Please visit the Club's website https://www.dloc.org.uk/ to join. Visit https://www.dloc.org.uk/adhoc to DONATE towards the cost of the forum.
Please don't post someone's email address to avoid it being harvested by spambots and it's against GDPR regulations.
Always look at "ACTIVE TOPICS" to see all posts in date & time order as they are sometimes moved; or look at "Your Posts".
Please add Reg. nrs. when posting a photo or anything about a car as this will help searches. Don't add punctuation next to nr. as this negates search.
CHANGED YOUR EMAIL ADDRESS since registering?, click your username and check your address in User Control Panel, Profile, Account Settings.
If you want help to register, use "contact us" at page bottom for help.

DB18 Seized Engine

Post Reply
Drastic_baloney
Posts: 4
Joined: Fri Jan 19, 2018 5:07 pm
Location: Okehampton, England

DB18 Seized Engine

Post by Drastic_baloney »

Hi, I'm starting to look into restoring my DB18, which has been sat for about 20 years. The engine seems seized, and I've tried the various tricks of hot oil in the spark plug holes and whatnot, but no luck. When I bought the thing (as a non-runner), I was playing around with the gear selector and depressing the selection pedal, curious as to how it all worked, and it seemed to lock something up. The selector now won't move, so I was wondering if I've caused some sort of lock-up in the gearbox and that could be preventing the engine from turning? It's the Wilson pre-selector, in case other gearboxes were available for the model.
The rear wheels spin freely, without the other side turning, so the back of the gearbox is spinning okay. I've used an endoscope to look in at the cylinder heads, and it doesn't seem too bad in there, which is why I wonder (somewhat optimistically) if the problem is the gearbox.

Any thoughts would be appreciated.

Cheers,
Keith

Norfolk Lad
Wise Man
Wise Man
Posts: 713
Joined: Wed Feb 10, 2016 8:23 pm

Re: DB18 Seized Engine

Post by Norfolk Lad »

Fluid flywheels drives the box so not stopping movement until it reaches 800 plus revs, firstly check valves are free remove rocker cover and test all valves move.
Look at push rods they will bend if valves are not moving so might be damaged now, starter motor could be engaged and stuck so check that.
Have you tried to start car before and are you using starting handle.

Drastic_baloney
Posts: 4
Joined: Fri Jan 19, 2018 5:07 pm
Location: Okehampton, England

Re: DB18 Seized Engine

Post by Drastic_baloney »

Norfolk Lad wrote: Tue Jan 23, 2018 7:37 pm Fluid flywheels drives the box so not stopping movement until it reaches 800 plus revs, firstly check valves are free remove rocker cover and test all valves move.
Look at push rods they will bend if valves are not moving so might be damaged now, starter motor could be engaged and stuck so check that.
Have you tried to start car before and are you using starting handle.
Ah, that's useful to know, I'll deal with the stuck selector when I come to it, if a running engine doesn't solve it.
I've started taking the head off and have removed the pushrods already, and it was all reasonably free. I've tried starting it by shorting the starter motor with jump leads and it just sparks, with no clicking from the solenoid, so you could be right about it being stuck. I've tried the starting handle but it's stuck solid, as is a socket and a breaker bar. I've already removed the seized water pump, so I'll give removing the starter a go. Cheers.

Norfolk Lad
Wise Man
Wise Man
Posts: 713
Joined: Wed Feb 10, 2016 8:23 pm

Re: DB18 Seized Engine

Post by Norfolk Lad »

The old trick with a stuck starter was to put car in gear and rock engine backwards, sadly not possible with fluid flywheel if it is starter you may have removed head when not needed.
But guess you will get a good look at the cylinders and can clean everything even the valve can be done, let us all know how you get on lots of help on here. :D :D ;)

Drastic_baloney
Posts: 4
Joined: Fri Jan 19, 2018 5:07 pm
Location: Okehampton, England

Re: DB18 Seized Engine

Post by Drastic_baloney »

Aha, quite possibly, we live and learn eh. I shall report back once I've investigated further, hopefully there's life in her yet!

Drastic_baloney
Posts: 4
Joined: Fri Jan 19, 2018 5:07 pm
Location: Okehampton, England

Re: DB18 Seized Engine

Post by Drastic_baloney »

No dice, the starter motor is spinning healthily, so it is an old-fashioned seized engine. I haven't completely removed the head yet, but I saw a suggestion of hitting the cylinder heads with a block of wood and a hammer, so I'll give that a go.

Phillmore
Wise Man
Wise Man
Posts: 847
Joined: Sat Feb 13, 2016 1:25 pm
Location: Worcestershire Herefordshire border

Re: DB18 Seized Engine

Post by Phillmore »

The gearbox problem is possibly a false neutral situation caused by moving the selector at the same time as pressing the gear change pedal. If the pedal came up with great force and is very stiff to push down then that will be it. Easily remedied - select a gear and push down very hard on the pedal and normal service should be resumed.
Andy

1954 Conquest Mk1, 1956 Conquest Mk2, 1957 Conquest Century Mk2, 1955 Austin A90 Westminster

Norfolk Lad
Wise Man
Wise Man
Posts: 713
Joined: Wed Feb 10, 2016 8:23 pm

Re: DB18 Seized Engine

Post by Norfolk Lad »

Might be possible to use the starter ring and a bar to turn the flywheel gives you more leverage, just depends how stuck things are try working it both ways.

Stan Thomas
Wise Man
Wise Man
Posts: 795
Joined: Sat Feb 13, 2016 2:14 pm
Location: Penkridge. Staffs.

Re: DB18 Seized Engine

Post by Stan Thomas »

Remove the head, remove the valves and clean the stems - as they tend to stick after a very long period of standing. Don't just start up the engine if that could be the problem and you manage to get it going as you will score the valve guides etc.

With the head removed, pour a small amount of diesel into each cylinder and leave it to soak past the pistons - as likewise, your problem will almost undoubtedly be the piston rings have siezed for the same reason.

Keep us posted for more suggestions!

Post Reply