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Freeing a seized engine
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Rick
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Joined: 27 Apr 2005
Posts: 21021
Location: North-west UK

PostPosted: Thu Dec 27, 2007 10:40 pm    Post subject: Freeing a seized engine Reply with quote

Ok, as mentioned elsewhere, I plan to start freeing off the engine in the grey ute. So far I've established that there is a little movement when I grab & try to rotate the bottom pulley. I found a starting handle that fitted, but no more success so far. I've only just started on this, so far:

- brake fluid down each plug hole, followed by neat (not aerosol) WD40
- rocker cover off, and WD down each valve in case one or more is stuck

Other thoughts:

- try a drop of diesel or coke down each bore
- maybe check the mains/big ends in case it is stuck there (I can't remember what the oil was like on the dipstick, so that'll tell me something about the bottom end I suspect)
- remove the head for a closer look at the state of the bores

Any other brilliant ideas to try if none of these work?? preferably non-destructive Wink

RJ
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Various 1920s-1960s - Austin, Morris, Commer, Dodge etc.
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peter scott



Joined: 18 Dec 2007
Posts: 6177
Location: Edinburgh

PostPosted: Fri Dec 28, 2007 12:06 am    Post subject: Reply with quote

Hi Rick,

If you've tried all the easy things then the next step has to be removing the crankshaft. Once you've done that then you are able to address each piston in turn without the others adding assistance to the immoveable one you are working on. Get a nice big block of wood that covers most of the piston area and hit it with the heaviest hammer you've got. Most of the seizure will be from the top rings and the relationship between piston crown and top rings is pretty strong so don't worry about damaging the pistons.

Good luck,

Peter
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peter scott



Joined: 18 Dec 2007
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Location: Edinburgh

PostPosted: Fri Dec 28, 2007 2:45 pm    Post subject: Reply with quote

More...

I know that taking the head off and dropping the crank probably sounds a load of work, but if the engine is seized due to lack of use then it will most probably be because of moisture corroding the rings. If you don't remove the pistons from the block then the rings will probably remain seized in their grooves even if you manage to free them from the cylinder walls. Clearly this will result in poor compressions and high oil consumption.

Apologies if this is in the suck eggs category. Neutral

Peter
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Uncle Joe
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PostPosted: Fri Dec 28, 2007 4:26 pm    Post subject: Reply with quote

My own method is to drop the oil, then remove the plugs and use ATF. Leave it over a weekend or longer if possible.

Then, as Peter says, remove the head, spray on WD40, and warm the tops of the pistons. If it is possible, remove the rods from the crank. make sure that its possible to get hold of the spares that you need before this though. Then, gently, place a block of wood on the pistons, and tap them. Note the word GENTLY!

Bet you its nr:3 cylinder thats stuck.... Very Happy
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ukdave2002



Joined: 23 Nov 2007
Posts: 3491
Location: South Cheshire

PostPosted: Fri Dec 28, 2007 6:35 pm    Post subject: Reply with quote

peter scott wrote:
I know that taking the head off and dropping the crank probably sounds a load of work


Presumably Rick you will be taking the head & crank off at some stage anyway?
So Peterís advice should save time in the long term, as you wonít for example be hammering non seized pistons Smile
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Uncle Joe
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PostPosted: Fri Dec 28, 2007 7:51 pm    Post subject: Reply with quote

As long as it is possible to remove the rods from the crank, then there is no need to remove the crank. Doing that will also show which piston(s) are seized or not...

UK: Note that I didnt say ''hammer'' but ''tap gently''
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peter scott



Joined: 18 Dec 2007
Posts: 6177
Location: Edinburgh

PostPosted: Fri Dec 28, 2007 8:06 pm    Post subject: Reply with quote

Unfortunately you wont be able to disconnect any of the rods if there is more than one pistion seized (unless they are non-opposing pistons). That's why it usually comes down to a need to remove the crank.

Peter
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ukdave2002



Joined: 23 Nov 2007
Posts: 3491
Location: South Cheshire

PostPosted: Fri Dec 28, 2007 10:13 pm    Post subject: Reply with quote

Uncle Joe wrote:
UK: Note that I didnt say ''hammer'' but ''tap gently''


UJ.. Noted, my father in law manages to gently tap stuff and sort it when I would have resorted to a lump hammer!!! guess that expirience!

Dave
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buzzy bee



Joined: 23 Nov 2007
Posts: 3397
Location: South Cheshire

PostPosted: Fri Dec 28, 2007 10:24 pm    Post subject: Reply with quote

Hi

I have allways given things light taps, but have allways been told off, give it a good whollop they say, I gues that is the agricultural, blacksmithing and boiler making trades! hehe

New years resoloution is to be more heavy handed, think I may succeed this year! Laughing Wink

Cheers

Dave
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Penman



Joined: 23 Nov 2007
Posts: 4128
Location: Lancashire

PostPosted: Sun Dec 30, 2007 9:16 pm    Post subject: Reply with quote

Hi
Can you lift the front enough to get a longer lever onto the starter handle receiver's Hexagon?

You might even be able to Tap/Wallop the lever, if you can get one on there.
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woljags



Joined: 26 Dec 2007
Posts: 31
Location: Maidenhead

PostPosted: Mon Dec 31, 2007 5:32 pm    Post subject: Reply with quote

the best way to deseize an engine is to remove the plugs and fill the bores with diesel topping up over a 2 weeks period.it works every time i try it
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ukdave2002



Joined: 23 Nov 2007
Posts: 3491
Location: South Cheshire

PostPosted: Wed Jan 02, 2008 9:33 am    Post subject: Reply with quote

Apparently F1 engines are siezed when cold & before they can be started hot coolent is pumped through and warm oil added, it did strike me that heat is great way of freeing other siezed components, don't know how practical it would be to get soime heat in your seized block, just to ease things on.

Dave
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peter scott



Joined: 18 Dec 2007
Posts: 6177
Location: Edinburgh

PostPosted: Wed Jan 02, 2008 10:53 am    Post subject: Reply with quote

Heat is certainly very good but for an engine block you do need an awful lot.

Applying it on the outside is a bit soul destroying as the separation of the water jacket is unhelpful. Applying it directly into the bores is better but you still have the spinning plates problem keeping them all hot and of course you don't know which cylinders are seized. Ideally you'd want to heat the walls and cool the piston. I haven't tried using freezer spray but it might help.

Peter
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woljags



Joined: 26 Dec 2007
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Location: Maidenhead

PostPosted: Wed Jan 02, 2008 10:34 pm    Post subject: Reply with quote

why not try warm water in the cooling system
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47p2



Joined: 24 Nov 2007
Posts: 2002
Location: Glasgow

PostPosted: Wed Jan 02, 2008 10:54 pm    Post subject: Reply with quote

The seized F1 engines are not due to rust and lying idle for many years, but due to very tight tolerances when built, therefore warming up would expand parts enough to losen off and turn over.

Warming an engine that is seized due to lying idle and rust would not in my opinion release it as the rust is the key factor here.

Diesel down the bores would be my prefered method and keep topping up for a couple of weeks.
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