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Wed Sep 26, 2007 8:13 pm

The dowel for the front bearing (thrust) is loose side to side. Is their a way to repair this? I keep thinking I have heard about over sized dowels. Also this is a std line bore.

Wed Sep 26, 2007 9:19 pm

Do you mean the dowel is loose in its' hole in the bearing saddle, or do you mean the dowel is tight and the hole in the bearing itself is loose where it sits over the dowel?

Wed Sep 26, 2007 9:53 pm

I think he means loose in the case half??

IF that is the case either over size.....OR Clean the area very well and use a threadlock and sealer (John Deere is my brand)......Tap it a little to make sure it seats.

Thu Sep 27, 2007 7:32 am

Redrill the dowel hole in the case to a different location.
The bearing doesn't care how it is oriented in the case.
Unless you have a main bearing w/o the oil groove on the backside to feed the crank and the oil ports have to match, it won't hurt a thing.

Thu Sep 27, 2007 10:19 am

Leave it alone. The dowel is NOT there to do any work. It is there for locating the bearing.

The mains should have the bearing crush to hold the bearings in place. That is all.

Thu Sep 27, 2007 11:45 am

nsracing wrote: Leave it alone. The dowel is NOT there to do any work. It is there for locating the bearing.

The mains should have the bearing crush to hold the bearings in place. That is all.

That is 100% correct.

Thu Sep 27, 2007 12:20 pm

nsracing wrote: Leave it alone. The dowel is NOT there to do any work. It is there for locating the bearing.

The mains should have the bearing crush to hold the bearings in place. That is all.

So why is there a dowel hole at all then?
Other than orienting # 4 you don't need any dowel pin holes then?
When the crush is lost, and it will be eventually, the dowel needs to be there, and not loose in the case.

Thu Sep 27, 2007 1:24 pm

I had the same problem a while back. I solved it by taking a drill bit slightly larger than the side to side hole and drilling the original hole out in both the case and bearing. Then I cut the drill bit to the same length as the original pin and used that as the new pin. Perfect fit and never caused any problems.

Thu Sep 27, 2007 1:24 pm

The dowel will not hold on to a free-floating bearing. There is probably LESS damage without the dowel pin there when the bearing does come loose.

I am sure you have laid eyes on a dowel pin that did its number on the mains when THERE WAS NO BEARING CRUSH. :D

The dowels are there to locate the oil holes. Now since the grooves on a lot of the Mahles are on the backside, it does not matter if there is dowel or not. But on German Kolbenshmidths bearings, you gotta have the dowel hole location since the grooves are on the inside.

A proper "bearing crush" is needed to secure the bearing without binding the journals. Hence, it (alignbore) is a job best left to experts. A lot of people take the alignbore jobs for granted. This is one machine work that has to be perfect...PERFECT! Yet people are happy just to see a bright finish or some kind of hole in the mains.

Thu Sep 27, 2007 3:06 pm

I think every used case I have ever put together the dowel pins are a little sloppy. Never had a problem.

I'd listen to nsracing, he knows his stuff.

Thu Sep 27, 2007 3:24 pm

OK Nick.
VW put the dowel pin holes there for a reason and they were never loose on the case half.
I understand what you are saying and agree for the most part but I always repair the loose dowel holes.......fair enough?

Michael Fischer wrote: I think every used case I have ever put together the dowel pins are a little sloppy. Never had a problem.

I'd listen to nsracing, he knows his stuff.

Quit swinging on Nick's bag sack......... :roll:
You have enough problems:
http://www.thesamba.com/vw/forum/viewtopic.php?t=255468

Thu Sep 27, 2007 3:37 pm

So Nick, does that mean you leave the dowel pins OUT when you build engine's? :P :lol: :wink:

Thu Sep 27, 2007 4:56 pm

Thanks, I like the idea w/the drill bit and fully trust NSR as he did the machine work on my 1776.

Thu Sep 27, 2007 5:05 pm

Funny story, we went to moab last weekend drove the rail around all saturday. It loved the sand, then woke up sunday morning and it had rained all night, I looked out side to see water running about 3 feet deep, needless to say the sand rail does not float. So I didn't even try to start it I probably got 1 1/2 gallons of water/sand out of the carbs,exh, and engine oil. So this is why I am tearing it down I am pretty suprized this is all I found w/a GEX

Fri Sep 28, 2007 2:34 am

tasha201984 wrote: I am pretty suprized this is all I found w/a GEX

You mean they actually built one that didn't blow? :shock:
Must've been built on a Tuesday.

Fri Sep 28, 2007 5:34 am

keifernet wrote: So Nick, does that mean you leave the dowel pins OUT when you build engine's? :P :lol: :wink:

I leave them in there because the "hairsplitters" will be looking for them things. :lol:

Some of the Wasser cases have the #1 bearings without the dowel. Although they did have tiny tangs. So there.

I just need one dowel for the #4 bearing. Might be a good myth-buster...

Fri Sep 28, 2007 6:26 am

nsracing said,
I just need one dowel for the #4 bearing. Might be a good myth-buster...

The problem with this is # 2 & 3 bearing can possibly move fore or aft causing issues with interference or optimum oil flow.