SiV6Qcoupe

Hi

I will be measuring my crank bearing clearances this weekend and if any of you Workshop manual owning people are willing to share a little info I would like to know the max. allowable clearances on the rod bearings and main bearings and what max. endplay there should be on the crank.

According to my Haynes manual main bearing caps should be torqued to 48Ibf ft(65Nm) and the big-end bolt to 22Ibf ft(30Nm) + 1/4 turn, can anyone verify if this applies to the V6?

Many thanks

MikTip

axial clearance-

Install dial indicator with holder VW 387 on oil pump and set indicator against crankshaft counterweight.
- Push crankshaft (longitudinally) toward dial indicator by hand.
- Set dial gauge to zero.
- Push crankshaft away from dial indicator and read gauge.
Specifications:
New: 0.07-0.23 mm (0.0027-0.0091 in.)
Wear limit: 0.25 mm (0.0098 in.)

Checking radial clearance

Note: Radial clearance is measured using Plastigage.

Plastigage Type Color Measuring range

PG-1
Green
0.025 - 0.076 mm

PR-1
Red
0.050 - 0.150 mm

Remove crankshaft bearing cap.

- Clean bearing shell and crankshaft journal.

- Place Plastigage on crankshaft journal over entire width of bearing, or in bearing shell (arrow).
- Install crankshaft bearing cap with bearing shell and new bolts.
- Tighten to 60 Nm (44 ft lb) plus1/2-turn (180).

CAUTION!

DO NOT turn the crankshaft or allow it to rotate during the measurement with Plastigage in place.

Remove crankshaft bearing cap again.

- Determine width of Plastigage and corresponding thickness using measuring scale provided.

Specifications:
New: 0.018-0.045 mm (0.0007-0.0018 in.)
Wear limit: 0.10 mm (0.0039 in.)

Crankshaft dimensions

Reconditioning dimension
Crankshaft journal diameter mm - (in.)
Connecting rod journal diameter mm - (in.)

maximum size (from nominal) -0.022 (0.00087) -0.022 (0.00087)
Basic dimension (nominal)
65.00 (2.559)
54.00 (2.126)

minimum size (from nominal) -0.042 (0.00165) -0.042 (0.00165)
maximum size (from nominal) -0.022 (0.00087) -0.022 (0.00087)
1st undersize (nominal)
64.75 (2.549)
53.75 (2.116)

minimum size (from nominal) -0.042 (0.00165) -0.042 (0.00165)
maximum size (from nominal) -0.022 (0.00087) -0.022 (0.00087)
2nd undersize (nominal)
64.50 (2.539)
53.50 (2.106)

minimum size (from nominal) -0.042 (0.00165) -0.042 (0.00165)
maximum size (from nominal) -0.022 (0.00087) -0.022 (0.00087)
3rd undersize (nominal)
64.25 (2.530)
53.25 (2.096)

minimum size (from nominal) -0.042 (0.00165) -0.042 (0.00165)


Connecting rod bearing clearance, checking

Replace connecting rods only as complete sets.

Do not interchange connecting rod bearings shells.

Always replace connecting rod bearing cap bolts.

Checking radial clearance

CAUTION!

Bearing shells must be reinstalled in their original location and orientation. Always label the bearing shells according to their installed position before removing. NEVER interchange used bearing shells.

- Mark connecting rod and bearing cap with light punch marks (arrow) before removing.
- Remove connecting rod bearing caps.
- Clean bearing caps and journals.
- Place Plastigage over entire width of bearing journal or in bearing shell.

Re-install connecting rod bearing cap.

- Tighten bolts to 20 Nm (15 ft lb) only; do NOT tighten further.

CAUTION!

DO NOT turn the crankshaft or allow it to rotate during the measurement with Plastigage® in place.

- Remove connecting rod bearing caps again.

- Determine width of Plastigage® and corresponding thickness using measuring scale provided.

Specifications:

New: 0.015 to 0.062 mm (0.0006 to 0.0024 in.)

Wear limit: 0.12 mm (0.0047 in.)

Thats about all I can remember........;O)

SiV6Qcoupe

Thanks ...great memory! ... ;-)

Gear2113

this newbie just wanted to make sure that the oil hole on the bearing goes on the side of the rod or on the cap? Thanks in advance for anyone that can help me verify this.

Rusty Spokes

I don't think it matters.. Oil pressure feed through the crank to the rods....a hole in the rod bearing shell should not matter when the engine is running, unless you have oil quirters built into the rods. What engine are we talking about?

Gear2113

​​​​​ Sorry what I have is a 2001 Audi Avant with 1.8T manual. It has oil squirters at the bottom of the cylinders. Well thank you for your response. Was unsure since the rod and cap both have oil holes.