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Author Topic: Six grooved main bearings and Four smooth  (Read 2620 times)

June 28, 2008, 06:45:57 pm

skifree

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Six grooved main bearings and Four smooth
« on: June 28, 2008, 06:45:57 pm »
Went to put the crank in my 1.6td opened the new sealed mahle original box and there were Six grooved and four smooth main bearings.Is this a packaging mistake?



Reply #1June 28, 2008, 07:00:49 pm

Vincent Waldon

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Six grooved main bearings and Four smooth
« Reply #1 on: June 28, 2008, 07:00:49 pm »
Bearing saddle #4 takes slotted ones on both sides... you'll likely  see it when you pull the old ones as well.
Vince

Edmonton, Alberta, Canada
2001 silver TDI Jetta Malone Stage 1.5 , 2001 blue TDI Jetta SBIII 216s Malone Stage 3, 1970 Bay Window bus

Gone but not forgotten: 1969/1971 Beetles, 1969/1974 Westies, 1979 Rabbit, 1986 TD Jetta, 1992 gas Jetta, 1994 TD Jetta

Reply #2January 26, 2010, 04:49:51 pm

fatmobile

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Re: Six grooved main bearings and Four smooth
« Reply #2 on: January 26, 2010, 04:49:51 pm »
I'm doing a block and am wondering:,...
 why number 4?
 I was reading the FAQs and someone said it supplies oil to the head and one of the rods,..
 but looking at the Bentley it shows oil to the head has it's own route. (Rabbit Bentley '77-'84)

 All the mains supply one rod bearing,..
 except #1 (5 mains, 4 rods).
So I'm thinking put it on #1.
Tornado red, '91 Golf 4 door,
with a re-ringed, '84 quantum, turbo diesel, MD block

Reply #3January 26, 2010, 06:45:21 pm

jack's lack

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Re: Six grooved main bearings and Four smooth
« Reply #3 on: January 26, 2010, 06:45:21 pm »
from figure 16 pg 13-10 of the MKIII Bentley

Main Bearing Shells
without groove: for main bearing caps no. 1, 2 and 5
with oil groove: for cylinder block and main bearing cap 4

The Bentley does have a parenthetical caveat that says (except diesel)
I am running mine on no. 4 and the old bearings I took out were 360º on number 4, and I am assuming that was factory.
1982 Rabbit diesel L 4 door
AAZ, K14, Giles pump, PD150 intake, P&P'd head, ceramic coated pistons, 2.5" stainless down pipe & exhaust. FK coils

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Reply #4January 26, 2010, 06:58:22 pm

fatmobile

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Re: Six grooved main bearings and Four smooth
« Reply #4 on: January 26, 2010, 06:58:22 pm »
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.   
Tornado red, '91 Golf 4 door,
with a re-ringed, '84 quantum, turbo diesel, MD block

 

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