Lister Engine Forum

Lister Engines => Original Lister Cs Engines => Topic started by: ajrolfe on June 27, 2019, 11:39:29 PM

Title: CS6 loose flywheel
Post by: ajrolfe on June 27, 2019, 11:39:29 PM
Hi, I wonder if anyone has a solution to my problem
Startomatic with the heavier flywheels and the one with 2 grooves to run generator has a problem.
The shaft is 50.4--to 50.8 in diameter, but the hole in the flywheel is bigger. Previous owner had 'solved' this by putting 2 hacksaw blades ontop of one another in the keyway and then hammering {with a lot of misses} the key home. True the flywheel no longer wobbled, but as it was now off centre the result was a CS 6 trying to walk out the door. Quite unnerving.
I can get it bored, sleeved and a new keyway spark eroded but its a tad expensive at 5-600.
i also need a 3kw generator to go with it.
Or maybe it would be easier to buy a Startomatic and sell this engine.

Any thoughts?
Title: Re: CS6 loose flywheel
Post by: ajaffa1 on June 28, 2019, 12:50:11 AM
Hi Ajrolfe, it kind of depends on where you live. Here in Australia I would pay a visit to Rob at Old timer engines and pick up a second hand replacement for about $50. In the USA you should probably contact Gary at Diesel Electric Services, he might be able to point you to a replacement, he would certainly be able to provide a suitable generator head and any other spares you need.

New flywheels can be purchased from DEV Precision in India but I suspect the delivery costs might be exorbitant and the quality questionable.

Bob
Title: Re: CS6 loose flywheel
Post by: BruceM on June 28, 2019, 01:43:05 AM
I don't think anyone in Rajkot or India is casting SOM flywheels.

I would study the oversized hole problem carefully.  How true is it? Steel or brass shim stock of any thickness is available, if you can get a decent fit with a hand cut and fitted sleeve, I'd think about Weldbonding the sleeve in the wheel.  I'd do the fitting first with a piece of 2" shaft- I got one pretty cheap on Amazon and use it for flywheel balancing per 38ac's method.  Check flywheel runout on the crankshaft with the shim stock before Weldbonding it to the wheel alone.  Likewise I would think about brazing the hole, and hand fitting and rebrazing to get rid of runout, both lateral and vertical.

Lots of work and way easier to grab a replacement if available. 

Best Wishes,
Bruce
Title: Re: CS6 loose flywheel
Post by: 38ac on June 28, 2019, 03:00:58 AM
Unfortunately to my knowledge there is no cheap and easy workaround for a worn flywheel bore. The heavy flywheels are much worse with this issue than the light ones.  The Amish fixed them by installing a taoer lock or QD bushing which requires a trip to a well equipped machine shop.
Title: Re: CS6 loose flywheel
Post by: Jordan on June 28, 2019, 04:18:49 AM
i also need a 3kw generator to go with it.

I thought so too, until someone pointed out that I could use a larger output generator (which might be easier to find).
It will produce as much kW as the engine can cope with supplying, then no more.
I hope that's right, because I got an 8 HP alternator.
Title: Re: CS6 loose flywheel
Post by: mikenash on June 28, 2019, 06:43:51 AM
Unfortunately to my knowledge there is no cheap and easy workaround for a worn flywheel bore. The heavy flywheels are much worse with this issue than the light ones.  The Amish fixed them by installing a taoer lock or QD bushing which requires a trip to a well equipped machine shop.

+1 on taper lock
Title: Re: CS6 loose flywheel
Post by: ajaffa1 on June 28, 2019, 08:15:10 AM
DEV Precision quote part numbers for Lister/Listeroid flywheels here: http://lister-petter.devprecisionengineers.com/otherdetails/Lister_plates_part_number.pdf

Please see plate 5

Bob
Title: Re: CS6 loose flywheel
Post by: BruceM on June 28, 2019, 02:50:11 PM
Thanks Bob, they do seem to list a 25 inch flywheel that could be an SOM type.  Neither US importer Breckenridge or Montieth could get them 12 years ago.
Title: Re: CS6 loose flywheel
Post by: listard-jp2 on June 28, 2019, 02:55:43 PM
The heavy flywheels are much worse with this issue than the light ones.  The Amish fixed them by installing a taper lock or QD bushing.


In your opinion, what is the longevity of a repair like this? as my only concern would be the amount of material requiring removal from the flywheel boss (bearing in mind the flywheel hub is 4" diameter and the shaft is 2" diameter, you only have 1" of material to start with), added to which the reduced section on the flywheel boss would need to be tapped for the QD bush retaining bolts.

Apart from the above I would think it would be far superior to the gib head key method of attaching the flywheel to the crankshaft, as the contact area would be far greater
Title: Re: CS6 loose flywheel
Post by: 38ac on June 29, 2019, 12:02:57 AM
The ones I have seen locally used a QD bushing type SD. The large end of the taper for that bushing is 2.187 thus not nearly as much material must be removed as compared to a standard taperlock.  So far as. I know it was very successful, quite a few around done that way
Title: Re: CS6 loose flywheel
Post by: BruceM on June 29, 2019, 12:16:31 AM
Butch, do a theory why more SOM flywheel bores worn out?  Seems like with properly fitted key it shouldn't happen (?)  The QD type SD bush sounds like a good solution. 
Title: Re: CS6 loose flywheel
Post by: Jordan on June 29, 2019, 05:39:19 AM
I'd love to see a photo of the machining of a flywheel for a Taper-Loc bush.
Must be done in quite a large lathe?

Title: Re: CS6 loose flywheel
Post by: ajaffa1 on June 29, 2019, 10:38:14 AM
Here is an idea, how about drilling and tapping three holes in the boss of the flywheel. One needs to be directly opposite the key way, the other two need to be 120 degrees in each direction from the first hole. Now fit the flywheel to the crankshaft and use bolts or grub screws to center it using a dial test indicator. Once you are happy with the positioning drive in your gib key and check the concentricity has not changed. Once you are happy that things are how you want them flood the joint with Loctite permanent thread locker.

You will never be able to get it off again unless you heat it to the point where the Locktite softens but all told you should be able to perform this type of repair with an electric drill and a suitable tap for under $30.

Bob
Title: Re: CS6 loose flywheel
Post by: 38ac on June 30, 2019, 12:00:43 AM
Next time I see a modified hub I will snap a few photos. 
If one thinks for a while about why there are flywheels  on the crankshaft it will come to light why the heavier they are the more force that is transmitted to the shaft via the key. This is also the reason why Lister used a heavy duty bi-metal bearing shell  on the upper end of the connecting rod for the heavy flywheel 6/1 engines.
Title: Re: CS6 loose flywheel
Post by: BruceM on June 30, 2019, 02:06:20 AM
Thanks 38AC.  I can understand higher peak forces on on crank and everything attached due to the higher rotating mass of the SOM wheels.  They are so massive that the power pulse is like hitting a huge chuck of cast iron with a sledge hammer.

Uh oh, a different upper connecting rod and bearing on SOM's????  On the Listeroids, it's just a bronze bushing.  What will happen to that if I get my SOM type flywheels mounted?



Title: Re: CS6 loose flywheel
Post by: 38ac on June 30, 2019, 02:16:26 AM
Bruce, at some point, maybe from day one? Lister changed to a bronze backed shell for the heavy flywheel 6/1 and all 8/1 engines. I have read differing accounts of upper only, or both and when it was implemented Kevin is as knowledgeable as anyone about them maybe he will chime in.
I wouldn't loose any sleep over having the softer shells in your engine. However you might want to have a set on hand just in case.
Title: Re: CS6 loose flywheel
Post by: BruceM on June 30, 2019, 02:22:28 AM
Thanks, 38ac, much appreciated. I keep stalling the heavy flywheel project as lifting them onto the crank in my small engine room is a bear, and I've already had my left leg bit by a falling flywheel.
Title: Re: CS6 loose flywheel
Post by: listard-jp2 on June 30, 2019, 09:17:52 AM
The ones I have seen locally used a QD bushing type SD. The large end of the taper for that bushing is 2.187 thus not nearly as much material must be removed as compared to a standard taperlock.  So far as. I know it was very successful.

Would you please have a part number for that item, and a link to a supplier

Here is another thought to consider. What if a metric version of this item QD bushing (50 mm I/D) was used? This would then allow a  damaged crankshaft to also be reclaimed at the same time (a minor benefit would also be that the subsequent machining of the crankshaft would remove any light rust pitting and give it an as new appearance on the exposed surfaces). Granted a modified starting handle would also be needed, to suit the now 50 mm diameter shaft

Then taking it a step further, the above modification would also then allow under-size regrinds on the main bearing journals, granted replacement sealing rings would also be required.

This would allow the original crankshaft to be retained :)
Title: Re: CS6 loose flywheel
Post by: ajaffa1 on June 30, 2019, 09:58:55 AM
Hi listard-jp2, it would be perfectly possible to regrind the crankshaft and fit metric taper lock bushes, the problem is that the main crankshaft bushes only come in one size. This leaves you with only two choices 1. find a metric taper bearing that will fit or 2. learn Babbitt casting and make your own undersized bushes.

Another possibility would be to only grind the shaft exposed outside of the crankcase leaving the existing bearing surface as it is. I guess it depends how much wear there is in the main crank journals.

Bob