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Oct 2, 2000 | 09:10 AM

gypsybill

Thread Starter

Senior User

Joined: Jun 1999

Posts: 140

Likes: 2

From: Bander, TX (Hill Country)

Noise

Not sure this is transmission related, but I have investigated and just about ruled out everything else. Vehicle: '64 F100 with a '70 351W mated to a '76 C4. Noise: When I drop it in gear (drive or reverse) when the engine is on high idle (just started), I get a sound that I can best describe as the very tips of a thin metal fan blade hitting a wire cage as I hold the brake to either back out or pull forward from the drive way. Once the engine is off the high idle, and it is not straining against the brake, no noise.

Second scenerio. From a standing start or very slow rolling start (under 5mph), if I accelerate at3/4 to full throttle, I get the same noise as described above, only louder and only until either the tire quits spinning or I reach 3500 to 4000 rpm.

The engine is not stock, but not wild.. cam has about 218/224 duration, 475/498 lift with assorted other things done to bring around 300-325 hp at the flywheel. Transmission was rebuilt (me and my brother-in-law mechanic) about 2 years ago and I put in a new stock torque converter at that time.

Any ideas??

Bill in Mobile
'64 F100 Shortbox ('70 351W/'76 C4)

Oct 2, 2000 | 11:55 PM

jbhf250

Elder User

Joined: Oct 1999

Posts: 917

Likes: 3

From: Kelseyville USA

Noise

My Guesses are....
1. crank shart end play is excessive and the ring gear is hitting the nose of the starter.
2. torque converter bolts are loose.

My .02

__JOHN__Õ¿ö
Member-
"Crusin North" Car Club
Santa Rosa, Calif.
72 F-250
ICQ#6030753
http://clubs.excite.com/72FORD-F-250

Oct 3, 2000 | 11:21 AM

PAUL_2

Postmaster

Joined: Jul 1999

Posts: 3,172

Likes: 4

Noise

I wonder since the noise sounds like fan blades hitting if that isnt what you are hearing ? In reverse the engine will roll slightly left & if the motor mount on the right side is broke it will allow enough flex for the fan blades to make contact with the shroud . Same applies if you are applying a lot of power going forward , if the mount(s) is broke it will alllow the fan to contact the shroud .

Oct 3, 2000 | 05:01 PM

gypsybill

Thread Starter

Senior User

Joined: Jun 1999

Posts: 140

Likes: 2

From: Bander, TX (Hill Country)

Noise

The engine was just put in (by me) and I replaced the motormount pads at that time... so that was the first place I looked to be sure I didnt leave one loose... I put tape on the inside of the shroud where the fan could possibly hit and tested.. no strikes on the tape.... plus this noise does not happen when just sitting and reving the engine... only under load... first I thought is was timing.. like to much and getting knock.. but that is set correctly.. even backed it down and still get the rattle (except it takes more throttle to spin the tire)...

I am going to pull the inspection plate off the tranny this weekend and check for loose torque converter bolts and any marks on the teeth of the flexplate...

The engine only has 2000 miles on it after a complete rebuild (blue printed/balanced/align bored/decked/etc/etc) by a very reputable speed shop.. so hopefully it isnt an end-play problem in the crank...

Thanks for the suggestions...

Bill