Thread: V8 Non start after rebuild

Was hoping a real mechanic (rather than me) could give a better description about new motors verses resistance ..... But here goes .....

Originally Posted by sheerluck

was to remove the plugs and try spinning the engine over by hand from the crank bolt with a standard ratchet and socket.

.... Good stuff .... So long as nothing is hitting, all should be fine

Originally Posted by sheerluck

And it does feel very stiff. No obvious individual points of resistance, and generally the motor does feel quite stiff.

There will be a lot of resistance from a non started fresh rebuild ... There is a lot of resistance (friction) from the rings against the freshly honed bores ... You would be leaning 1/4 ... 1/2 heavy on the ratchet arm to turn it over .... (everybody's description of weight is different, and it's hard doing a internet thingy) ... so you may wanna expand a bit, on Your description of resistance)

if your using a "strong bar" and got the arm weight up to torque strength "grunts" ..... then something "maybe" wrong ... (Who built this motor?)

Originally Posted by sheerluck

Was it just a case of the new bearings, rings etc just giving too much resistance for the 12 year old starter (and it's 14 year old brother) to handle?

Correct .....

Brand new motors verses old parts don't mix well .... The motor will be tight and will kill off any old electrical parts in a flash .... This includes old starters / coils / leads / plugs, ect

Try the following ....
.... Install the starter motor ....
.... Leave the spark plugs out
.... Disconnect the positive and negative power lines to the coil (don't just pull off the coil spark lead)
.... Hold the throttle WIDE open ....
.... Get a mate to turn the motor over while your looking and listening at the motor.....


The method of starting the motor, when your not sure is the following ....
The first try of the starter is just a flick (of the switch) ... The next start is a 1/2 turn flick ... the next start is a full flick .... the next start is a 2 turn flick .... so on, & so on

With the plugs out. this will give a no compression resistance to the starter motor, and will give you the ability to hear and see your handy work


BTW .... With plugs out .... and using your starter motor turning the motor .... you can actually (using a timing light) check the timing position of the motor .... Trust me tho .... any where between 0 and 20 degrees setting will still get this motor to fire ...so you don't have to be bang on 3 to get this thing to move ass



When your happy .....
Install the spark plugs
Reconnect the coil
Start the motor





Cheers
Mike

Mike,

Many thanks for such a comprehensive post!

So, to start off.....an exact (or not!) description of the force needed:

I used a shortish ratchet (about 220mm from the centrepoint to the end of the handle) to turn the crank, so that I could simulate what force would be required by the starter trying to spin the flywheel.
In terms of my strength range, it was about 2/3 of the way up a single arm strength range. Not far before the cursing stage, but no where near the go purple in the face and make a noise like "......mmmmmmmmmmmmmkinell" stage. Could turn it with my weaker arm (I'm no 8 stone weakling, but no athlete either), but I could appreciate that a 12 year old starter would not not have the guts to spin it anything other than very slowly.
Using a longer (450mm) wrench with the plugs in was a 2 arm job and about 3/4 of the way up the strength range.

It did start to feel more loose, the more I spun it, which I'm taking as a good sign.

I did the rebuild. Only the second one ever I've done, but I like to think that I'm pretty meticulous, anal almost sometimes, but there is always the constant worry that you've missed a trick somewhere when you don't do this for a living.

I'll be getting the scruffs on again this afternoon, and will have a go at your suggestions.

Any chance your drive belt is caught up on one of the pulleys???? By the way a inhex/allen key socket in power steering pump pully makes turning engine over by hand easier job than using flywheel.

Originally Posted by sheerluck

It did start to feel more loose, the more I spun it, which I'm taking as a good sign.

Only you can see it ... But Sounds as tho it's "OK to go" to me ...


Mike

Mwahahahaaaaaaaaaaaaaaaaa......IT LIVES....IT LIVES!!

A million thanks to all who posted here. And a special thanks to all those who offered help and support by PM, offering phone numbers and on site assistance.

Finally, it goes. And it runs beautifully.

It was simply a case of new parts not playing nicely with the old, exactly as Mike 90 RR said. The new battery, the new starter and some fresh petrol siphoned out of SWMBO's Merc, along with a squirt or two of startyabastard and it went.

So 15 minutes at 2500rpm to bed it all in, and now it starts with half a flick of the key, the oil light goes off in half a second, and it purrs. No vibrations, no unusual noise, except there was some funny noises from the power steering pump at first (rectified by bleeding the power steering box).

Tomorrow, is brake bleeding and road test day, provided there are no leaks appear overnight. Currently there are none....woohoo!

Wish me luck!

Originally Posted by sheerluck

Mwahahahaaaaaaaaaaaaaaaaa......IT LIVES....IT LIVES!!

A million thanks to all who posted here. Finally, it goes. And it runs beautifully.

It was simply a case of new parts not playing nicely with the old, exactly as Mike 90 RR said. The new battery, the new starter and some fresh petrol siphoned out of SWMBO's Merc, along with a squirt or two of startyabastard and it went.

So 15 minutes at 2500rpm to bed it all in, and now it starts with half a flick of the key, the oil light goes off in half a second, and it purrs. No vibrations, no unusual noise, except there was some funny noises from the power steering pump at first (rectified by bleeding the power steering box).

Tomorrow, is brake bleeding and road test day, provided there are no leaks appear overnight. Currently there are none....woohoo!

Wish me luck!

Excellent news!!! Feels great doesn't it?

Now you can enjoy it


JC

Originally Posted by sheerluck

Mwahahahaaaaaaaaaaaaaaaaa......IT LIVES....IT LIVES!!

AND ABOUT BLEEDIN TIME ....


Make sure you keep a torch handy, and look at all the injectors for any fuel weeping

Originally Posted by justinc

Excellent news!!! Feels great doesn't it?

Now you can enjoy it


JC

Oh yes it feels good. I've spent a lot of time, and a fair chunk of cash on it, so now I have a Disco 1 with a rebuilt motor, and most other components in the engine bay brand new.

I hope it'll last a few years and a few trips off road.