Author Topic: Stuck seat post in an 88 Haro Master (Read 2617 times)

tfi_friday · « **on:** November 08, 2018, 07:41 AM »

Hi,

I recently picked up an '88 Haro Master that had a stuck seat post. I knew it was stuck well after the previous guy tried with the LBS to remove the post and failed.

The LBS effort to remove the post resulted in a crushed GT post.. shame, but at least I don't have to have any guilt conscience about trashing the post to get it out.

So now it was my turn:

tfi_friday · « **Reply #1 on:** November 08, 2018, 07:46 AM »

First though was how hard could it be...

So I started soaking the tube in Automatic Transmission Fuild. I stuck a cork in the end of the seat post and filled up the seat tube from the BB till it was full.

Occasionally heating it up to see if that helped with getting the oil deeper into the space between the seat post and tube.

Gave it a few days then tried the vice again... and again... and again.

Snap! The seat post torn off... Thankfully I was still left with plenty above the seat tube.

tfi_friday · « **Reply #2 on:** November 08, 2018, 07:50 AM »

Plan B - The slide hammer

So I drilled a hole in the post and attached a u-bolt, then attached a slide hammer to the u-bolt with a chain.

Spent an good hour whacking on it... to the point the chain even snapped.

Tried some more with the slide hammer directly connected to the u-bolt before I gave up..

tfi_friday · « **Reply #3 on:** November 08, 2018, 07:54 AM »

Plan C - the Pulling Jig

Next idea was to make a Jig and to be able to pull the post out under tension using box section and a threaded bar...
Something like this:

So welded it all up and tightened it up and gave it a try... How could this fail!!

It failed....

In2bmx · « **Reply #4 on:** November 08, 2018, 08:15 AM »

Good effort Alan.

Glad you finally got the thing out

tfi_friday · « **Reply #5 on:** November 08, 2018, 08:18 AM »

Despair and frustration started setting in... to trimmed the post down again plugged it up again and filled it up again with Citric Acid for a day then ATF again.

I stuck all this on the Rad facebook page and the Steve Animal sent me a PM with a tip on how he does it with a strengthened hacksaw blade and using the feeling to know when he was through the seat post and not the set tube.

I didn't have the materials he suggested at home, but I did have a small metal bar, so I figured I could just tack the metal bar on to the hacksaw blade.

Then I realised I could use the metal bar as a depth guage... Once the metal bar touches the inside of the seat post the hacksaw wouldnt cut any further so I'd be sure not to cut into the seat tube instead of just the seat post.

Once the blade wouldn't cut I his the top of the post with a mallet!

IT MOVED!!!!

I drilled a new hole in the post and stuck the u-bolt into the vice and started twisting with the frame.