Testing rebuild transmission

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rjkoop
Posts: 976
Joined: Thu Nov 08, 2012 6:45 am
Your car is a: 1981 Fiat Spider
Location: Ottawa, Ontario, Canada

Re: Testing rebuild transmission

Post by rjkoop »

Dave/Bryan,
Thanks for the advice and detailed explanations. I found it really helps to understand how things actually work with the clutch to know what may have gone wrong.

A few questions...

1. I removed the bell housing (I think that's where the leak was coming from... or the pan... hard to tell). The paper gasket got destroyed. Can I use ultra copper gasket maker to reform a gasket? I find those paper gasket are so thin and didn't feel like waiting a week to get a new one. Same goes for the transmission pan gasket. Haven't taken it off yet but I probably will have to.

2. What's spline grease exactly? I know only to use a small amount but can't feel to find that at my parts store.

Although I was happy that the 30 seconds I moved the car up and down the driveway 1st gear and reverse worked fine... except for the smoke and squealing. :D

Richard
18Fiatsandcounting
Posts: 3799
Joined: Fri Mar 15, 2019 11:23 pm
Your car is a: 1969 and 1971 124 spiders
Location: San Francisco Bay Area

Re: Testing rebuild transmission

Post by 18Fiatsandcounting »

rjkoop wrote:A few questions...

1. I removed the bell housing (I think that's where the leak was coming from... or the pan... hard to tell). The paper gasket got destroyed. Can I use ultra copper gasket maker to reform a gasket? I find those paper gasket are so thin and didn't feel like waiting a week to get a new one. Same goes for the transmission pan gasket. Haven't taken it off yet but I probably will have to.

2. What's spline grease exactly? I know only to use a small amount but can't feel to find that at my parts store.
A few answers for you:
1. I'm not positive which paper gasket you are referring to. Do you mean the one between the bellhousing and the main "box" of the transmission? Yes, you probably could use gasket maker although it's not ideal. You could probably call one of the usual Fiat vendors and have them rush you a gasket, or get a whole gasket set for $30 or whatever. If it were me, I'd get a new gasket. I would not suggest using gasket maker on the lower transmission oil pan.

2. I just use a very light coat of wheel bearing grease. Nothing special. Just don't use too much as already mentioned.

-Bryan
davidbruce
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Your car is a: 1980 Spider 2000

Re: Testing rebuild transmission

Post by davidbruce »

Hi Richard, I agree with Bryan. Any heavy bodied grease will probably be fine. As far as the gaskets go I would be inclined to go to your local auto parts store and buy a roll/sheet of gasket paper of the appropriate thickness's and make your own.Tracing out using the pan and bellhouse as patterns. If you are careful with a pair of scissors or sharp knife the profile shouldn't be too difficult to replicate. An appropriate size belt punch is the way to do nice bolt holes but I have made do with a sharpened piece of pipe or tubing on a piece of wood. I was taught to make gaskets by laying the paper on the housing and using a small ball pein hammer along the edges to cut through the paper. I wouldn't do it on an aluminum housing only steel or iron and not on a threaded hole for fear of damaging the leading edge of the thread. You could probably go the next size thicker on the bellhousing gasket without issues. I like Gascacinch for paper gaskets. Just make sure if you use it or any other gasket cement with the brush in the can that everything is clean. Otherwise you can contaminate the glue and render it useless.
Dave Kelly
Campbell River B.C.
1973 Sport(sold)
1980 Spider 2000(project, aren't they all)
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rjkoop
Posts: 976
Joined: Thu Nov 08, 2012 6:45 am
Your car is a: 1981 Fiat Spider
Location: Ottawa, Ontario, Canada

Re: Testing rebuild transmission

Post by rjkoop »

Makes sense. Thanks.

Clutch back in.

Used Ultra Copper on the bellhousing to main transmission housing. I left the transmission pan on and noticed the bolts were a bit loose. From what I've read it seems like the torque should be 48 in/lbs. So I tighten then up to that.

Going to fill with transmission fluid and let it sit for a few days to ensure no leaks not installed in the car.

Also I'm going to use the new clutch engagement bearing (the one that slides on the yoke/input shaft). I used the old one because it seemed fine and more sturdy.

Richard
davidbruce
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Your car is a: 1980 Spider 2000

Re: Testing rebuild transmission

Post by davidbruce »

Richard, i'm with you. So much of what is available seems inferior to the original. That being said the new one will probably outlast us both. Glad you got it back together. One thing to remember is that some oil leaks won't show up until the oil is hot and thins out. Hopefully you will be ok as the tranny shouldn't get that hot and 90 wt should be easier to contain than thinner engine oil. Let us know how you make out.
Dave Kelly
Campbell River B.C.
1973 Sport(sold)
1980 Spider 2000(project, aren't they all)
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rjkoop
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Joined: Thu Nov 08, 2012 6:45 am
Your car is a: 1981 Fiat Spider
Location: Ottawa, Ontario, Canada

Re: Testing rebuild transmission

Post by rjkoop »

Leaks resolved. It was between the bellhousing and the main transmission case. Removed bell housing, used Ultra Copper gasket maker. No leaks from transmission pan so didn't have to touch that. Filled with correct fluid, let it sit for a few days (at different angles just in case) with baby powder applied to find any leaks, no leaks and installed new clutch bearing (?) with minimal grease. I'll be installing in the next few days.

Thanks for the help and encouragement.

Here's hoping! :D

Richard
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rjkoop
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Your car is a: 1981 Fiat Spider
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Re: Testing rebuild transmission

Post by rjkoop »

Transmission in. Bottom 2 bolts from bellhousing to engine are good. For the top 2 bellhousing to engine bolts there are 2 brackets that slide in with the bolts and they are different. One is wider than the other. Does anyone know which one goes in which side. And I assume they face upwards and angle away from the engine towards the bellhousing? Not sure anymore.

Or a picture would be awesome! :D

Richard
18Fiatsandcounting
Posts: 3799
Joined: Fri Mar 15, 2019 11:23 pm
Your car is a: 1969 and 1971 124 spiders
Location: San Francisco Bay Area

Re: Testing rebuild transmission

Post by 18Fiatsandcounting »

My earlier spiders don't have these brackets, but could they be the engine/transmission hoisting tabs used during assembly or when you want to pull the engine and transmission out through the top? If so, it may not matter which is which, unless they only fit on one side of the bellhousing or the other.

I believe earlier spiders were built by lowering the body onto the engine / transmission / drivetrain which was already connected to the crossmember, and then that was bolted to the body. I'm not sure about later models as they seemed to have these engine hoisting tabs on various locations.

-Bryan
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rjkoop
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Your car is a: 1981 Fiat Spider
Location: Ottawa, Ontario, Canada

Re: Testing rebuild transmission

Post by rjkoop »

Yep. I'm tempted to just replace them with a thick washer. No need for them on my car.

Richard
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rjkoop
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Re: Testing rebuild transmission

Post by rjkoop »

Transmission reinstalled (much easier this time!) and ready for testing...

Image

Richard
Nut124
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Joined: Wed Oct 25, 2017 6:39 pm
Your car is a: 1978 124 Spider 1800

Re: Testing rebuild transmission

Post by Nut124 »

Richard, good luck. The folks here are right, releasing the clutch w 1" of total pedal travel was way off. You need 1-2" of free travel of the pedal. After that the pedal starts to compress the clutch pressure spring. Car should start rolling before the pedal is all the way down if parked in a hill held in place by the clutch, gear.

When running the rear on the blocks, it will likely make some strange clatter noises. This is because there is no resistance and the the slack in gears and joints rattles.
DieselSpider
Posts: 2130
Joined: Wed Dec 24, 2014 10:21 pm
Your car is a: 1978 124 Spider with Isuzu Turbo Diesel

Re: Testing rebuild transmission

Post by DieselSpider »

Nut124 wrote:Richard, good luck. The folks here are right, releasing the clutch w 1" of total pedal travel was way off. You need 1-2" of free travel of the pedal. After that the pedal starts to compress the clutch pressure spring. Car should start rolling before the pedal is all the way down if parked in a hill held in place by the clutch, gear.

When running the rear on the blocks, it will likely make some strange clatter noises. This is because there is no resistance and the the slack in gears and joints rattles.
Running unloaded the spider gears on many differentials can make quite a bit of strange clattering noises.
18Fiatsandcounting
Posts: 3799
Joined: Fri Mar 15, 2019 11:23 pm
Your car is a: 1969 and 1971 124 spiders
Location: San Francisco Bay Area

Re: Testing rebuild transmission

Post by 18Fiatsandcounting »

DieselSpider wrote:Running unloaded the spider gears on many differentials can make quite a bit of strange clattering noises.
Very true. Just last week I replaced the rear wheel bearings in my '69, and I was spinning the axle shafts and driveshaft around by hand, and hearing all sorts of odd noises. For some reason, turning the driveshaft by hand was relatively quiet, but turning either of the rear wheel hub flanges resulted in more clatter, especially when reversing direction. But, when back on the road and driving it, all was well.

-Bryan
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rjkoop
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Your car is a: 1981 Fiat Spider
Location: Ottawa, Ontario, Canada

Re: Testing rebuild transmission

Post by rjkoop »

Thanks for the info. I'll keep that in mind. Just hope there's no smoke from the clutch now that I've ensured minimal grease in the area and the clutch is adjusted correctly. That's what I love about working on cars... Always learning... :D

Richard
SteinOnkel
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Joined: Tue Feb 19, 2019 9:31 pm
Your car is a: 1978 124 Spider 1800

Re: Testing rebuild transmission

Post by SteinOnkel »

rjkoop wrote:Thanks for the info. I'll keep that in mind. Just hope there's no smoke from the clutch now that I've ensured minimal grease in the area and the clutch is adjusted correctly. That's what I love about working on cars... Always learning... :D

Richard
Speaking of smoking clutches. A friend of mine in high school decided it was a good idea to top off the oil on her engine. Which is a perfectly reasonable thing to do. However, on older VWs the transmission has a plug in the top of the bell housing. It allows you to inspect the clutch, flywheel etc and on some models houses timing marks too. She erroneously dumped not one, but two liters of oil in it. Again, perfectly reasonable because the first liter didn't make a lick of difference on the dipstick...

One of the stranger phone calls I've received. "Hey, I topped off my oil now my car won't move" is not something you hear every day.

Sometimes learning can be expensive...
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