeve .001" thou oversize cam followers are available if required from QED.


Good luck

Nick

[Bud English]

I've had great results using my aircraft rivet gun to drive out things like leaf spring shackle bolts and the like that a heavy hammer wouldn't budge. Amazing what a couple thousand small, light, hits will do in a very short time. An air hammer with a straight drift would probably work just as well.

[avro]

I've had great results using my aircraft rivet gun to drive out things like leaf spring shackle bolts and the like that a heavy hammer wouldn't budge. Amazing what a couple thousand small, light, hits will do in a very short time. An air hammer with a straight drift would probably work just as well.

Hi Bud

From your comment I'm not sure if you understand the problem. Driving the follower out is not possible as the valve assembly is still fitted and the valve can't be released until the cam follower is removed . However the action of an air hammer on top of the follower and against the spring pressure could work quite well. It might loosen the follower within the sleeve quite quickly and hopefully it could then be pulled out a little easier from the top.

Nick

[rgh0]

Should you be able to get away with a light hone to the follower sleeve .001" thou oversize cam followers are available if required from QED.


Good luck

Nick

Hi Nick
You are a true optimist - the sleeves were probably worn to an hour glass shape when the head was stuck in a shed and probably now has pitting in the sleeves more than a thou deep. You would have to be lucky for a 1 thou hone to bring it back ---- but you never know until you measure it up I guess

cheers
Rohan

[avro]

Hi Rohan

Your probably right on both counts. Definitely an optimist.

All the best

Nick