Front Drive Shaft Yoke Hitting Tunnel

[KenF]

Lately I've noticed when under hard acceleration a little thumping sound from the driveshaft. Checked the rear, all looked good there. Looked up front and apparently the front driveshaft yoke is hitting the tunnel. The clearance between the yoke and the tunnel is around an 1/8" on the right side but obviously moving to the right and hitting tunnel. I loosened up the rear mount bolts and pried the tranny towards center while tightening the bolts back up to gain a fraction of an inch, and doesn't make any noise for now. Rear mount seems to be in good condition, new Spicer u-joints, new tail shaft yoke bearing. I'm tempted to slot the bolt holes on the mount to get another 1/8" clearance. Has anyone else seen this?

Thanks, Ken

 

[at the beach]

Rootes chose to not place the center of the diff on the centerline of the the car. It's offset to the right side (or passenger side on LDH Tigers). This leaves very little clearance on that side. (this decision allowed the Tiger to use the same axle on either side, lessening the number of spare parts needed to be stocked by Rootes dealers.)

Could something have happened in your rear to shift it more towards the right?

I once had a U-joint "thumping" problem after we had some rear end work done. An incorrect differential yoke (too short) was installed. This caused the foward "U"-joint to slide more rearwards to a place where it could hit when being thrashed around at Laguna Seca. My wife crawled under and spotted where the paint had been scraped off by the U-joint. We inserted a spacer to move the U-joint forward before the next race weekend.

 

[Bryan]

your tunnel show have the rootes hammer adjustment dents- maybe yours was missed

 

[KenF]

Could something have happened in your rear to shift it more towards the right?

Not that I know of. Removed rear end housing last year, pretty sure it's sitting where it's suppose to be on the leaf springs. Housing U-bolts are torqued correctly. Car tracks straight down the road. Haven't done any donuts recently! Kidding, it's a warmed over 260, unlikely. I'll take a closer look next time I pull the motor and trans, got a slow oil leak I want to fix anyway. Looked at other Tiger photos and seen others that are pretty close to the tunnel too, some more than others. It's working fine since the sideways adjustment. Wife and I took it on a 150 mile drive up highway 49 to the wine country and Placerville yesterday, nice ride, and no noise from the driveshaft.

 

[ojxxx]

Take a look at motor & trans mounts to see if the rubber is disintegrating allowing some shifting in the driveline. These are rear motormounts from a Nash Healey I pulled out, they let the rear drop an inch and the torque tube was resting on the rear crossmember.