[Justshootme84]

Need some adivce on a project. We recently swapped a 4-sp manual back into a 66 Mustang that had a C6 behind the 289. Ther is now a vibration in the motor when you rev it up, and I believe it's the flywheel. Currently chekcing the casting number on the engine, but want to know if we're on the right track with the flywheel or if it could be something else. the vibration was not there before, and is very noticeable thru the steering wheel when you rev up to 2000 rpm's or higher. The flywheel is supposed to be for a 68 model engine (28oz), JSM84

[Yardape]

The flywheels are all the same i'm sure. 302's changed in 83 so your 289 should be fine. I wonder if the flywheel has to be balanced with the harmonic balancer. You did remember the pilot bushing in the back of the crank I hope. That would case a vibration.

[BroncoJoe19]

I swapped out a few clutch plates in my day, and never bothered to have the flywheel turned or for that matter even surface sanded or ground, but that was a pretty standard proceedure.
The clutch plate also gets bolted right onto the flywheel. doesn't it? If thats not new, or warped, that could give a vibration too, no?

[Justshootme84]

Yes, yardape, I thought too that maybe the new pilot bearing may be installed wrong or causing a problem. And the new flywheel came with a motor plate, which is a 1/8"-thick spacer bewtwwen the bellhousing and block. It looks like the engine casting number is "D50E", which comes back as a 75 Torino. But I don't know of any Torino's with a 289/ 302? The skeeter wer so dang bad we had to spray the shop for'em. so hope today that I can get anothe look at the numbers, JSM84

[BroncoJoe19]

JSM84
I must be missing something here.
This engine and flywheel ran without a vibration before ?

So you disconnected a C6 tranny (which is an auto tranny right?)

And you put in a manual tranny. Right?

Am I wrong here?.. The last clutch I put in was in my 1967 cougar around 1973, doesn't the pressure plate bolt onto the flywheel? I really don't remember.

If I'm right, then wouldn't the vibration be more likely a result of the pressure plate instead of a flywheel that was known to be good? Maybe it (the pressure plate) is out of balance? Could it be torqued on unevenly and cause a little warping of the flywheel, like when lug nuts are torqued unevenly it can warp a rotor?

[Justshootme84]

Yes, to recap. It's a 66 Mustang coupe, with a non-original 289/302 and C6 auto. The C6 took a dump, and the stang originally had a manual in it. Pulled the C6 and dropped in a 4-speed toploader from a friend's circle track parts car. Taking another look at the casting numbers comes up with:

D9OE-8015-E3A

This decodes out to a 79 Ford LTD II car 5.0L (302) V8. Since this engine was mated to a C6 auto, it had a flexplate with a large counterweight welded near the ring gear for balance. To do the manual tranny swap, We installed a new clutch, disc, pressure plate and piolt bearing along with the flywheel, all for a 67 Mustang. tihs was just taking a stab at what motor was in the mustang.

I think this is a fairly common problem when swapping from an auto to a manual, due to the type of crankshaft in the motor. While all of the Ford smallblock V8's pre-79 use a 28 oz imbalance flywheel if they're not internal balanced, a 50 oz flywheel was used with 80 up motors mated to a manual tranny. So, the only two options we have are to try a newer 50 oz flywheel, or bolt on a neutral-balance one.
That's where we're at for the moment, trying to locate a 157-tooth ring gear, 50 oz imbalance flywheel for a 80-up 302 V8. JSM84

[BroncoJoe19]

Thanks... I misunderstood.

[Crude dude]

Unclear about the previous answer about the new parts...was the flywheel new? I remember that my flywheel had a strange casting on the engine side of it. I bet that the counterweight is cast into the flywheel. I had hell on my Bronco going from manual to auto because most shops do not take the time to know the facts about crankshaft balancing. The crankshafts are the same for a manual or automatic but the flywheel is balanced with the front balancer. With an auto I ran into problems because the flywheel/ring gear, balancer and torque converter had to match. I bet you did bolt the wrong flywheel up to the engine and I do not know if a Fluidampr will correct that problem. Its not fun when you have to do it twice, let us know what you find.

[Justshootme84]

yes, the flywheel, clutch disc and pressure plate, pilot bearing and harmonic balance are all new. The flywheel does have a wedge in the back side for the counter-weight. the bellhousing is not new, but doesn't seem to play into the problem. The old harm balancer we removed is for a 50 oz. imbalance flexplate, and the old flexplate is def. a 50 oz. Just ordered a new flywheel from JEG's for $80, should be here Mon/Tues.

[Justshootme84]

Awesome!!! Put evrything back together last weekend, and NO vibration... This little baby is a real handful now. Need advice on how to fix the speedometer cable from the C6 to the 4-sp manual. Do I just need to swap the gear inside the tailhousing? JSM84

[Crude dude]

This reply might come up twice. oops. Good deal on conquering the vibration!! I am not sure about the speedo cable gear but have you checked to see if it will go into the trans? It may work without changes to the gear inside the transmission. The speed may be off but if it works then you can get an idea what gear you will need to replace it with. Let us know what you find.

[Justshootme84]

No, the end of the cable will not fit the manual tranny speedo location. I also thought this is all I had to do, but now I'm lost.

Edit: Did some work tonight. The cable still had the old gear attached to it, duh. It's orange, with 19 teeth. That's what came out of the C6 auto, and it's not compatible with the 4-sp top=loader tranny. Looking thru a catalog, I see a 7-tooth grear for the TL only, that may be all I need, JSM84

[bingen]

justshootme84...no we don't need to shoot you. Had a similar problem with my toyota cruzr when I replaced a 3 speed with a 4 speed from a dyna, including tcase (bolted right up). It developed a vibration. Broke my tcase.
Found out the I had pushed the angle to much from the tcase to rear diff. So we modified the new crossmember under the tcase to lower it and reduce the angle...vibration disappeared.
Best way to find the angle was to make the thing hang comfortably and then set you crossmember and mounts to support at that position....
Bud -A-Bing

[Johnny Reb]

#1-the automatic flywheel is different then a manual flywheel--in thickness and weight(MANUAL) yOU can not USE A AUTO MATIC --WITH A MANUAL TRANSMISSION. Anytime you put a manual transmission in(its best not to have someone talking to you) check the pilot bearing . If the vehicle had a automatic and you are putting in a manual transmission-you will have to get a manual transmission pilot bearing. wHEN YOU PUT IT IN ,THEN THE FLY WHEEL. mAKE SURE YOU TIGHTEN THE BOLTS AND DOUBLE CHECK. tHEN YOU PUIT IN THE CLUTCH AND FLYWHEEL(HOPEFULL YOU HAVE A ALIGHMENT TOOL-THEY CAN SAVE YOU TIME-IT LINES THE PILOT BEARING AND CLUTCH UP--TO MAKE SURE IT IS CENTERED)AND ALSO DOUBLE CHECK THAT THE PRESSURE PLATE BOLTS ARE TIGHT.The put the cross membe r(if it has one-some don,t)and your drive shaft. I was puttin in a new clutch in my fairlane one time and a friend came buy and got to talking and YES-I FORGOT TO TIGHTEN THE PRESSURE PLATE BOLTS. I told him to leave and come back in 30 minutes-so I could get my bolts toghtened.Hey, that is what friends are for.Good luck
-----OH--------AND PLEASE-WHEN YOU START THE TRANSMISSION IN--MAKE SURE YOU HAVE THE THROW OUT BEARIONG ON AND THE FORKS -THAT WORK YOUR CLUTCH---YOU ALSO WANT TO CHECK TO MAKE SURE THE---- THROW OUT BEARING ----IS GOOD. nO MORE THEN THE COST-GET A NEW ONE

[Yardape]

All that info probably would have been more beneficial back in September, haha

This post has been edited by Yardape: 18 January 2009 - 09:09 PM

[Johnny Reb]

Yardape, on Jan 18 2009, 09:09 PM, said:

All that info probably would have been more beneficial back in September, haha

yes, but some people do not have a place to get in out of bad weather and have to postpone things -until better weather permits .

[Justshootme84]

Update: Engine runs like a top, no more problems with it or the tranny. Found the right speedo gear after trying out a few. Got the speedometer to work, but it was 10-15 mph off. Went up in tooth count, and it got worse. Went back down, and it's reading true now. Also, finally figured out (hopefully) the problem with repeated broken rear driveshaft u-joints at the rear axle. The pinion yoke was badly worn. Ordered a new one last week. Back on the road, leaving black marks again. Did find out something new to me. The rear axle looks just like a Ford 9", but is actually a Ford 8" instead. JSM84

[Crude dude]

Easy way to tell the 8" from 9" rearend is by looking at the bottom bolt. If you can put a socket on the nut "like a normal human being" then its an 8". If you need a wrench its a 9".