Flywheel Removal ? Tips?

[bnk999]

1974 75hp chrysler 757ha <br /><br />Ok so I am pretty far into replacing my powerhead, got the new (used) powerhead on the motor leg and almost everything on but now I have to put on the distibutor belt so I have to pull the flywheel -- <br /><br />What is a good way to get the nut off the flywheel<br />All my chrysler manual says is remove nut securing flywheel to crank-- First of all is this nut reverse threaded or regular? and second how can I stop the motor from spinning when I'm wrenching on the nut?

 

[Scaaty]

Re: Flywheel Removal ? Tips?

Impact wrench run by an air compressor, or an electric which you might be a able to rent. Pretty sure standard right hand thread

 

[scotiany]

Re: Flywheel Removal ? Tips?

Nut is removed by turning wrench/socket ccw. If using a flywheel puller, make sure it's a bolt on type and not one that contacts the flywheel teeth. Otherwise, you'll be buying a new flywheel. What about putting it in reverse and giving wrench a sharp blow with a hammer to get nut off.

 

[scottscale]

Re: Flywheel Removal ? Tips?

i managed to remove my flywheel in about 10 minutes over the weekend:<br />i did not have access to an air compressor so i wraped a small section of chain around the flywheel hooking onto the two "pull-start" dogs and then passed the loose end under the starter motor before running a bolt through the two chain ends to form a figure of 8.<br />the wheel brace from my truck took the nut right off (right hand thread) without the need for a 4ft bar or serious grunt work. if you do this please be careful - there is no need to be rough on the flywheel as you may damage the engine anciliaries with the chain.<br />once the flywheek is off use a proper set of gear pullers to load up the flywheel against the crankshaft. then give the flywheel a couple of slaps with a rubber mallet around the circumference and the flywheel should pop right off.<br />if this does not pop the unit off in under 15 minutes then you may need to try using some heat to expand the flywheel from the taper. - i left the motor cover off so the 100DegF texas sun would get the flywheel hot prior to starting the job. oh, WD-40 is also a good idea. let it soak in overnight if pos.<br />good luck<br />es

 

[bnk999]

Re: Flywheel Removal ? Tips?

Awesome! Thanks alot for the tips guys-- will work on this tonite and let y'all know--

 

[novicetech]

Re: Flywheel Removal ? Tips?

I used a harmonic balancer removal tool on my 70 hp which is about the same as yours. Tighten a little whack it with hammer over and over. Make sure you leave the nut on the crank shaft a few turns these can be violent when they break loose, you will think it broke. You can put a large screw driver through the lifting eye and into the gear valleys on the flywheel to keep it from moving. Also make sure you follow the directions for lapping the flywheel before you try to put it on.

 

[bnk999]

Re: Flywheel Removal ? Tips?

Got it off last nite -- air compressor with impact wrench is definitly the way to go on that flywheel nut-- When I tried with a regular wrench, the flywheel would spin-- with that impact wrench it didn't even move the flywheel, then I used a puller with a prybar under the flywheel applying pressure and hit the top of the puller with a hammer -- voila- it came off <br />\<br />--Thanks for all the advice --

 

[Albatross]

Re: Flywheel Removal ? Tips?

Originally posted by novicetech:<br /> I used a harmonic balancer removal tool on my 70 hp which is about the same as yours. Tighten a little whack it with hammer over and over. Make sure you leave the nut on the crank shaft a few turns these can be violent when they break loose, you will think it broke. You can put a large screw driver through the lifting eye and into the gear valleys on the flywheel to keep it from moving. Also make sure you follow the directions for lapping the flywheel before you try to put it on.

 

[Albatross]

Re: Flywheel Removal ? Tips?

I was all excited and ready to have a go at removing the flywheel on my 1978 Chrysler 75HP (stator is stuffed) when you mentioned lapping the flywheel before replacement. Can you explain what you mean to a bloke working without a manual.<br /><br />By the way, in Australia Chrysler motors are pretty rare these days (most of them rusted to bits years ago) and most mechanics refuse to work on them. But mine is gong strong and pushes my dive boat pretty well so I will keep using it until it breaks. This site is a great help, so thanks to all of you.

 

[bnk999]

Re: Flywheel Removal ? Tips?

Here is what my chrysler shop manual says about lapping flywheel <br /><br />"inspect tapered bore of flywheel and taper on crankshaft for fretting or working. If there is evidence of this condition or if the motor has 25 or more hours the flywheel must be lapped. <br />1. apply a light coating of a water base valve lapping compund of 240 grit or finer to tapered portion of crankshaft.<br /><br />2 Install flywheel on crankshaft and rotate flywheel gently back and forth about 1/4 turn -- do not spin flywheel completely around crankshaft.<br /><br />3 Rotate flywheel 90 degrees and repeat above operation.<br /><br />4 Remove flywheel, wipe compund off crankshaft and flywheel. Taper in bore of flywheel should have a minimum of 80% surface contact with taper on crankshaft. <br /><br />Hope this helps