Transmission Front Cover - 55 KHK

[Mayday53]

We completed the rebuild of the transmission on the 55 KHK, but as we try to put the transmission front cover (Part No. 34951-54) on, we noticed our center screw (part no. 34957-52) is about 3/8" short. I thought we must have misplaced the original, so I ordered a NOS (part no. 34957-52) from Tom's and it is the same length. I must assume I am missing something...

Anyone know what the heck am I missing, I cannot tell by the SPC (page 9) exploded view. Is there another piece between the crankcase and the screw?

We did have to replace the cracked transmission access cover assembly, could that be the culprit; i.e. the female threading extension is missing or something?

I appreciate anyone with experience sharing info...

[thefrenchowl]

I seem to remember the KH trap door for the conical dowel has a higher post for that screw than the later Sportster door...

And KH long screw should be longer than K long screw, the cover is deeper to accommodate the wider 7 plate clutch assembly...

Order a Spotster screw, it should be a tad longer...

Patrick

[Mayday53]

YOu may be spot on when I looked at the two doors it appeared you were right. Tom's is sending me the Sportster cover screw kit as it appears to be the right length.

[thefrenchowl]

Hi, for reference:

Trap door differences between -54 on top, 6 bolts/conical dowel KH and -54 A, early Sportster, 4 bolts/straight dowel:



Patrick

[EKHKHK56]

So you need to make a support spacer to make up difference along with longer bolt.

[Mayday53]

So you need to make a support spacer to make up difference along with longer bolt.

Are you saying a space equivalent to this (see circled)? If so, what purpose does it have, structural stability?

53 Trap Door.JPG (151.85 KiB) Viewed 15820 times

[EKHKHK56]

I need to looking at a cover later. If it did have spacer support it would be good to reinstate. Was going by memory

[thefrenchowl]

There's supposed to be a gap there anyway, and its width does not matter cause if there's no gap, there's no way the cover outer lip will seal with the cases when you tighten the 3 screws...

My guess: the cover went deeper on the KH, but to use the same screw as on K, they made the post on the trap door a touch higher than on the K case...

Reworked when the Sportster came...

Patrick

[Mayday53]

There's supposed to be a gap there anyway, and its width does not matter cause if there's no gap, there's no way the cover outer lip will seal with the cases when you tighten the 3 screws...

My guess: the cover went deeper on the KH, but to use the same screw as on K, they made the post on the trap door a touch higher than on the K case...

Reworked when the Sportster came...

Patrick

Patrick, I am confused (likely just me) on what gap are you talking about?

[thefrenchowl]

The gap between the end of the screw guide in the cover and the post on the trap door... If there's no gap there, there's no way you can make your cover oil tight...