Main and Rod Bearings

[Riverfurm]

The machine shop supplied me with bearings and gaskets from Top Line when I picked up my block and crank. I know I got the wrong rod bearings and thought the main bearing where packaged wrong due to the fact I got six bearings with groves and oil holes and four with no oil holes or groves (cap bearings). So I contacted Top Line and this is the Email I got......

the bearing factory use to place a note in the MB box a long time ago and they have stop doing that. basically the fully grooved #4 main is from the forklift application. instead of the factory carrying two part numbers they made one set to fit both automotive and industrial. there will be no problem using the #4 fully grooved main bearing.
 
after i sent the mail to you i called the bearing factory and requested the distance of the tang from the edge and width of the tang.
tang from the edge is listed as 2mm and the width of the tang is 3.8mm for the RB056.
 
the RB056 is for the 1.6l gas applications (small rod journals) and the RB068 are for the 1.6l diesel applications (large rod journals).
 
do you need any more information?
 

Has anyone used this set up on their #4 main bearing?

[Vincent Waldon]

I've never heard of a "forklift" connection, but using the fully-grooved halves on #4 is standard rebuild procedure as far as I know, since the #4 crank drilling feeds the rod bearings oil supply.

[Riverfurm]

I did not know that :roll:  I had two other engines in the shop and neither had that setup on #4. A 1.6 VW diesel in a forklift, thats a new one two :shock:

[fatmobile]

All the main bearings supply oil to the rods.
 #5 main supplies oil to the 4th rod.
 #4 main supplies oil to #3 rod....
...
 The only main that doesn't supply oil to a rod is #1.

[Vincent Waldon]

Lemme pull my MK2 Bentley when I get home... they have the specific recommendation for #4 but I can't recall the exact wording.

[Riverfurm]

Don't bother. The engine was put together and ran good, no bottom end problems. I sold the car, and few months later it got wrecked.

[fatmobile]

 It would still be nice to know why the grooved bearing is supposed to go in #4 cap,
 because the reasons given here and in the FAQs don't make sense.

I posted this in the other post I bumped.
 I took a look at my MK2 Bentley,
'85 to '92.
 Figure 7.1 shows the same lubrication flow diagram as the Rabbit Bentley.
 intermediate shaft and head have their own supply routes.
 I can't imagine them taking oil from the block, then sending it through the crank before it goes to the head, like the FAQs suggest.

Now, I just got an '85, '86 GTI, Golf, and Jetta,
 "Official Factory Repair Manual" and on pages 13.2 and 13.3 they have the diagram that was squeezed onto page 39 of the MK2 "Service Manual",..
 the blown up picture of the block/crank/bearings. (actually looks like they put the same picture on the next 2 pages also, ha)

Instead of saying:
 "lower main bearing"
 "shell (#'s 1,2,4,5)"
 Like the MK2 "service manual".

 In the same place; the "Official Factory Repair Manual" says:
   Bearing shell 1,2,4 and 5
  for cap 1, 2 and 5 without
  oil groove
  cover 4 with oil groove
 do not interchange worn bearing shells (doh)

I'm still not sure why #4 is special,
  all the mains supply 1 rod except #1.