Hello,
I cannot crank the motor. I just hear one click. With the battery I used first, tension went to 6V so I decided it was dead. I connected a 60Ah 600A batt.(which functions well on a Ford Diesel 2.3L) without success: just a click.
I tried to turn the cranckshaft with a 25cm long ring tool and it was very hard but in a few minutes I managed to turn it 360 °. Car has been standing 7 months unused. I have no larger battery at hand to test. My question is difficult.
Can the motor be seized, even when one can turn it around (but very hard, I had to hang on the 25cm ring tool; estimated force about 45 Kg). I also took out the plugs and added 5 milliliter of motor oil in each and let it stand for 1/4 h., but there was no real difference when trying to turn the crankshaft.
PS I just remember that the motor was hot last time I drove it (about 100°C) but without seizing (that time, 7 month ago). I even restarted it a few hours later without problem just to put it in the garage.

 

Yes, and no! Not much of an answer, huh?


1. Hand turning a big engine isn't easy. The fact that you can turn it all the way around is a definite+.


2. Are you trying to turn it by hand with all 12 spark plugs removed?
You might also slacken the drive belts to lessen the load.
Were the plugs out when you tried to turn it via the starter and big healthy battery?


3. If yes to the above, I say move to a starter issue. Electrical, mechanical or both.


for now, I'll stop there.


Carl

 

Not sure what a 'ring tool' is. But 25cm - a bit less than 10 inches--- is a bit small to hand turn and engine. I typically use a 30-40" lever/bar/tool.

If you can turn the engine by hand, even with difficulty, then the starter motor ought to do the same.

Let's hear what others say but I'm wondering if your starter motor has died

Cheers
DD

 

2: yes 12 removed not much difference than when not removed; no to second question

 

25cm long tool (one side is gable other is ring) as herehttps://www.gereedschapland.nl/produ...utel,-set-inch
Thanks for sharing yr experience.

 

Normal.

Like Doug I use a 24"- 30" breaker bar, and plugs in or out, no matter.

I suspect loose, or tarnished battery cable connections, especially the firewall connectors.

Next would be the White/Red heavy wire from the starter relay TO the starter solenoid. There is a spade joiner, just near the trans dipstick, and it will be grubby, or worst case, seperated, COMMON.

Solenoid internal connector disc is AWOL, NOT common, but it happens with age.

600cca is plenty of oomph.

 

What's that "firewall"?
Thanks for info.

 

UM, the steel panel between the engine bay and the passenger compartment.

Your battery is in the engine bay, and probably on the RH side for a LHD car.

The +ve cable goes from the battery TO the firewall connector, and would be under a rubber cover, and will have another large battery cable included, that travels to a same connector on the LH side of the engine bay.

Also on the RH connector is a battery size cable that goes TO the large connector nut on the top of the starter solenoid.

Thats the simple path of teh power circuit.

BUT

Without a GOOD earth path, there is no activity.

The V12 earth path is fickle at best. Look at the LH engine mount, there will be a braided cable travelling around that bracket TO the suspension cradle, then a 2nd braided cable from the cradle TO the chassis. These are 99% all crudded up, and a lousy earth path. Sooooo, remove them, clean them and the mating surfaces, and reattach. If in doubt, run a 2nd earth strap, a simple battery cable with an eye terminal at each end. I run from any easy to get at sump bolt and the rear bolt of the cradle V mount, thus supplementing/by-passing, the factory fiasco.

 

Other thing to note is that i read somwhere that one must never turn the V12 engine the wrong way, only in the direction of normal rotation or damage can occur to the timing chain tensioners.

 

Thanks, I read it too. Its because of damage to the MPS when turning left.

 

MPS, ????????

Damage to the $600 plastic tensioner boomerang is REAL. Some get away with it, most do not.

 

1. Go to the battery cable paths. Begin with the + post on the battery. Remove it and the other end at the post on the bulkhead between the engine bay and the cabin. Clean those connections and lube. Now from that post on the bulkhead down to the solenoid on the starter. Clean and lube that as well. I used bulk head as another name for fire wall.
'
In hopes of clarification of that nomenclature thing.


2. Now to the - post on the battery. On my car, it goes to the wing wall. Clean and lube each end.


Now, as Grant says, find the cable that connects the engine to the chassis. Clean and lube it.


In USA speak we call them combination wrenches. Open end on one side, box on the other. We also have box on both ends. Usually one size difference. they come in various lengths, stubby to longish!!


The breaker bar used with a socket is aptly named. Lots of leverage to get things moving.


If all that doesn't get a crank, come back. We can go further.....


Carl

 

Thanks, As soon as tests done, I'll post again.

 

Good on ya Carl, I forgot that damn word "Bulkhead", thanks.

Then V12 kicked in, and firewall sat better, they do tend to flare up from time to time, HA.

 

Flare up? leaking fuel only or other reasons I should watch?

 

I think having read that in that case positive pressure can come on the MPS when throttle is closed. This would cause the metal membrane to break...

 

Yes, fuel leaks. Leaky fuel hoses, decrepit from old age and heat, most commonly.

Cheers
DD

 

MPS still no idea what that is. PreHE had a MAP sensor on the radiator panel, and nothing will happen to that either way the engine is rotated by hand. No more than the same sensor mounted inside the ECU of a HE system.

Nothing of a membrane in a V12 system that I remember that could go hissy from rotating the engine backwards?????

Just the slack side of the timing chain snagging on the top lip of the tensioner, and snapping the pivot off at the bottom, oops.

 

Workshop manual calls it manifold pressure sensor (MPS), so we are talking the same device..