billthe3

So after having a fun time killing the seal for the lower balance shaft by trying to jam it into the upper balance shaft housing, I found out that all three metal races I recieved in my front seal kit do not fit on either balance shaft. The old races slide on and off without issue, and spin freely on the shafts.

Is it possible that the races are the wrong size? Or are they supposed to be tight on the shaft and not able to spin? If so, what is the best way to get the new races on with the housing and seals?

TIA.

FRporscheman

Very, very carefully, gently, and slowly, run your fingernail over the whole surface of the BS shaft (where the bearings go) and feel for mars or burrs. Also do a visual check for rough spots. Clean any imperfections with fine sandpaper, being very cautious. When putting the bearing on, use some clean, light-weight oil.

Don't forget the clear mylar washers!

billthe3

Where do the washers go - the inner or outer side of the races?

The races will fit onto the end of the balance shafts, but it is almost like they narrow down because the race will only get about half to 2/3 on before it gets stuck on the end of the shaft and is unable to get any farther. I've already cleaned the ends of the shafts and all three races with fine sand paper, so there should be no burs. It just seems like the races are several thousands of an inch too small.


My question as to whether or not the race is supposed to be able to spin on the balance shaft was because I'm wondering if these are something that I could heat up to get them to slide on the shaft and then let them cool in position (and assumingly become stuck on the shaft).

Legoland951

Take a picture. What race are you talking about? There are no roller bearings or anything like that for a race in the balance shaft assembly so are you talking about the outer rim of the seals themselves? I don't remember any metal parts in the reseal kit for the balance shafts.

tyro

I think Bill is talking about the highlighted parts in this diagram.

I'm not sure why the fit is off, are your old ones unusable (have a groove worn in where seal/spacer make contact)?

The spacers in my engine spun freely, and didn't leak.

Are you sure that you're putting them on in the right direction (flange side in)?

ibkevin

My latest lower bs race, just enough to catch a nail on.

The oil pump drive sleeve is famous for this also.

Legoland951

Those spacers do not come with any reseal kit I have seen. I believe you would have to specifically order it. If you are having problems putting them in, look for nicks on the woodruff key slots on the balance shafts. There may be rust or metal deformation from previous owner hammering a screwdriver into it to remove them.

87944turbo

Zim's sells the races with their deluxe seal kit (http://www.allzim.com/acatalog/Delux...944_944T.html). Not sure if this is the one he purchased, but I have run into similar issues with this kit. In my case it took a little extra time sanding to get everything to fit. And I would think that the races do turn with the BS shafts rather than the shaft turning inside the race.

billthe3

Yeah, I ordered the zim's kit. The oil pump sleeve didn't have any issues going on. The old ones have noticable notches worn in them from the old seal, enough to catch your fingernail.

So after I recheck the shafts for any notches/burrs/marks, it sounds like I get to sand them down till they fit?

Jay W

Sand mostly in the area of the woodruff key slot area. I have had several that had high edges which caught the new races and kept them from sliding on. The mylar washer goes on before the race goes on.

87944turbo

That's what I did. Seems like two were fine but one needed quite a bit of work. Not ideal, but the cost of the entire deluxe seal kit is pretty close to the cost of a single race at some other vendors. I guess you get what you pay for. Been on for about 700 miles or so and no leaks

billthe3

Wait, just to check, am I sanding down the balance shaft or the races?

87944turbo

The inside of the races until they fit over the BS like the old ones did.

Sanding down the shafts would be a one shot deal.

ibkevin

Standard Engineering rule, always modify the most insepensive and easyiest to replace part first.

billthe3

With the amount that it looks like I'd have to remove from these races to fit the balance shafts, I'm considering just reusing the original races. Seeing as it seems that most people don't replace these races when they do the front seals, I assume this would be acceptable if the races aren't in too bad of condition?