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Thu Feb 25, 2016 2:27 pm

77 Standard FI engine.

So, my issues with my "rebuilt" engine persist. The latest, when we got the (original) tin for just under the balancer pulley, and then installed it, the balancer hits the tin and the belt is skewed. The pulley "wlaks" all over when hand cranking the engine.
Removing the balancer, there is no seal on the crank shaft behind the balancer pulley. That just seems wrong.
I found a "Replacement Seal & Collar Bolt-In" that fits right into the space on the crankshaft, but then the seal just rubs against the back side of the pulley???

That back side of the pulley central shaft is threaded, like it needs something to screw into.

It simply makes no sense to me or the mechanic who is assembling the car for me. WE have more and more reservations about what the builder might have "forgotten" on the inside.

Thu Feb 25, 2016 2:37 pm

our pulley is not a harmonic balancer by definition- and there is an oil slinger and labyrinth seal cut into the hub of the pulley that effectively pumps any escaping oil back into the engine- so if its not leaking- don't fix it-

you might be referring to a sand seal- which is developed for dune buggies so they won't ingest sand on the dunes- these usually require a machining of the front of the case and shimming of the pulley along with a longer pulley bolt.

Thu Feb 25, 2016 2:50 pm

The pulley has a reverse type screw thread on the rear to discourage the oil from coming out further, and in fact to push it back in. :shock: Yep. The crankshaft has a curved flange to deflect the oil just inside the case in a little hollow with a oil return canal and this catches most of what would come out. There is no 'seal' on the pulley-side of the crankshaft. Normally they do not leak much here unless you have other problems. You can however get a 'sand-seal' as an aftermarket item to seal up the crank-to-case behind the pulley.

The pulley only goes on one way -there's a key on the crankshaft. You will have to make sure you are getting this lined up right and then use the safety washer and the nut to tighten the pulley in to position. The tin behind the pulley needs to go on under the other tins as far as I'm concerned - ie it's first on, last off. Perhaps you have it overlapping a bit or it is bent? Take a photo and post it up so we can see? Everything sounds normal except for the fitment of the pulley - and can you describe a bit better what you mean by the pulley 'walks around'?

Thu Feb 25, 2016 3:00 pm

Pulley "walking" means the pulley moves perpendicular to the crank shaft, like pulley was bent or something. Belt moves forward/backward as the pulley goes around. With the pulley off, placing it on a flat surface, there is no such wobble. Remember that comment about my worry about the internals :(

We are lining up the notch with the wood-whatever key on the crankshaft.

So those threads on the back are a way to get any leaking oil back into the shaft???? Freaking German engineers!!! (I'm 1/4 German)

Yeah, I got the sand seal.

The tin might be wrong, it went on last. . .

Thu Feb 25, 2016 3:57 pm

Pic of the engine without the pulley

Thu Feb 25, 2016 4:28 pm

unclewede wrote: Pulley "walking" means the pulley moves perpendicular to the crank shaft, like pulley was bent or something. Belt moves forward/backward as the pulley goes around. With the pulley off, placing it on a flat surface, there is no such wobble. Remember that comment about my worry about the internals :(

We are lining up the notch with the wood-whatever key on the crankshaft.

So those threads on the back are a way to get any leaking oil back into the shaft???? Freaking German engineers!!! (I'm 1/4 German)

Yeah, I got the sand seal.

The tin might be wrong, it went on last. . .

Ok, so the pulley is on at an angle... You must torque the pulley to 33ft/lbs. Do you have the washer between the bolt and the pulley?

Thu Feb 25, 2016 9:33 pm

laying pulley on flat surface only shows you the face surface of the pulley...if the face surface is bent at the hub....the pulley when spun will wobble as you describe

Fri Feb 26, 2016 3:37 pm

Those stock pulleys are typically pretty soft and can be straightened with a prybar between the pulley lip and the engine case. Nothing is perfect but you can get pretty close.

Wed Mar 02, 2016 3:43 pm

Got a new bolt/washer, both are installed.

I put both the larger pulley face AND the smaller end with the oil threading onto flat surfaces with no wobble there.

We went back to the aftermarket pulley with the numbers, as well as an extra washer around the crank. Just rotating the engine with a wrench I couldn't see the wobble but the 2 mechanics still could, so the engine is in and we are finishing connections. I want to see it at RPMs to decide now.

Wed Mar 02, 2016 5:11 pm

unclewede wrote: The latest, when we got the (original) tin for just under the balancer pulley, and then installed it, the balancer hits the tin and the belt is skewed. The pulley "wlaks" all over when hand cranking the engine.
<..>
That back side of the pulley central shaft is threaded, like it needs something to screw into.
You need to post more pics to show what you mean. Even if the two faces of the pulley are flat, if they are not parallel the pulley will wobble. Have you checked that both are parallel? Better yet, the shaft hole should be parallel with the fan belt groove.
The stock pulley can be easily ruined by forcing it off. They often get "welded" to the crank after decades of being there. When rebuilding an engine that has not been touched in decades (or worse left outside for years) you almost have to assume you will destroy the pulley during disassembly.

Many pulleys will have grooves on the OD of the nose to handle oil that drips on it. The grooves push the oil back into the engine.

unclewede wrote: Removing the balancer, there is no seal on the crank shaft behind the balancer pulley. That just seems wrong.
No seal needed because of the oil slinger inside the case deflects the oil outward so it drains back into the case. One less part to wear and start leaking oil.

unclewede wrote: I found a "Replacement Seal & Collar Bolt-In" that fits right into the space on the crankshaft, but then the seal just rubs against the back side of the pulley???
This sounds like a replacement "sand seal" which is meant to work with a specific type of "sand-seal pulley". As the name suggests the seal is meant to keep sand OUT of the engine. There are two types of sand-seal pulleys... ones that "bolt-in" and another type that must be "machined-in". Neither will work with a stock pulley. The grooves on the stock pulley would likely chew up the seals. The seals must be used with a special sand-seal pulley.

unclewede wrote: It simply makes no sense to me or the mechanic who is assembling the car for me. WE have more and more reservations about what the builder might have "forgotten" on the inside.
Hmm, is your mechanic familiar with air-cooled VWs? The sand-seal and pulley grooves are common traits of acvw engines.

Thu Mar 03, 2016 4:36 pm

The owner is a Porsche-certified mechanic. His dad "consults" on all the VW stuff, and then the guy in the trenches does all the wrenching.

I'm close to moving the thing over to another shop a few cities away where they specialize in VW.

It was a third-party rebuilder who did the original engine. The shop I dropped it at subbed it out to someone I've never met/interacted with directly.

Fri Mar 04, 2016 10:46 am

bad info on torque of pully bolt. my books read 101 ft lbs. since i don't have torque wrench reading that high' i use 2 ft helper bar and lots of lbs. never had one come loose.

Fri Mar 04, 2016 11:36 am

Rex lucy wrote: bad info on torque of pully bolt. my books read 101 ft lbs. since i don't have torque wrench reading that high' i use 2 ft helper bar and lots of lbs. never had one come loose.

There is absolutely no reason to torque the crank pulley bolt that high. Volkswagen (the company, not the Samba member,) built millions of these cars and never had one come loose either.

Fri Mar 04, 2016 3:52 pm

Rex lucy wrote: bad info on torque of pully bolt. my books read 101 ft lbs. since i don't have torque wrench reading that high' i use 2 ft helper bar and lots of lbs. never had one come loose.

Nonsense. What book says 101ft lbs?

Fri Mar 04, 2016 8:59 pm

bentley manual pg 141 recommends torque of pulley bolt as 94 to 108 ft lbs. i don't believe its wrong as haynes manual list it as 101 ft lbs. pls just use the manual. wish i had a wrench that list 101 ft lbs ,i would use it.
would someone want the page number on the haynes manual.

Fri Mar 04, 2016 9:14 pm

Rex lucy wrote: bentley manual pg 141 recommends torque of pulley bolt as 94 to 108 ft lbs. i don't believe its wrong as haynes manual list it as 101 ft lbs. pls just use the manual. wish i had a wrench that list 101 ft lbs ,i would use it.
would someone want the page number on the haynes manual.

Please take a photo of this and post it. As of right now, you're the only one in the world I've heard say that. But if it's in the Bentley, we could have a nice discussion. Otherwise you sound like the guy with the tin foil hat.

Fri Mar 04, 2016 9:25 pm

whats wrong asiab do you not have either manual to look it up yourself. do you really think i wear a tin foil hat. i'm retired for last 35 yrs and have hobby of rebuilding vw's for pleasure of which i've rebuilt over 40 engines.
if you cannot back up advice you give by manuals it would be better to refrain.

Fri Mar 04, 2016 9:52 pm

My Orange Bentley 1970-1979 on page 14 of the Engine section under photo says:

"Start the pulley on the crankshaft, then draw it into place with the center bolt. Torque the bolt to 4 to 5 mkg (29 to 36 ft. lb.)."

Fri Mar 04, 2016 10:00 pm

Rex lucy wrote: whats wrong asiab do you not have either manual to look it up yourself. do you really think i wear a tin foil hat. i'm retired for last 35 yrs and have hobby of rebuilding vw's for pleasure of which i've rebuilt over 40 engines.
if you cannot back up advice you give by manuals it would be better to refrain.

My Bentley manual says 29-36 lb/ft. I would like to have an actual discussion of torque values, but I demand that outlandish outliers be backed up with facts. Never having a pulley back off is not a fact, because I haven't either at 33 lb/ft. Show us, don't tell us.

Fri Mar 04, 2016 10:03 pm

GEX has built more than 40 engines.