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3A rebuild?



I've had 4 VW engines apart in the last couple months.
PL of unknown mileage that I suspect had the piss beat out of it.
ABA with about 100K
Two JH's with about 140K that had both seen service in my nephew's turbo car
at one time or another and had severe blowby when they were removed.
Basically, they all looked amazing good inside. Bores not worn out, bearing
journals all in good, if in some cases not great, condition. Even the
pistons didn't look bad with the exception of some minor scuffing on the
thrust face of the piston skirt.
Based on that, if your engine had reasonable care, I would bet that you'd be
able to use the crank and rods as is. Looking at the bearing shells that
come out of the engine will be a big clue. If the tin/lead material is wiped
away and you see large portions of copper then the bearings are overly worn
and the crank might be also. If not, perhaps polish the journals a little
depending on condition.  New bearings of course and you'd want to plastigage
them to make sure clearance is good.
If the bores are not worn i.e. there is no significate ridge at the top of
the bore (after you clean all the carbon off the very top) and the piston
rings meet spec on side clearance in the groove (and all the ones I took
apart did!) then I would suspect you could have a fine engine by simply
using a glaze breaker on the cylinders and installing new rings. You'd want
to use stock size rings (measure the piston to make sure it's not already an
oversize) and you'd also want to set your ring end gap per the Bentley.
Oversize rings in a stock bore will just have a real small end gap that
would need to be corrected.
Keep in mind there are wear limits on the various clearances in the Bentley
and you'd want to adhere to this worst case. If the piston to cylinder
clearance is outside the wear limit then it's time for new pistons. Same if
the ring side gaps in the grooves are too large.
In this case it's time for an overbore. The only machining that has to be
done in this case is boring and honing the cylinders. If you want to go nuts
you can get it line bored, decked, rods reconditioned, new aux shaft
bearings. But I bet your engine won't need this.
No sleeves necessary. Sleeves, in this case would only be used to save a
badly damaged bore, but why bother? Get another block
Some engines are designed with removable sleeves/cylinders such as Ferraris
and Porsches. In our case the bore is just a hole in the cylinder block
casting.
Parts list as follows:
      Part, Qty, price each, price total
      Pistons ring set 1 $61.95  $61.95
      Headgasket set  1 $53.55  $53.55
      Head bolts  10 $2.36  $23.60
      Connecting rod bolts  8 $3.20  $25.60
      Connecting rod nut  8 $0.63  $5.04
      Block gasket set  1 $44.10  $44.10
      Main bearings  1 $33.50  $33.50
      Rod bearings  1 $23.10  $23.10
      Timing belt  1 $7.35  $7.35
      Crankshaft sprocket 1 $20.16  $20.16
      Exhaust studs  8 $0.65  $5.20
      Exhaust nuts  8 $0.30  $2.40
      Passenger side engine mount  1 $19.95  $19.95

You may or may not need the crankshaft sprocket or the engine mount, 
but......
If you need to over bore the pistons are in the $400-500 range and you'd 
need to add machining costs. I recently paid $46, but had quotes as high as 
$125.
The above prices are from German Auto, but I'm sure parts4vws will be in the 
same range. Make sure whoever you buy the parts from know you're putting a 
1.8 JH head on a 3A block so you get the right gaskets.
So, that's all I know.
Dan


> From: "Gordy Stedman" <ydrogs@gmail.com>
> Sent: Tuesday, August 09, 2005 2:51 AM
>
> The 3A I got recently emits blue smoke out of the tail pipe and has
> 180k original miles on it.  Compresion test was between 195-180 on all
> 4.  Tried to do a leak down test but buddy did not have all the right
> equipment.  I am guessing the rings are bad and oil is being burnt.  I
> am going to swap out my 1.8L in my car right now and use the JH head
> with the 3A.  I know very little about bottom ends.  If the rings are
> bad do I need to get the block bored out and will it need sleeves?  Do
> I need to buy new oversized pistons and rings or do they make
> oversized rings that will work with existing pistons?  If it needs to
> get disassembled and go to a machine shop should I look at finding a
> different crank, rods or pistons?  I do not want to spend a lot of
> money and need it to be reliable and able to pass emissions test but
> am always looking for a few extra ponies.  Anyone ever do this and
> have a ball park price?  Thanks for your help.
>
> -- 
> Gordy
> MK1 x 3
> Audi 80 - Going under the knife
>
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