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Locking engine, when gland nut tight.
duncombemu - September 20th, 2003 at 08:02 PM

This problem has got me beat.
I had a leaking crank shaft oil seal, which I've now replaced. I've set the Crankshaft end play to .0032" and I've screwed the 'Gland Nut' into place, but when I do it up to only 25 ft lb torque, the whole engine won't turn over. Undo the gland nut until it's really loose (hand tight) and the engine will turn over 'like new'. Do up the gland nut again to 25 or more ft lb's and the engine stops, unable to be turned over. We all know that torquing up the gland nut to 217 ft lb's is what is needed.
What am I to do? Can someone let me know what's wrong and how I can fix it.
Regards,
Mark:thumb


11CAB - September 20th, 2003 at 08:20 PM

What was the endfloat before you took the flywheel off? How do you know what the endfloat is now if you cant do the flywheel nut up? If you've changed shims, it is possible that one or more has a groove in it which can give a false reading.


duncombemu - September 20th, 2003 at 08:26 PM

I did up the gland nut to the specified torque (approx. 217 ft lb) and measured the end play. The crankshaft will still move end for end, so I can measure the end play. It just won't turn over. It's like it's been locked at the flywheel or something.
Mark


1303Steve - September 20th, 2003 at 09:57 PM

Hi

I dont want to alarm you, but your rear main bearing may be flooged out and is actually moving back & forward in the case. This the only explanation I can think of.

1302Steve


duncombemu - September 20th, 2003 at 10:44 PM

This engine was running perfectly before I replaced the crank shaft seal. No seizing, knocking or strange noises.
1302Steve, what would the signs be when engine is running, that the 'rear main bearing may be flogged out'?
If this is so, then what has to be done?
Mark


Dasdubber - September 21st, 2003 at 07:18 PM

This may not be the cause of your headaches but I had exactly the same problem once whereby it wouldn't turn over once I torqued up the gland nut (on my 40hp engine) after replacing the crank seal.

Turns out that when I put the flywheel on, I must have accidentally flicked the spring (that sits inside the seal to keep it tight on the flywheel) off and it jammed between flywheel and shims. Ended up needing a new seal and a couple new (second hand) shims but after that, no probs at all.

Maybe just rule out this possibility before doing a tear down!
Alan


1303Steve - September 21st, 2003 at 09:42 PM

Hi

Sometimes when you pull a motor down you wonder how it kept running, soemtimes you will get a vibration in the gearstick, oil leaks or bad oil pressure when the bearings & case are flogged out.

To see if the bearing is moving back & forth in case, with flywheel off, give the bearing a tap with a block of wood & a hammer, put dial indicator on the bearing thrust face, then give crank pulley nut a tap with the hammer, there should be no movement. The cure, rebuild the motor.

1302Steve


vw54 - September 21st, 2003 at 10:12 PM

The best method ive found for doing the end float, all things being equal is to fit
the flywheel without any shims or oil seal first.

do up the flywheel nut firm and make sure you still have movement in the crank back and forwards and rotataional as well.

The torue up the nut and check rotation again both back and forward.

Measure the distance the fly wheel mooves minus the 0.003" for the freeplay and thats the total thickness of the shims required.

Remove the fly wheel and fit the shims only and retighten the fly wheel back onto the engine and torque again and re check the movement, to be certain.

Refit again with the oil seal and you shouldnt have any problems,


breville - September 30th, 2003 at 06:01 PM

might sound silly but where did you put the o - ring

did you put it over the flange where the four dowels are up against the shims (like dopey me)
or did you put it in the right place - inside the flywheel flange on the flywheel where the old one may still be.

regards.
:jesus

[Edited on 30-9-2003 by breville]


duncombemu - October 1st, 2003 at 02:05 PM

I just had too many shims. One was so consealed at the back
that I didn't see it and put all the shims back and extra ones
and it all came to a 'serious halt'.
Yes, it doesn't take much to muck everything up.

Regards,
Mark:thumb


Baja Wes - October 1st, 2003 at 02:24 PM

so if the flywheel was hard up against the shims, how were you getting end float still?

This is what Steve is talking about, it sounds like your rear main bearing is moving in the case. The flywheel will clamp the end shims hard against the rear main bearing. So the only thing left to give you end float is the rear main bearing moving in the case.