Flyboy Dave

My Feedback: (21)

What's the best solvent to free up engines that are stuck with castor
oil that have been sitting for years ???

1200SportsterRider

I use this Corrosion X and some heat plus a day or two of soaking. I started buying this way back when Sheldon's was my seller of choice.

Jesse Open

Many different oils and solvents work well. Heat is the element that does the real work. Heat gun, propane, toaster oven etc.


A good soldering gun is very helpful for spot heating and freeing up gummed wrist pins, carb barrels etc. Especially carb barrels while still mounted in the plane.

My personal go-to oil is "Kroil" for most jobs For a solvent, Xylene solvent cuts castor better than Acetone, Laquer thinner etc. Just do not use solvents near open flames !

jaka54

Hi!
Heat is the most important thing to use! It doesn't matter what oil you use. But be prepared to replace all ball bearings!

1QwkSport2.5r

I use heat and acetone. Works well enough for me and fairly quickly too. Never tried Xylene. Might have to next time. Exotic sounding chemicals that I’ve never used make me a bit sketchy... Someone told me to use MEK (MethylEthylKetone) once, but after reading about it, I decided the risks weren’t worth it.

I like to use stuff I can use in my house where the risk of blowing my house up is low or nonexistent and my fingers won’t get frozen off at the same time.

Jesse Open

For sure, when I was a kid one of the fellows in school was working on his minibike in the basement. Tipped over a cup of gasoline and burned his house down. I generally avoid aromatic solvents for gummed engines.

The Safety Data Sheets for solvents are the primary source for handling instructions. They should be followed closely. Ventilation is almost always a factor as well as avoiding skin contact and splashing into the eyes etc.
Xylene and Acetone are found in the paint department at the hardware store.

Propworn

My Feedback: (3)

If I'm in a hurry heat works well if I'm not I find a good soak in fuel works well. All can be done outside no fumes in the house.
If you use Kroil look beyond the safety data sheets to the chemical fact sheets. I have used Kroil for years at work and at home there are some significant cautions in the chemical fact sheets that are not mentioned in the safety data sheets. Some of the chemicals are highly skin absorbable at all temp and when heated are even more toxic if you breath in the fumes. It is the best penetrating fluid I've used but please use it carefully.
For heat I had an old cheap portable bbq I set up outside, the one that uses those 1 lb bottles. 1/4 steel plate instead of a grill, set the motor on the plate and fire up the bbq. I have also used heat lamps and my latest is a repurposed powder coating oven from Princesses Auto. I have seen people ruin a motor with to much heat from a torch so I only use one as a last resort.

For soaking I find the last inch of fuel in the jug is likely to show signs of contamination so I save this in a marked fuel bottle to use as a cleaner/soaking agent. I open up the engine to let the fuel get to the internals and I try and pick a container and lid just big enough for the engine and pour enough fuel to cover the engine. A lid keeps the fuel from evaporating. Usually over time and gently working the parts the engine will free up.

Upon inspection if the motor is worth saving I install new bearings and seals the old stuff I feel is beyond the best before date.

Jesse Open

Also be aware if you are using especially methanol-nitromethane based fuel for soaking; it too is highly toxic and the same measures regarding skin absorption and inhalation of vapors apply.

So many gummed up globs today are barely worth cleaning anyhow.

Kweasel

My Feedback: (29)

Thats true, if the owner wasn't mindful enough to oil the engine after use then its probably in poor overall condition now. There are always exceptions, my experience is keeping me from buying a used engine ever again. They're seldom worth the cleanup hassle and bearing replacement.

erik58

My Feedback: (4)

I use rubbing alcohol and heat gun it works well it isn’t that toxic

Jesse Open

Whatever you know about well enough to handle safely.

Heat is the main element, the oil and/or solvent is secondary.


"Freeing up" and cleaning up are quite different tasks.

JPMacG

My Feedback: (2)

Being gummed up is actually a good thing in my opinion. It means that the engine was run on a high castor content fuel and is likely to be well preserved. If you are throwing out an engine because it is gummed up please send it my way. I will pay shipping.

Jesse Open

Too late, I tossed out over 30 bound up two strokes last fall. Many never saw castor. Pity so many people are under the impression that castor is the only possible cause for a stuck engine.
Not that I don't know how to free them up, not close. Just don't have any use for them after taking the effort.

JPMacG

My Feedback: (2)

The value of used engines is going up. They sell for enough on Ebay to make it worthwhile selling them.

I agree with you more on 4-strokes. There is a lot to go wrong with 4-strokes and parts are costly if available at all. 2-strokes, especially bushed 2-strokes, are almost bullet proof.

Flyboy Dave

My Feedback: (21)

Well I freed up this K&B .61 just using gasoline out side. I pulled
the backing plate and let it soak overnight. Then I used some
pliers and broke it loose... once it was loose I spun it with an air
ratchet and soaked it some more. I think the castor keeps the
internals from rusting. Then I blew it out and flooded it with oil...
I'll blow out the excess oil and put t back together... It should be OK.

Flyboy Dave

My Feedback: (21)

The carbs alone are worth $25 to 30 bucks each on E-Bay.

Jesse Open

Just the opposite here. I will expend time and money to restore four stroke engines. Two strokes for the most part are not worth either/or. Around here, with a few exceptions you can barely give a running two stroke away forget that if it needs work. Ebay has become a monster time and money waster.
I have given away a few engines here like Super Tigre 90, OS and a few Webra. But the stuck ones go in the trash regardless the make.

the Wasp

My Feedback: (1)

oh Gary, a Glow engine rather a 2st or 4st is a work of Art. if you are going to throw any more away, please let me know before you do.

Jim

1QwkSport2.5r

Don’t believe everything you read on the internet.

Jesse Open

I try to find homes for the unfrozen engines but for the most part anything frozen goes into the scrap box.
I sent that Italian Super Tigre 90 over to Okie, after I first offered it to you.

Sent Dave the Como 40, I think there are a few Webras still out there to check out.
Are you really interested in the frozen ones too?


PS (Edit)

Here are a few bits that didn't get tossed yet. An Enya 19v and a Webra 3.5 . Both turn over .

Let me know if you want them. Probably not made in China LOL!

A lot more to go thru so there will likely be quite a few more.

PM me your email and we can skip the $&@/:;(@
If you want the stuff, I will send it. You can believe that!

"Art" LOL !!!

the Wasp

My Feedback: (1)

I'm not interested in the smaller engines, I like the larger engines, 50 and larger. but yes the smaller ones are beautiful, classic mechanical art from days gone by. as for the ST 90 I knew Okie wanted it and figured he would use it well before I would.

Jim

Jesse Open

No problem there. How about a Kraft 61 in the box, with muffler?

1200SportsterRider

Any Webra SilverLines, I love them?

Jesse Open

Dave,
I think there is a Webra Blackhead .61.
IIRC it is in like-new condition but missing the carb.

1QwkSport2.5r

If there was a choice to throw a frozen stuck engine in the trash or add it to the collection, I would add it to the collection without any question. I’d offer to pay shipping too. I love stuck engines.