De-carb question.

[BillP]

Re: De-carb question.

Not to be confrontational either but I've used hair dryers to get stuck bolts loose on outboards and model engine parts. I've also used steam irons to do it. That was before I bought a heat gun. I don't heat the bolts either, I heat the surrounding aluminum. Sometimes I put an ice cube on the bolt head right after heating the area around it too. <br /><br />Torches are best used on steel to loosen bolts. Aluminum can go from hard to liquid in a milisecond when using torches. If you don't know how to use them it could ruin your day. It only has to happen one time to make you a believer...I'm a believer at the cost of an Evinrude 15hp lower unit that had a stuck drain plug.

 

[steviecops]

Re: De-carb question.

BillP<br />Are you talking about oxy acetylene, butane or propane torches?<br /><br />I was told that propane couldn't make the aluminium hot enough to melt it, and that you only need be careful with oxy acetylene.<br /><br />Following that advice, I used a propane/butane mix on the casing on my lower unit to get out the stuck bolts. I kept the torch going on the casing around the bolts for 1-2 minutes at a time and all it did was scorch the paint.<br /><br />Was I just lucky, or is propane/butane safe to use?

 

[BillP]

Re: De-carb question.

I used a portable hand held propane torch like you buy at the local hardware store and it did melt a button size area on the lower unit. I held the torch on the area a minute or two before it liquified the aluminum. I don't remember the torch setting. The aluminum surface flashed a blue color just before the meltdown. It happened in a second or two. The motor was a 1956 15hp Johnson. Maybe new motor materials are less sensitive to this problem and it isn't an issue now.<br /><br />I don't know the answer to what gases melt aluminum but what happened to me is fact.

 

[steviecops]

Re: De-carb question.

That must be a terrible feeling Bill, watching your motor liquidise in front of your eyes! <br /><br />Any more thoughts from anyone? Has anyone else had problems with melting aluminium casing on their motor?

 

[BillP]

Re: De-carb question.

It definitely made an impression on me...it happened around the late 60s and I still remember it like yesterday. It was one of my first lower unit takedowns.