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8 Dowelling a crank..
Ian Bugden - January 29th, 2007 at 06:31 PM

Hi all,
If you have a engine that is complete is it possible to 8 dowell the crank still in the case?? the flywheel is a no brainer

Thanks in advance.

Ian.


jnr356 - January 29th, 2007 at 06:51 PM

yes ,i did mine (my old man had a jig)


vw54 - January 30th, 2007 at 06:08 AM

It would be easier to do out of the engine

But why both fitting 8 dowels if the rest of the engine is old ??


VWCOOL - January 30th, 2007 at 07:43 AM

I don't think eight dowels with a jig would be too effective...


jnr356 - January 31st, 2007 at 07:28 PM

Quote:
Originally posted by VWCOOL
I don't think eight dowels with a jig would be too effective...


been in for 8 years & over 80,000k's
and copped a thrashing

pretty effective i'd say


VWCOOL - January 31st, 2007 at 08:33 PM

I have four dowell cranks like that... ;)


jnr356 - January 31st, 2007 at 09:50 PM

my hero


dangerous - February 1st, 2007 at 06:33 AM

I have done a couple of 8 dowel jobs on assembled engines, but it can be a pain.

The stock pulley can wobble a bit when it is supported on it, as you drill and ream the holes.

If the reason is to add 4 because the original 4 are damaged?,
then there will be raised burrs(Raymond's), which can not be effectively removed,
without total disassembly.

Once the FW is done, you can drill and ream through the FW.


Ian Bugden - February 1st, 2007 at 03:25 PM

The reason I am contemplating this is I am looking at getting one of those zero mile new brazilian 1600's and as I am lightening the flywheel I thought I may as well add some more dowells. This means the crank is staying in the case.

Ian.


Craig Torrens - February 1st, 2007 at 04:26 PM

why lighten the flywheel on a 1600 with a standard cam?


VWCOOL - February 1st, 2007 at 08:13 PM

sure, try it, but you'll most likely find that a standard engine relies a lot on its flywheel for smoothness, an unbalanced crank (are these late-model cranks cast iron?) won't be happy being revved very fast, the standard cam won't let it anyway, the OE assembly probably won't last very long if you do and that 8-dowells - even dodgy hand-drilled ones! - are superfluous/useless on a 60-horse engine.


Ian Bugden - February 3rd, 2007 at 09:52 AM

I tend to agree with the 8 dowell being overkill. However lightening the flywheel does not make the engine rev higher only a little quicker. the plan for down the track is to install ratio rockers and I will be running dual carbs with a free flowing exhaust. This should give a few extra ponies without over stressing the engine.

Ian.


Gracey - February 3rd, 2007 at 11:32 AM

I ran an 1835 with a 12lb flywheel 48IDA's etc. for years with only 4 dowels and I never had a problem with it.
Personally I would never run a lightened flywheel on a stock motor, especially a Brazilian motor.
The only time it will rev quicker is when it's in neutral. Not trying to be a smartarse, just trying to help.

Andrew


Judsons4eva - February 3rd, 2007 at 12:32 PM

In my opinion there is no need to 8 dowell a crank unless the 4 stock dowells are crook. With 370 ftlb of tightening torque the engineering theory is that flywheel is held firm by the contact between the flywheel and crank flat sections and the dowells are only a locating and precautionary measure if the bolt lossens. My experience says tighten the flywheel correctly, use some low strength loctite (screw lock - otherwise you'll never undo it) and you should have no problem.

Ken


BeetleJuice - February 6th, 2007 at 06:38 AM

Sorry to highjack this thread, but Ken you have a nice collection of cars.

Could you or have you ever posted pics of them on this site?

Would like a look at the judson engine & the Porsche!

[ Edited on 5-2-2007 by BeetleJuice ]


Judsons4eva - February 6th, 2007 at 08:36 AM

Quote:
Originally posted by BeetleJuice
Sorry to highjack this thread, but Ken you have a nice collection of cars.

Could you or have you ever posted pics of them on this site?

Would like a look at the judson engine & the Porsche!



Thanks -
Spyder Pics

http://s24.photobucket.com/albums/c47/Judsons4eva/spyder/ 

Oval - http://www.fastlane.com.au/Custom_Shed/VW_1956.htm 

OR

http://s24.photobucket.com/albums/c47/Judsons4eva/oval/ 


[ Edited on 6-2-2007 by Judsons4eva ]


Judsons4eva - February 6th, 2007 at 10:40 PM

One more pic of Judson
http://vwjudsonregister.tripod.com/ken_johnsens_page.htm 


BeetleJuice - February 7th, 2007 at 06:03 AM

Thanks Ken

Great cars!


shaihulud - February 7th, 2007 at 04:08 PM

Be extremely careful when 8 dowelling a crank.

In the 1980s I watched an inquest in Canberra into the death of John Egan the famous engine builder.

As well as a whole series of errors that were in some cases based on familiarity breeding contempt and after the Scat engine was sectioned into about a dozen slices it was acertained that two of the 4 new pins that were put into the crank when it was 8 pinned were longer than the others. The inner face of where the crank is attached to the flywheel had been machined down too much, two of the pins protruded and so the big nut was tensioned down onto the ends of the pins, not the outer face of the flywheel. When they checked for end float of the crank by measuring at the outer edge of the flywheel, that they were really measuring fly wheel rocking.

During a tragi-comedy of errors, the engine got out of control, flew off its inadequate mountings and the shaft that connected the engine to the dynamometer hit John Egan who was breaking the basic rule of all engine testing, never be in the dyno room when the engine is running, and it killed him.

I'm not saying that that will happen to you, but it did happen to John Egan, the head of the TAFE engineering section whose dyno they were using, the owner of one of Canberra's best known suspension companies who was a well known car racer and one of their mates.

The coroner was scathing in his criticism of them all, Egan included except for the mate, who being an amateur was allowed to know less than the professionals and therefore to make mistakes.

So, I repeat. Be careful.


Judsons4eva - February 7th, 2007 at 08:18 PM

SCAT - say no more!


shaihulud - February 7th, 2007 at 11:33 PM

Yeah. Believe you me. Seeing the pieces of a Scat engine that had been sliced up like a loaf of bread was something worth seeing. The forensic engineer who did it was really annoyed that he had to do it to a Scat engine to find out what was wrong with it.