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Sat Dec 23, 2017 10:33 am

I'm considering buying a 1776cc motor that has ovaled out crankshaft dowel holes...I was wondering what should I offer the seller he is asking $250 minus the heads and what causes the dowel holes to oval and could the bearings or inner case be damaged as a result? I have never dealt with this issue

Thanks in advance

Sat Dec 23, 2017 10:34 am

Better figure a new crank shaft and rebuild.

Sat Dec 23, 2017 10:42 am

depending on how ovaled they are they can be repaired by going to larger dowels.Mine came loose suddenly i shut it off and had my machinist go larger and wedgemated the f/w crank 7 years ago

Sat Dec 23, 2017 10:43 am

gt1953 wrote: Better figure a new crank shaft and rebuild.

Definetly my thoughts...just don't want to buy an engine that may not be buildable...I guess the only real way to tell is buy it and hope :-)

Sat Dec 23, 2017 10:45 am

77charger wrote: depending on how ovaled they are they can be repaired by going to larger dowels.Mine came loose suddenly i shut it off and had my machinist go larger and wedgemated the f/w crank 7 years ago

They don't look bad at all...he is throwing in a crank as well

Sat Dec 23, 2017 10:47 am

One cause of oval holes is the far too common method of drilling the crank and flywheel separately. The right way is to drill and ream the two bolted together as a unit. I would NEVER buy a crank with the 8 dowels already installed(often dowels can very difficult to remove). The gland nut too loose is also very common.

Dan

Sat Dec 23, 2017 5:52 pm

Sometimes they can be repaired, but that's that's way too much for a used shortblock w/ wallowed-out dowels (aka: thrown flywheel).

Sat Dec 23, 2017 5:57 pm

The most common cause of that is the big nut wasn't torqued proper.
On more powerful engines it becomes more of a problem, if the fit of the crank to flywheel isn't good you can end up the same way even with the nut torqued proper. The cost of repairing the crank is probably the same as what the crank is worth, so as it is, the crank is worth nothing sorry to say. So, I suppose the price should be whatever you think it's worth minus crank and flywheel.

Sat Dec 23, 2017 9:20 pm

cw crank or std crank? std... no reason to fix it....just but a stroker crank and go with the strokes. if it's a expensive /good crank send it to Hose A at dpr... but 1776....probably a stock crank. and case may be poop too....Inspection tyme.

Sat Dec 23, 2017 9:21 pm

250.00 w/ the heads will be my only deal. :D

If it is ovaled badly, you are talking fresher crank and teardown.

Sat Dec 23, 2017 11:18 pm

Many, many years ago I bought a 64 bus with a running engine, but it came with another "fresh rebuild" longblock that had the flywheel come loose with less than 500 miles on it. The loose flywheel wrecked the dowel holes. I tore apart the fresh rebuild, had the crank and flywheel "eight doweled", then built it back up. It was a stock 1600 SP that ended up going 190K miles in a 74 bug that I sold to a gal that did rural newspaper deliveries.

If the engine in question is still only 4 dowels, get it drilled for eight, use the four new ones, and drive on!

Sun Dec 24, 2017 1:11 am

cdennisg wrote: Many, many years ago I bought a 64 bus with a running engine, but it came with another "fresh rebuild" longblock that had the flywheel come loose with less than 500 miles on it. The loose flywheel wrecked the dowel holes. I tore apart the fresh rebuild, had the crank and flywheel "eight doweled", then built it back up. It was a stock 1600 SP that ended up going 190K miles in a 74 bug that I sold to a gal that did rural newspaper deliveries.

If the engine in question is still only 4 dowels, get it drilled for eight, use the four new ones, and drive on!

You give me hope... I'm still contemplating it

Sun Dec 24, 2017 6:44 am

I’ve redrilled a 4 doweled crank as well. It was in a stock app and I was just a poor kid... but I was able to keep on driving and eventually did a rebuild with a new crank when I could afford it.

Sun Dec 24, 2017 8:56 am

cdennisg wrote: If the engine in question is still only 4 dowels, get it drilled for eight, use the four new ones, and drive on!

I've never come across this personally, but I believe that the above is the general fix.

I'm not sure that drilling out the holes for a wider dowel would not be an alternative fix.

O'Reilly has a free loaner 0 - 250 ft lb click torque wrench that I would recommend for the gland nut tightness.

Sun Dec 24, 2017 9:22 am

Here is a pic of the crank that has the dowel holes ovaled

Sun Dec 24, 2017 9:27 am

Those look really hammered. Not sure that oversized dowels would work there. Get it (and the flywheel) eight doweled, and maybe faced to remove any material that was pushed out from those old holes. Then just use the new four holes in your crank and flywheel with new dowels and you should be fine.

Use a known good or nice new gland nut and make sure to torque it properly. Some red loctite on good clean threads is a must, too.

Sun Dec 24, 2017 9:28 am

If you're close to a VW shop that can drill a crank/flywheel for 8 dowels, this could be an easy fix. Break it all down, deliver to them for the repair. You could just run it using the 4 new holes, or have them drill the bad 4 oversize for 11/32 dowels. If you're reasonably capable, you could do it yourself I bet. I did one using a drill press, which was kind of a PITA but it worked. Having a little guidance from people smarter than me was they key; particularly the suggestion to drill both as an assembly. I used a slightly undersize bit, and then used a reamer till the dowels fit well.
If you aren't close to a shop to do it for you, or willing to try yourself then budget for a replacement crank and flywheel.
SD

Fri Dec 29, 2017 9:13 am

Agree, seriously hammered.
Suggest checking those internal threads w/ a new, or known good gland nut: if there's any drag/binding/hang-up, consider this fact as another nail for the coffin.
Also ask the seller what grind/size the crank journals are. If she's already @ -.030", the wallowed-out dowel pins are a moot point.

Fri Dec 29, 2017 9:39 am

The other thing you need to look at is whether the align bore or thrust cut is OK. That will depend on how long it was driven with the flywheel wobbling all over the place.

BTW, I would never attempt to fix or use a crank like that. Cranks are cheap compared to the motor blowing up.

Fri Dec 29, 2017 9:44 am

Just drill new holes and get a new flywheel.

Use a 8 dowel jig to align the new holes and only use the 4 new holes to hold the flywheel.