-
Bearings on crank too big? Crank hard to turn by hand
by
kevinm
on 09 Jan, 2011 19:52
-
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.....
-
#1
by
Quantum TD
on 09 Jan, 2011 20:02
-
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)?
-
#2
by
kevinm
on 09 Jan, 2011 20:08
-
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.
-
#3
by
Vincent Waldon
on 09 Jan, 2011 20:37
-
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.
-
#4
by
kevinm
on 09 Jan, 2011 21:21
-
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.
-
#5
by
Vincent Waldon
on 09 Jan, 2011 21:36
-
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.
-
#6
by
truckinwagen
on 09 Jan, 2011 21:37
-
just to check(not that we all dont know already) which end of the motor is number one?
-
#7
by
Thezorn
on 10 Jan, 2011 01:17
-
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.
-
#8
by
R.O.R-2.0
on 10 Jan, 2011 08:19
-
my grandpa had a block like this. the block was no longer straight, and needed a line bore..
-
#9
by
Mark(The Miser)UK
on 10 Jan, 2011 12:37
-
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
-
#10
by
DCC
on 10 Jan, 2011 13:14
-
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).
-
#11
by
kevinm
on 10 Jan, 2011 19:01
-
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.
-
#12
by
Quantum TD
on 10 Jan, 2011 23:13
-
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?
-
#13
by
Mark(The Miser)UK
on 11 Jan, 2011 05:02
-
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...
-
#14
by
kevinm
on 11 Jan, 2011 06:53
-
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...