International2cvFriends.com
http://www.international2cvfriends.com/forum/

Crankshaft / camshaft
http://www.international2cvfriends.com/forum/viewtopic.php?f=7&t=2380		 Page 1 of 1
Author:  EirikJ [ October 31st, 2010, 12:27 pm ]
Post subject:  Crankshaft / camshaft
Hi

I'm currently dismounting an engine coming from a wreck. I have limited space, so need to throw away stuff that isn't good enough as spare parts.

What I'm looking for to save from this engine is the cylinder heads, crankshaft and camshaft. And some other bits'n pieces.

So, I'm unsure on how to judge the wear on the bearings of the cam- and crankshaft. What do I look for, and how do I measure?
Help much appreciated.
Author:  ken [ November 5th, 2010, 12:47 am ]
Post subject:  Re: Crankshaft / camshaft
EirikJ,
with an A series crankshaft, barring catastrophic failure such as a broken crank, it usually seems to be a con rod bearing which lets go first.

The specified clearance for the con rod bearings is 0.08 to 0.13mm, which basically means that if you can feel any movement the crank is suspect.
Much the same story with the main bearings, specified clearance is 0.07 to 0.14mm.

As regards the camshaft, it's usually wear of the lobes which means that they're not worth sending back into the fray.
More often than not, it's the exhaust lobes which wear first, but if it's OK, label the cam followers to put them back in the same location as they were originally.

If it's a dud, sent it over here, so it can be ground by Kent Cams and go out in a blaze of glory on the race track... :roll:

ken.

EirikJ wrote:
Hi

I'm currently dismounting an engine coming from a wreck. I have limited space, so need to throw away stuff that isn't good enough as spare parts.

What I'm looking for to save from this engine is the cylinder heads, crankshaft and camshaft. And some other bits'n pieces.

So, I'm unsure on how to judge the wear on the bearings of the cam- and crankshaft. What do I look for, and how do I measure?
Help much appreciated.
Author:  Sean [ November 5th, 2010, 9:27 am ]
Post subject:  Re: Crankshaft / camshaft
EirikJ wrote:
Hi

I'm currently dismounting an engine coming from a wreck. I have limited space, so need to throw away stuff that isn't good enough as spare parts.

What I'm looking for to save from this engine is the cylinder heads, crankshaft and camshaft. And some other bits'n pieces.

So, I'm unsure on how to judge the wear on the bearings of the cam- and crankshaft. What do I look for, and how do I measure?
Help much appreciated.


Also have a look under the cover for the oil pump

deep scoring or signs that the rotors have been wiping metal onto the cover indicate that the oil change reigeme hasnt been what it should or that one of the bearings is letting go

keep all the studs and special bolts and nuts
pistons may be worth keeping as long as there isnt scuffs on the skirts

if the oil lines are crispy ill have the hex bits off them ;)

Sean
Author:  EirikJ [ November 5th, 2010, 11:47 pm ]
Post subject:  Re: Crankshaft / camshaft
Thanks guys.

Taking my time and try to make a post that might be useful for someone :)
Took the advice and removed all studs/bolts etc. from the engine casings before I bin them.
The reason I bin the enginecasing is that it doesn't have external oilfilter.(AM2 engine)
Cant see me using this over one that has. Lack of oil-filter probably ruined the crankshaft, long long time ago.

I've just been out measuring the stuff, thought maybe people would like some pictures of it. And correct me if I have misunderstood something regarding checking the components.

I work a lot with engines in my job, so know a lot, but I have never worked on other engines with the type of cam/crank-bearings as on the 2CV.

Very simplified stuff coming. Ask a forum :P or consult the workshop manual for more....

Camshaft:
Visual inspection. The cams are in bad condition. Lot's of stuff can be measured regarding the cams, but if it looks ok, they probably are. Should be smooth without pitting, scratches or blue/brown color. Refer to the workshop manual for more measurments.
Image


Measuring the endfloat. That's what you was talking about Ken? Seems like endfloat is all you can measure(with normal tools), as it seems the 2CV-cam and crank cant have the bearings checked like other normal car-engines. Should be 0,04 - 0,09. This is over 0,1 and therefore fubar?
Image


The "keep the oil inside" turbine thing on the cam. As I understand from other threads, the "black" part(groves) should ideally be wider than the shiny parts(tops). This is therefor quite worn.
Image


Oilpump:
The surfaces should be plane and shiny without scratches. This is in bad condition.
Image Image
Image

Crankshaft:
Measuring endfloat at the main bearing in front. Should be between 0,07 - 0,14 mm. This was ok.
Image


Measuring endfloat at the big end for the conrod. Should be between 0,08 - 0,13. This is ok:
Image

The other big end conrod bearing is not, so crank is busted. (Witch I of course knew, as I took this engine apart long time ago. But I have one more to take apart and check. The reason for the first post in this thread.) Maybe this happened because of the lack of oilfilter:
http://www.youtube.com/watch?v=d88jxJyvHE4



So I wonder, it's not possible(easy with normal tools) to measure radial play in the bearings? Like these ones?
Image Image

Just feel for radial play? There should be none of course.
Especially the conrod. If you cant feel any radial play, it should be ok?
Author:  ken [ November 6th, 2010, 9:54 pm ]
Post subject:  Re: Crankshaft / camshaft
EirikJ,
you're right, I was quoting figures for 'end float'.
Finally found a reference for main bearing diametrical play, should be between 0.055 to 0.111mm.
As you say, somewhat academic when 99 times out of 100, it's a big end which fails first.

Regarding that oil return scroll on the camshaft (behind the points box), unlike the item on a gearbox input shaft, it's most unlikely that you'll find it worn on a camshaft.
Isn't that because there'd have to be so much wear on the front camshaft bearing that the points wouldn't have a hope in hell of working... :lol:

ken
Page 1 of 1 All times are UTC + 1 hour [ DST ]
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
http://www.phpbb.com/