Author Topic: Bearings on crank too big? Crank hard to turn by hand  (Read 5228 times)

January 09, 2011, 07:52:34 pm

kevinm

  • Junior

  • Offline
  • **

  • 78
Bearings on crank too big? Crank hard to turn by hand
« on: January 09, 2011, 07:52:34 pm »
Im installing new standard size Glyco bearings i got from Myke W and am noticing around 40ft lbs. they start to get a little snug.  Around 45ft lbs. the crank still turns by hand but seems like it may only be due to the clevite assembly lube.  Plastigage at 45 lbs shows .001 clearance or maybe a little less on a couple journals which is slightly out of tolerance.  Is this normal and the bearings will open up .0005 or so once running?  Or.....



Reply #1January 09, 2011, 08:02:33 pm

Quantum TD

  • Veteran

  • Offline
  • ***

  • 1195
Re: Bearings on crank too big? Crank hard to turn by hand
« Reply #1 on: January 09, 2011, 08:02:33 pm »
That seems tight. It should spin freely. The only thing I can think of is are you sure you have the bearing caps oriented the right way (i.e. not reversed)?


Reply #2January 09, 2011, 08:08:10 pm

kevinm

  • Junior

  • Offline
  • **

  • 78
Re: Bearings on crank too big? Crank hard to turn by hand
« Reply #2 on: January 09, 2011, 08:08:10 pm »
I checked and there on the right way.  It does spin freely up until the point of say 40ftlbs. then starts to take a little effort to turn... 
Thanks for the input.

Reply #3January 09, 2011, 08:37:36 pm

Vincent Waldon

  • Global Moderator
  • Veteran

  • Offline
  • ***

  • 3255
    • My collection of HOWTOs
Re: Bearings on crank too big? Crank hard to turn by hand
« Reply #3 on: January 09, 2011, 08:37:36 pm »
Are all the bearing caps back with their original mates?  You may already know this... but they are bored as pairs and aren't interchangeable.
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 #4January 09, 2011, 09:21:04 pm

kevinm

  • Junior

  • Offline
  • **

  • 78
Re: Bearings on crank too big? Crank hard to turn by hand
« Reply #4 on: January 09, 2011, 09:21:04 pm »
As in the numbers vw stamped into the cap 1-5? yes.  I hope they were not assembled out of order at vw because i never made a note of how it was when i took the motor apart.

Reply #5January 09, 2011, 09:36:09 pm

Vincent Waldon

  • Global Moderator
  • Veteran

  • Offline
  • ***

  • 3255
    • My collection of HOWTOs
Re: Bearings on crank too big? Crank hard to turn by hand
« Reply #5 on: January 09, 2011, 09:36:09 pm »
Yup... you should be fine then... assuming 1-5 are in the right order.  ;-)

9 times out of 10 when someone finds the crank is tight it's because they didn't know the bearing caps have a specific order... (un)fortunately it sounds like you've got that covered.
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 #6January 09, 2011, 09:37:17 pm

truckinwagen

  • Veteran

  • Offline
  • ***

  • 1895
Re: Bearings on crank too big? Crank hard to turn by hand
« Reply #6 on: January 09, 2011, 09:37:17 pm »
just to check(not that we all dont know already) which end of the motor is number one?
83 Opel Kadett Diesel

Reply #7January 10, 2011, 01:17:12 am

Thezorn

  • Veteran

  • Offline
  • ***

  • 381
Re: Bearings on crank too big? Crank hard to turn by hand
« Reply #7 on: January 10, 2011, 01:17:12 am »
just to check(not that we all dont know already) which end of the motor is number one?

as per bentley, number 1 is the timming end ending with 5 at the clutch end.
Compounded 93 AAZ

Reply #8January 10, 2011, 08:19:00 am

R.O.R-2.0

  • Veteran

  • Offline
  • ***

  • 7335
  • Personal Text
    Pacific Northwest - Oregon - USA
Re: Bearings on crank too big? Crank hard to turn by hand
« Reply #8 on: January 10, 2011, 08:19:00 am »
my grandpa had a block like this. the block was no longer straight, and needed a line bore..
92 Jetta GLI - Black, 1.6D w/ GT2056V turbo..
86 GTI - 4 Door, Med Twilight Gray, Tow Machine..
86 Audi Coupe GT - Tornado Red, All Stock.. WRECKED.
89 Toyota 4Runner - Dark Grey Metallic, LIFTED!

Turbo: exhaust gasses go into the turbocharger and spin it, witchcraft happens and you go faster.

Reply #9January 10, 2011, 12:37:44 pm

Mark(The Miser)UK

  • Veteran

  • Offline
  • ***

  • 1557
Re: Bearings on crank too big? Crank hard to turn by hand
« Reply #9 on: January 10, 2011, 12:37:44 pm »



If your problem is a misalignment one, ie crank bent, then only clamping one bearing at a time, will reveal this, and/or is every bearing binding the same?.. Which is a problem with the shells
Mark-The-Miser-UK

"There's nothing like driving past a bonfire and then realising; its my car on fire!"

I'm not here to help... I'm here to Pro-Volke"

Be like meeee: drive a Quantum TD
 ...The best work-horse after the cart...

Reply #10January 10, 2011, 01:14:30 pm

DCC

  • Junior

  • Offline
  • **

  • 184
Re: Bearings on crank too big? Crank hard to turn by hand
« Reply #10 on: January 10, 2011, 01:14:30 pm »
When I was working with a friend on a strange engine we were doing for his mk1 (basically a mix of G60 and 16v engine pieces with a turbo bolt on), we had the same issue. We measured and re-measured the bearings once and again, and it all seemed normal, as it had the same size as the original ones. We couldn't turn the crank at all.

After lots of scratching our heads we measured in groups of two, making the whole circumference () and we discovered a 0.01 cm difference between the new ones and the old ones. We got the wrong bearings (we were using G60 bearings on 16v connecting rods).

Reply #11January 10, 2011, 07:01:42 pm

kevinm

  • Junior

  • Offline
  • **

  • 78
Re: Bearings on crank too big? Crank hard to turn by hand
« Reply #11 on: January 10, 2011, 07:01:42 pm »
It would seem 2 and 4 are the ones holding me up, 2 slightly more than 4.  I can tighten 1,3 and 5 to spec torque and have the crank turn with ease.  Ill put the crank between centers tomorrow and take a look.  Thanks for the input everyone.

Reply #12January 10, 2011, 11:13:36 pm

Quantum TD

  • Veteran

  • Offline
  • ***

  • 1195
Re: Bearings on crank too big? Crank hard to turn by hand
« Reply #12 on: January 10, 2011, 11:13:36 pm »
It would seem 2 and 4 are the ones holding me up, 2 slightly more than 4.  I can tighten 1,3 and 5 to spec torque and have the crank turn with ease.  Ill put the crank between centers tomorrow and take a look.  Thanks for the input everyone.

That sounds like something bent or warped to me. Maybe try it again by swapping the actual bearings around?

Reply #13January 11, 2011, 05:02:27 am

Mark(The Miser)UK

  • Veteran

  • Offline
  • ***

  • 1557
Re: Bearings on crank too big? Crank hard to turn by hand
« Reply #13 on: January 11, 2011, 05:02:27 am »
It would seem 2 and 4 are the ones holding me up, 2 slightly more than 4.  I can tighten 1,3 and 5 to spec torque and have the crank turn with ease.  Ill put the crank between centers tomorrow and take a look.  Thanks for the input everyone.

That sounds like something bent or warped to me. Maybe try it again by swapping the actual bearings around?

Take that as a 'maybe'  bent "oh bringer of doom" ;)

OK this is what I'd do: Leave one of the faulty ones off, and gradually tighten the other whilst rotating  the crank to see if any tight spots. Tight all round? Remove shells, and insert the 'best' pair of your old shells. Do they work correctly? If they are greyed all over then simply leave them in. Alternately, either buy a bigger shell, or apply some fine grinding compound and with the new 'faulty' shells,  tightening until just starting to bind and then rotate crank a few times with a wrench. Remove, clean and recheck. Caution Do not tighten too much when abrading, so as to avoid scouring the crank. Repeat with other bearing.  In the absence of other new shells, I'd be inclined to reuse old ones if their condition is good...
Mark-The-Miser-UK

"There's nothing like driving past a bonfire and then realising; its my car on fire!"

I'm not here to help... I'm here to Pro-Volke"

Be like meeee: drive a Quantum TD
 ...The best work-horse after the cart...

Reply #14January 11, 2011, 06:53:23 am

kevinm

  • Junior

  • Offline
  • **

  • 78
Re: Bearings on crank too big? Crank hard to turn by hand
« Reply #14 on: January 11, 2011, 06:53:23 am »
I was thinking the same thing, use old shells on the problematic number #2 and #4... I found that it still wanted to bind however with my old shells, at least an old shell on the bottom bearing surface.  Im going to measure a few things today and maybe a line bore is in order if its not the crank...