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Discussion Starter · #1 ·
Is it likely that my Falcoon engine has lost it's thrust bearing? I just replaced the Pilot Bushing because of the original one was wobbling and causing a driving vibration that shuldn't go away unless I was driving at 65 and sidestep the clutch, then it got better but not gone, therefore I changed the hugely overlarge pilot bushing today.

The first test drive of 4 miles up and back was great with only a little amount of low to mid rpm vibration (Note: This vibration is more audible than feelable, or was until now...)

The second test drive of 14 miles it got worse and worse, and now it vibrates at will but is even louder when turning the wheel Left....!....!

The Damn thing will start and idle without vibration until I put it in gear and move a tiny bit then it vibrates a lot again...

It's my belief that the flywheel is out of balance with the crank, maybe the 1970 Maverick crank in this motor was made for a friggin automatic...

I made sure the pilot bushing fit the shaft perfectly. Could the vibration come from the flywheel even though the vibration will go away if screwed with enough?

Could a bad Thrust Bearing on the crank allow this? I can grab the balancer pulley and move the crank fore and aft enough that I can see the movement with my naked eye, and hear it come to a stop either direction.

The oil is clean and without any aluminum/lead or copper flakes...

Anyone think the pilot shaft might be bent? I have a buyer coming tomorrow morning to try to buy it but I can't let it go like this... I'm going to take the damn tranny back out again and remove the whole flywheel assembly and take some mic measurements and then sit there and bitch and moan until I figure it out or someone chimes in with a bright Idea or two...
I got some Kellser's whiskey to help me on the way...


UPDATE:
Removed everything a few minutes ago and it all looks great. Even took the flywheel off and the play in the crank is less than 1mm by eyeballing it...

This bastard is bugging me to death.
THERE IS NO VIBRATION WHILE DRIVING IF I PRESS IN THE CLUTCH AND IDLE OR DROP IT INTO NEUTRAL... This HAS to be a Pressure plate issue but this one is near perfect...


FE
 

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I'm assuming you have a 302 and a Toploader. If the Toploader is originally from a 390, the input shaft is too short to fully engage the pilot bearing. An FE crank is longer in the piiot bearing flange so the trans input shaft is about 3/8"-1/2" shorter than a 302 input. They are otherwise identical (unless the fine spline 427 shaft). Reinstall the bellhousing and trans without the clutch or presure plate and with the fork removed. Look in and check if the input shaft nose is engaged in the pilot bearing. If it barely touches, you need a small block input shaft. I went through this on my 289 Cougar-converted from automatic. The toploader I got had the right ID tag for a 289 but someone had put a 390 input shaft in it. What a pain!
 

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Give us some more info about your car. What engine and year would help. Also, is this a combination that has ran before or have you been swapping parts?

No such thing as a SBF crank being balanced for an automatic vs. a manual.

The part of the input shaft that the throwout bearing ride on in a big block is approximately 3/4". For a small block it is approximately 1 1/16".

As mentioned the 390 shaft is the same diameter as a SBF. 427, 428, 429's used larger diameter shafts (still with a short input shaft.)

We really need more info to help.
 

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I believe he's running a 200 six with a three on the tree.Guess side stepping the clutch at 65MPH (probably top speed) didn't help matters. The car actually has 2 too many doors which is part of the problem. The vibration sounds like mismatched components to me.
 

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Gary ... might be worth checking the "Harmonic Damper" real close as well ...

I had the one on my work van go bad and the vibration was pretty evident (and even a bit intermitant) ... after we figured it out it seemed like it should have been obvious ... We checked everything but that first
 

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I once ran a toploader behind a 200. First toploader I bought was from a 390. It wouldn't down shift and eventually I tore up the main case because the input shaft never reached the pilot bearing in the case. Once I replaced the case, bearing and input shaft from a SBF, it worked well.

Irregardless, I just shot a pic so that everyone can tell the difference in a SBF toploader 4 speed vs. an FE toploader:



Does anyone have input as to which shaft is used behind a 385 engine?
_________________
Dennis

65' Stang

393W Stroker, Wide Toploader 4 Spd, 9" 3:70 Posi

Victor Jr. Heads, Stealth Intake, 750dp, 236/561 Solid Cam, 9.6CR, 1 3/4" Headers, Lakewood, Subframes, Caltracs



<font size=-1>[ This Message was edited by: dennis111 on 7/5/06 3:51am ]</font>
 

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Discussion Starter · #7 ·
The Falcon is a 1970 Maverick 200 straight 6 bored 40 over.

The tranny is a 25 pound 3 speed standard column shift.

The Harmonic balancer is solid and in great condition.

Sidestepping the clutch at IDLE while moving 65-70 MPH STOPPED 99% of the vibration and brought the noise level in the Falcon down enough to have a conversation without shouting.

Jim, the extra doors are for better aerodynamics....
Sheesh, I thought everyone knew that....

BRAND NEW PILOT CHAFT BUSHING, put it in last night and drove the car and the vibration got WORSE and it don't go away now. That's why I checked the fore and aft movement of the crank and found at or less than 1mm of movement,

The bushing fit's the pilot shaft perfectly and the crank perfectly.

I'm going out to put the clutch and tranny back in then drive it again, I'll drop more news should any arrive, and I'll check up here also....

remember fella's the vibration is likely in the flywheel area because it is RPM related not SPEED related.... Maybe I need to pull my pan and look, but the oil on the stick is gorgeous....

FE
 

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On 2006-07-04 19:53, FEandGoingBroke wrote:
it's worse than when I had a wobbled out pilot bushing.... And, the bastage never showed up to drive it anyway...


FE
You think he frequents FM at all?


 

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your clutch disk didn't lose a friction material pad did it?

You hadn't been treating it nice after all...

I'm just thinking it could be off balance, and like you said in another place, it slowly wobbles off center until you dump the clutch and line it back up.

<font size=-1>[ This Message was edited by: thekingofazle on 7/6/06 1:58am ]</font>
 

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Maybe input bearings on the tranny going bad, causing the input shaft to wobble? Maybe a nice roller pilot bearing would keep things in line better.
 

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Gary , if you are using the small 144/170 transmission, throw it away and put the larger trans. in that was used on the on the 200/250 engines. The small trans were notorious for wearing the needle bearings out. Have you taken the throw-out bearing slide cover off the front main drive and checked for play?? (up and down, and side ways)

I have two of those transmissiona in my junk pile because of that problem..
 

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Discussion Starter · #17 ·
Where the hell can I get one of those? I had no idea that this tiny little 30 pound tranny had a big brother of the same ilk.

Anyone have one handy and cheap?

Ray, PM pe and throw me your phone # so I can chat with you about it this weekend and maybe toss some ideas around on a cheap fix...

Gary
 

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On 2006-07-08 02:01, FEandGoingBroke wrote:
Where the hell can I get one of those? I had no idea that this tiny little 30 pound tranny had a big brother of the same ilk.

Anyone have one handy and cheap?

Ray, PM pe and throw me your phone # so I can chat with you about it this weekend and maybe toss some ideas around on a cheap fix...

Gary
Ah, now you might be on to something if you think the tranny is the problem.

You can swap the bigger 3 (or 4) speed easily. The tranny can be from a 67 or later 6 banger or most any year/model small block V8. The 66' and earlier 6 banger trannies are all the small version, like you have so forget them.

I've done the conversion on a 66' 200 (similiar to your 70 Maverick) and used the flywheel, pressure plate, clutch disk, throw out bearing, and bellhousing from a 6 banger Maverick. You would also need to purchase a new pilot shaft bushing for the big tranny. Could have used 67' and newer 6 banger Mustang (or Falcon/Comet) stuff instead, but the Maverick/Comet parts were readily available in junk yards at the time.

Next issue would be the driveshaft--the output shaft has different splines than the small 6 banger stuff. I assume you are using a small 4 lug rear axle in your Falcon. You would either need to find a yoke that matches your small driveshaft (NO conversion U Joints are available to match a small driveshaft to a large tranny yoke) or you would need either to replace the rear axle flange with one that would accept the larger 6 or a V8 driveshaft (that is how I did it.) I think it was from a Pinto. . . .That was 25 years ago so I am fuzzy on the donor. . . .Come to think of it, I think the 6 cylinder Maverick used a small driveshaft and it had the Falcon type 4 bolt wheels. . . .

Of course you would still have shifter issues to as the rod kits will be different between the 2 trannies. . . . . I bought a Hurst shifter for my Mustang conversion.

_________________
Dennis

65' Stang

393W Stroker, Wide Toploader 4 Spd, 9" 3:70 Posi

Victor Jr. Heads, Stealth Intake, 750dp, 236/561 Solid Cam, 9.6CR, 1 3/4" Headers, Lakewood, Subframes, Caltracs




<font size=-1>[ This Message was edited by: dennis111 on 7/9/06 6:13pm ]</font>
 

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I have used a Chebby joint , that have a small journal on one side, and a large journal on the other. The last one that I used was matched up at Advance Auto Parts.
 
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