Dismantling a very seized engine

[jonathanrippon]

Finally thanks to Sam Glover’s kind assistance I now have MUW554 safely ensconced in my garage. Remarkably the bodywork is better than expected, cosmetically dreadful but structurally quite redeemable.

I have started however with what I suspect will be the trickiest issue to rectify, the engine.

The car came with two engines, both in very poor condition, seized and with every indication of having been stored very badly.
My desire is to somehow salvage a good crankcase and crank because I suspect these are the most challenging parts to find.

One engine has a badly cracked crankcase however the other so far seems to have potential. I have taken the heads off it and removed the sump. The engine has had water in and is very rusty internally. It is seized pistons to liners and also the little ends have rusted up. I have managed to undo the big ends of two of the pistons and get the pistons moving slightly. Unfortunately the other two are in such a position I can’t reach the big end bolts.

Unseizing the remaining two pistons and their little ends is going to be impossible so I think I have only two ways forward:

1) cutting through the conrods of the stuck pistons which will allow me to rotate the crank to remove the clutch and flywheel so permitting me to unbolt the bellhousing and split the crankcase. Or:

2) Is the bellhousing matched to the crankcase? If not I was thinking of cutting it off to remove the clutch and flywheel with the crank still seized in the hope that this will allow me to split the crankcase. One appears less corroded in than the others and I hope I might get it moving.

Whilst option 1 is more straightforward it will be I think time consuming because I think I would have to use a junior hacksaw because using a powertool would risk damaging the crankcase.

I would value any advise from anyone who has dealt with engines so badly seized as these.

[Srenner]

Soak. DO NOT cut the bell housing. Motors were machined as a piece.

Basically the rust/corrosion needs to be removed. You can soak top down or bottom up or both over time. There are products made specifically for rusted metal all the way to home-brews, Coca-Cola or molasses. Soaking could take several weeks and still require some hefty blows to the piston top to budge things. Heat also helps break the bonds.

My very first Javelin motor was as you describe yours; unable to access the con rod bolts. After a week or so of soaking in diesel, one piston broke up under hammering and the other did loosen.

[jonathanrippon]

Thanks, that’s helpful. I will get a load of Aldi cola tomorrow and fill the crankcase in preparation for more hammering next weekend!

Wish me luck.

[Keith Clements]

You should also try some heat. Firstly to speed up the chemical reaction of the rust eater and just before attempting disassembly.
Put a wine fermentation heater or similar in the brew to start and then use a high volume gas (butane or natural) burner to heat up components.
I would not worry too much about the pistons/liners as it would be better to just get a new set from JCS. Save the con rods though.
The order I would do things in is this, some of which you may be able to do before soaking (as you have done). Loosening as much as you can to start with should help penetration of fluids. Your main issue is that the crank will not turn so clutch bolts and big end bolts are not accessible.
Remove clutch, flywheel, 7x clutch housing bolts, timing cover bolts, oil filter housing, timing cover, sump, big end bolts (although you cannot get at two at present), bolts along top of crankcase, 6 crankcase tie bolts (one under balance pipe). The crankcase should the separate. Perhaps soak the pistons in diesel for a week.
Then heat up crankcase halves. Try first to move pistons, as you are not going to reuse them put a wooden block on the top and a press or lump hammer could be used to dislodge. You could try doing this first after soaking to see if the pistons will move. You should then be able to press out gudgeon pins after removing circlips.

[jonathanrippon]

Thanks Keith!

fizzzzzz

[Chris Spencer]

Jonathan - One of the best anti seize fluids that has worked for me is a homebrew of ATF & acetone - mixed 50 / 50 and left for a suitable period - its not failed me yet - Chris

[David Kemp]

After a good soak, I would try spinning the motor with a large spanner on the front pulley.
With luck it will push the stuck pistons and liners out of the crankcase enough to undo the conrod bolts.
Patience is really needed with a stuck engine. You could also stand the engine on it's end & pour caustic soda down the bore.
Caustic soda dissolves aluminium & carbon. Extreme caution is needed as the crankcase is of course aluminium.

[jonathanrippon]

Thanks Chris and David, very helpful.

The issue with tipping stuff into the crankcase is that it gradually percolates out into the wheelbarrow beneath (worrying it is managing to escape via the waterjacket which I’m hoping is via the liner seals rather than anything more sinister) so my plan is to buy a load more cola and keep topping it up through the week then I might give it a day on each side with the atf/acetone mix down the bores.

Hopefully with all of that come next weekend with the application of heat and some percussion I might get things moving.

Unfortunately I have managed to shear the starter dog off in the crank which isn’t ideal

[Keith Clements]

I was going to say be careful you do not shear dog. Much better as there is more leverage is a large screw driver on flywheel teeth.
I would use a large plastic recepticle (builders mixing bucket) or a butyl/rubber pond liner over a brick rectangle.
As I said wooden block (or large copper hammer) on piston and big end should move it. You may even break seal at bottom of liner if there is only one piston still seized.

[Srenner]

Coca-Cola has a small amount of phosphoric acid, so check to be sure your other cola has that in it. Chris suggests ATF/acetone and that is a common home-brew that gets recommended often.

Might also try putting the motor vertically and filling just the bore as the rings are closer to the crown.

[Tony Fearn]

Chris suggests ATF/acetone and that is a common home-brew that gets recommended often.

A very interesting thread.
Should I already know what the acronym ATF is?
Tony.

[Chris Spencer]

Tony - ATF = Automatic Transmission Fluid

[Tony Fearn]

Thanks Chris.
I was asking for myself, but realised that perhaps others might not have known.
But now they do!
Regards to you both.
Tony.

[jonathanrippon]

Victory!

Definitely the rustiest engine I have ever dealt with. The crankcases need cleaning properly but, provides the head faces can be cleaned up sufficiently they should be serviceable.

[jonathanrippon]

This is the camshaft which shows how bad it was. The followers are still seized in the crankcases!