Hi From Down Under

[Gregted]

We emptied a can of WD40 on the motor and surrounding fixtures and someone suggest I look at veg oil and acetone instead, so I have attached some test results of this mix.


I've discovered that WD40 is a great water displacement but not so good on rusted parts.



One states that veg oil and acetone loosens rusted bolts with half the force required with WD40.


Interesting.


Also saw this video on refilling your old can. I am going to try it soon but Do so at your own risk.

https://www.youtube.com/watch?v=oUG5C_pQpp0

[skipperpete]

The “new release” of WD 40 products is called the “Specialist” range and fixes that problem of drying out, I’ve tried 3 of the new release products, lithium grease, fast release penetrant and silicone, all seem to do what they’re supposed to but at a higher cost..... I got mine from Bunnings hardware but the Supercheap and Autobarn stores have em too. I like ATF for easing up stuck pistons, seems to work ok but I’m not keen on having acetone around. I recently needed to get 3 seized pistons out of a shibaura and they were stuck tight so rather than try and whack em out I drilled and tapped the crowns to accept ½” UNC threaded rod and used my liner puller bridge as the top support. I soaked em for a day and they came out ..... not easily!!.....but I did avoid damaging the conrods and bought a rebuild kit from Parts4engines with oversize pistons then got the block rebored to match them.

[Jim Cate]

FWIW:

Penetrating oils have their limitations in situations where oxide products have expanded to the point where mere lubrication is not adequate for release... as seems to be the case here.

There is an alternative method for release which alters the chemistry of the oxides to accomplish the job. I'm not gonna try to explain the process because I'm no chemist, but I have used this product successfully in the past. It is available here in Oz and IMO, worth a try in getting that piston out!

https://www.blackwoods.com.au/reducteur/b/558518

Good luck!

Jim

[Wotname]

^^ Jim is correct. Reducteur is good stuff, especially for steel on steel corrosion (stuff rusted together).

[Gregted]

Great news. The piston is out.
I used a 1 inch pipe across the mounting bolts for the gears to the flywheel and belted the pipe with a block splitter.

Only broke 1 bolt and bent another so we'll replace those before the rebuild. No flywheel threads were damaged in the making of this movie..

Piston was caked with rust and scum but cleaned up nice on the brass wire wheel. Rings are stuck fast in the grooves but I've got it soaking in some olive oil/acetone so we'll see how that goes.

There is a chip in the top of the piston but it is above the compression ring so if the rings come out ok, we might reuse it. Depends how much a better/new piston is.


The bore looks really good. A slight lip where the piston was stuck and the standard lip at the top of travel but those should hone out nicely.


The next good news is that the hand crank shaft now turns the motor over.

Further good news is that the water pump impeller looks ok.

Motor is cleaned up and flushed out. A coating of engine oil sits on the bore waiting for the hone.


The mixing elbow cleaned up a treat but we'll decide later if we are going to replace it with a stainless diy elbow.

[Wotname]

Great news
It will be running again in a week

[Compass790]

Glad you beat the bstd!
Have you measured piston diameter? It looks more like erosion from water leaking down on the the piston on the exhaust valve side than a chip to me. Liner pic out of focus but if it is with spec for diameter you good there.

It isnt that expensive for an aftermarket piston & rings, tho it will run with that one I'd be tempted to replace it. The outlet end of the mixing elbow doesn't look too flash, I'd go for the diy s.s. mixing elbow as you risk repeating the problem but yr risk, yr call.


Looking fwd to next update. Thanks for the reducteur tip Jim Cate & spraycan vid.Gregted

[RaymondR]

You might be lucky to get another 10-15 years out of that piston and about the same with the mixing elbow.

[Fore and Aft]

What about a bit of JB weld on that piston corrosion? Looks like a few YouTube videos about the subject.
I used JB weld to fix a hole in my car fuel tank and that stuff is impressive. After 2 years it is still not leaking.
Cheers

[Gregted]

Originally Posted by Compass790

Glad you beat the bstd!
Have you measured piston diameter? It looks more like erosion from water leaking down on the the piston on the exhaust valve side than a chip to me. Liner pic out of focus but if it is with spec for diameter you good there.

It isnt that expensive for an aftermarket piston & rings, tho it will run with that one I'd be tempted to replace it. The outlet end of the mixing elbow doesn't look too flash, I'd go for the diy s.s. mixing elbow as you risk repeating the problem but yr risk, yr call.


Looking fwd to next update. Thanks for the reducteur tip Jim Cate & spraycan vid.Gregted

Have not measured piston diameter yet.



I thought possibly water damage as well as that is the bottom of the bore where the water would have been flowing/sitting.


You're right about that outlet on the mixing elbow. We might reassemble it just to get it running and diy another elbow for longevity.


We intend to renovate the interior and move the sink from above the motor and across the cabin to the port side and make a box seat above the motor so we can just lift it off for repairs/ mods.

[Gregted]

Originally Posted by RaymondR

You might be lucky to get another 10-15 years out of that piston and about the same with the mixing elbow.

Hope so. That would see us out for that yacht I think. We are already looking at maybe a 40 footer for the extra room and off shore sailability.


This was too good a buy to pass up and it was 3 mins drive away.

[Gregted]

Originally Posted by Fore and Aft

What about a bit of JB weld on that piston corrosion? Looks like a few YouTube videos about the subject.
I used JB weld to fix a hole in my car fuel tank and that stuff is impressive. After 2 years it is still not leaking.
Cheers

Hadn't thought about JB Weld yet. I don't know how thin that edge is.


I have played around with JB in the past and I saw a vid of a bloke who replaced the whole top of a lawnmower motor with solid JB and it ran fine, so amazing stuff alright.

[Gregted]

A little update on the piston/ring removal.

I boiled the piston for 30 mins and that did nothing.

I watched some vids on electrolysis and thought that might be worth a go.

After 1 hour, I removed the oil ring but unfortunately it came out in about 15 pieces.

Have been soaking the piston in some baking soda and water with a battery charger supplying the 12 volts and tried some sacrificial steel plates for a few hours and then switched to aluminium but so far the compression rings won't budge.

The piston has a buildup of something after each hour but that cleans off easily.


The first buildup is after 2 steel plates and the second is aluminium.


I might leave it in overnight.

[RaymondR]

Originally Posted by Fore and Aft

What about a bit of JB weld on that piston corrosion? Looks like a few YouTube videos about the subject.
I used JB weld to fix a hole in my car fuel tank and that stuff is impressive. After 2 years it is still not leaking.
Cheers

Nope, don't put anything on it since it might break loose and do serious damage in the cylinder bore or head.

The material loss does not go down into the ring groove so it's only effect is to slightly increase the un-swept volume and slightly decrease the compression ratio. Should not be a problem.

[Wotname]

^^ While I don't have any hands on experience with using stuff like JB weld on a piston top, I would agree with Ray's advice; it sounds sensible.