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Transmission Rebuild

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As I am in the middle of a tranny, od, and clutch rebuild I had the following questions:

Thanks in advance for the answers

1. If rebuilt correctly, how long or how many miles can a person expect a 1959 BT7 transmission to function correctly barring something unexpected.

2. Can a later model Healey transmission be installed for superior performance and is that worth it.

2. Doe the overdrive use a separate oil reservoir from the transmission fluid? which has synthetic, and I understand synthetic should not be used in the overdrive.

3. Is installing a toyota tranny economical or easily adapted to the healey. I only ask this because I would rather not spend $3,000 every couple of years on rebuilding and have a fragile transmission in the meantime.

Thanks

Will
 
Wil

I would expect a properly maintained transmission to outlast the engine by a factor of two to three. Big Healey transmissions were not known as the weak link in the system. A failed transmission, in my opinion, is usually due to poor maintainance.

Old cars are often neglected, I would guess that the clutch hydraulics failed or the oil in the transmission was allowed to get low sometime in your cars' past life. With bad clutch hydraulics, the transmission will not disengauge from the engine. So the gears grind every time the car is put in first or reverse and the synchros work extra hard to match speeds in the other gears. These actions cause metal bits to be in the trannie oil and places they shouldn't be causing premature failure of the transmission.

No or low oil causes heating and friction and encouraged galling on moving surfaces again with the same premature failure.

The moral of the story is: Now that you have a good one, take care of it and you'll never have to touch that transmission again, even if you put 100k plus on the odometer.

To answer your other question: Yes, they make conversions to put other transmissions in the Healey. I've never used one so I'll let someone else tell both of us whether the conversion is worth the effort. Personally, I think my car would lose some of its charm if it didn't have the overdrive on the dash. On the other hand, if my trannie failed big time tomorrow and the bill was $3200 to repair it, I might think twice about a nice $1200 5 speed conversion.

The transmission and overdrive SHARE oil. Do not put synthetic oil in the gear box. It sounds like a lovely idea, but the over drive will fail shortly after this is done. The overdrive has a clutch that will slip and fail if the new, super slippery, stuff is used.

One other caveat: Be sure the safety cutout turns the over drive off in reverse and the lower two gears as designed. The overdrive was ment to spin in one direction only. If spun in reverse, it will fail. The Healey generates a lot of torque in the lower two gears. The torque could cause the overdrive clutch to slip and fail in the same manner as the slippery oil.

nuff said.

Best of luck
Hope she's running soon.
Thom
 
Thanks for the comments Thom.

I wonder why the Redline synthetic that folks rave about is such a great idea if synthetic oil is bad for the Overdrive.
 
I'm not familar with the Redline product. I use Penzoil or Kendall, because I can find the stuff. Any Redline users out there that can educate us?
 
I've been using Redline MT90 and MTL90 for several years and plenty of other Healey folks are using it. It does not harm the overdrive. The folks at Redline are very familiar with the Laycock De Normanville OD. There is more info on the oil at www.redline.com under the product section.

I found the shifting much smoother(less notchy) going into gear and quieter first gear noise (I have the common worn first gear problem)after switching over. The only negative I've heard is the posibility of increased oil leaks from the trans and OD. I called Redline about this ... they say this shouldn't be a problem because they use seal additives but conceded that if the oil being replaced was thicker then gasket leaks could increase.

Cheers,
John
 
Will,

Regarding your question #2 ...

I checked one of my books (Original Austin-Healey by Clausager) and they have the following production changes regarding the gearbox/clutch:

March '59 - Stronger gears, revised gear and overdrive ratios

Feb '60 - More rigid gears introduced. Plain bushes instead of needle roller bearings to layshaft. Gear ratios revised

Jun '60 - Needle roller bearings re-introduced for gearbox layshaft.

Nov '61 - New gearbox, with top selectors and centre change (as opposed to side change). Ratios unchanged.

May '63 - 9.5" diaphragm spring clutch introduced.

Oct '63 - Longer mainshaft to gearbox, gear ratios revised.

Oct '64 - 9" instead of 9.5" clutch

The two major changes were Feb./March '60 with a major improvement as the entire gear cluster was made more rigid. This occurred on cars with OD from engine number 29D/10897. Then the change from side to top gear lever. (engine number 29E/2246, chassis numbers BT7/15881). The OD did not change significantly over the life of the 6 cylinder cars.

When was your BT7 produced? I think the gearboxes/OD's are interchangable but the longer mainshaft change Oct '63 is a concern. Anybody else have comments on this?

Cheers,
John
 
After the rebuild, how one shifts will have bearing on the longevity of a transmission. Simple things like using the brakes to slow down instead of downshifting will save the synchros. Brakes are a lot cheaper and easier to replace than transmissions.

Of course, since dealing with a transmission without a first gear synchro, one will always want to be at a full stop before shifting into first. I remember when I had my 1961 BT7, I often skipped first gear when I felt I could just to extend the life of the gear. Of course, one doesn't want to lug their engine or wear out a clutch, either.
troll.gif
 
Hello, Will, and all you other Healeyophiles!

I just called Redline Oil and spoke to the on-duty technician. He answered all my questions and sounded as if he were very knowledgeable about the overdrive needs/concerns, etc. His recommendations to me for my BJ8 are:
Engine - Redline 10w30
Tranny w/overdrive - Redline MT90
Differential - Redline 75w90

Redline's free phone line is: 800-624-7958

I am seriously considering changeing over to the Redline product. If anyone has any observations on negative results such as increased leakage, etc., please contact me.

Thanks for posting! Yours, Steve
 
Steve,

As I mentioned before, I did notice some leaking with Redline in the gearbox but it was also leaking with the previous oil. Hopefully a new set of gaskets will fix it.

Most people recommend 20w-50 for the Healey engine. I guess it depends on how fresh and tight the motor is.

For the rear end I am using Schaefer gear lube because the guy who set up the 3.54 rear end swore by it. I couldn't find it locally (they seem to only sell to non-retail, truck supply, maintenance yards, etc.) so he sent me some from Texas. Otherwise I would have tried the Redline stuff.

Cheers,
John

[ 11-21-2002: Message edited by: John Loftus ]</p>
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by stever:


I am seriously considering changeing over to the Redline product. If anyone has any observations on negative results such as increased leakage, etc., please contact me.<hr></blockquote>

I recall there is a guy in Australia who races his Healey, has a web site and swears by RedLine in his transmission. I've seen several people say it makes shifting easier. I can definitely see it in the transmission and differential.

My only thought about using it in the engine is that it should changed relatively frequently (2x per year recommended, which translates into about 1,000 mi or less between changes for the typical Healey), and that gets expensive. A good quality oil should be just fine for 1,000 miles. My opinion is a regular 20W50 for the engine.

cheers.gif

John
 
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