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Wed Jun 08, 2005 11:54 pm

This is probably a stupid question. Can you install a sand seal when a engine is complete. Please let me know if this can be done. Thank You and have a great day!!

Thu Jun 09, 2005 8:18 am

Yes, if the case is already cut for one. If it's not machined for a sand seal, you can buy a kit that slips in the stock hole. I don't recommend the kit though, as the insert will spin and leak anyway. The case should be machined.
-John

Thu Jun 09, 2005 12:56 pm

Stupid question time. Just exactly what is a sand seal and is it needed for a street car. Obviously by the name, it's a requirement for off-road.

Thu Jun 09, 2005 1:19 pm

A stock crankshaft pulley has a series of spirals machined into the center portion that inserts into the VW case. I'm not sure what year that started or if when it has changed. The spirals act sort of like a fan that will drive a small amount of air (and dirt, sand, grit) back into the case. This along with the oil slinger that is just inside the case keep oil from seeping out of the case at the pully. Off road VW builders back in the day started machining a step in the case to accept an oil seal and turned the center of the crank pulley down to fit that seal.
Any time I build or rebuild an engine for the street or dirt, I machine the case for that seal. It just helps to keep junk from getting in right there.
-John

Thu Jun 09, 2005 1:22 pm

Come to think of it. I do remember hearing about a machine shop back in San Diego or Santee, CA that has a tool that will cut that groove while the motor is together. I'd be worried about metal shavings getting into the case though.

Thu Jun 09, 2005 1:24 pm

Thanks John!

Thu Jun 09, 2005 3:42 pm

i believe that the spirals in the pulley are designed to drive crap out of the motor, not in.

you should not need a sand seal on a street driven car that is set up correctly... remember that the crankcase is typically under a very mild pressure due to blowby.

Thu Jun 09, 2005 4:16 pm

danimal wrote: i believe that the spirals in the pulley are designed to drive crap out of the motor, not in.

you should not need a sand seal on a street driven car that is set up correctly... remember that the crankcase is typically under a very mild pressure due to blowby.

Dan, get a look at one.. the rotation spirals INTO the engine, which is what keeps the oil in. The blowby though, should be enough to keep stuff out of the engine. You're right.. Sand seals are for sand. I run one for peace of mind, but guess what.. mine leaks a little due to inferior pulley. lol what irony.

Thu Jun 09, 2005 4:50 pm

I had a slip in sand seal in my old motor,when i tried to put it in my new motor itwould not work. it fit fine evrything lines up ok but the pulley bottoms out on the seal whats up with that. neither case was machined for a seal. when it bottoms out of course the motor wouldnt turn over so i had to go back to stock, Iliked having the timing marks

Thu Jun 09, 2005 8:02 pm

mark, i'm not sure that we should be listening to a guy who had to install a sand seal because he didn't know enuf about pulley's to buy one with the proper o.d. on the shaft :wink: j/k

seriously, tho, the reason that the thread direction isn't a concern on type 1 pulleys is because none of the threads are exposed outside of the case, where the dirt is... all of the thread rotation action is well inside of the nose of the case, where it's surrounded by positive pressure from blowby... keeping the blowby from coming out the nose of the case is why the threads are spiraled the way that they are.

now for extra credit... how does a type 3 pulley differ from a type 1 pulley, in that respect?

dubster, check with gene berg to see if they have a sand seal cutter that'll work with the motor together.

Thu Jun 09, 2005 8:20 pm

danimal wrote: mark, i'm not sure that we should be listening to a guy who had to install a sand seal because he didn't know enuf about pulley's to buy one with the proper o.d. on the shaft :wink: j/k

Eh? You been breathin too much of that crap wafting up from your meth lab.

In retrospect, I should have bought a pulley that was hardened, or a steel one, and then had the proper OD put on the pulley (which I think was supposed to be 1.770". I had one done up that way, but it was a cheap ass Scat pulley that was made from soft aluminum. I've got a hardened one on the way with a new seal that should fix my leak. I'm betting there is a nice little ridge cut in the cheap ass one I have now. I know it came loose on me once, probably because the snout mushroomed. I hate cheap parts. Scat's got their name right. lol

John C's got a cutter you can rent for assembled engines. That's what I did.

Thu Jun 09, 2005 9:01 pm

i don't get it.

there are aftermarket pulley's out there that don't need to be turned down... and if it's made incorrectly on the o.d. of the shaft, then the i.d. could be off as well.

did the wobbly pulley damage the case hole? that could be a factor in the leak.

if you need a good power pulley, i have what i think is a genuine santana aluminum pulley that i'm never gonna use... if you can use it, let me know.

Thu Jun 09, 2005 9:17 pm

Well, it's a long story but it boils down to: the balance shop figured out my OEM pulley was warped, and I was going to have the OEM turned down, but since it was screwed, I needed another in a hurry, and he had a new one that was not already turned down, and he turned it down for me, rather than me have to wait for one to ship.

The ID is a little loose on it.. I just have to tug firmly on it to get it to come off, but it's not sloppy by any means, and I can't visually detect any runout on it.. the cut was pretty exact and nicely polished, but aluminum pulleys are known to groove sometimes, and I would guess that's what happened. I haven't had it off yet to see what all happened, but with the seal cut in, I can't imagine that the case hole could be remotely in contact with the pulley snout, especially turned down to 1.770.

If it comes to it, I will have this local shop I know of turn down a steel one for me. They do really nice work.

I appreciate the offer on the pulley, but I don't use the power pulleys. I may take you up on that if I switch over. Right now I keep my head temps at 325 and oil at 190-200 (hwy) and I'm trying to keep it that way at the expense of a few horsies.

Thu Jun 09, 2005 9:35 pm

that's exactly why i've never run this power pulley... a guy who used to work at a local vw dealership ran an ad in the paper for a stash of stuff he had, i managed to get the santana pulley and thing fan shroud before dave cormack got there, lol.

robert hemphill ran a power pulley for the longest time, it really freaked me out, but he's an avionics guy who monitors his temps really well... never cracked his heads, no engine damage, and he drives his stuff plenty hard... i'm still sticking to the full size pulley, tho.

Fri Jun 10, 2005 4:42 am

I run a slip in sand seal. I drilled two small holes thro the case and into the AL part holdoing the seal, then installed small roll pins to keep the seal in and from spining.

Fri Jun 10, 2005 7:11 am

Anybody torn down an offroad engine without the sand seal... and find any sand/grit?

Wonder if you get sand stuck in the grooves on the crank if its not scraping the ID of the case...

Seen them for sale but never really looked into them! 8)

Fri Jun 10, 2005 11:47 am

Thanks everyone for the info. Who is john c and where is he located at? James 2 where can you find that slip in sand seal at. Thanks everyone for all the help.

Fri Jun 10, 2005 12:29 pm

jamestwo wrote: I run a slip in sand seal. I drilled two small holes thro the case and into the AL part holdoing the seal, then installed small roll pins to keep the seal in and from spining. I like that idea. Does it seem to work good? No leaks?

Fri Jun 10, 2005 12:31 pm

vdubster wrote: Thanks everyone for the info. Who is john c and where is he located at? James 2 where can you find that slip in sand seal at. Thanks everyone for all the help.

dubsta, John C is www.aircooled.net

The tool rental: http://www.aircooled.net/new-bin/viewproductdetail.php?keyword2=TZE0028&cartid=

Fri Jun 10, 2005 2:09 pm

i have one of the berg sand seal cutters. its a no brainer. it slides on the crank nose and you use the bolt and some type of washer to draw it in as you turn the tool with a spanner. it has an o-ring on the inside edge which stops any shavings from getting into the motor and has a positive stop that only lets the tool go to the correct depth and no further.

i plan on trying it on a junk case before i ever do it on a good motor just to be safe.