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Nickel
Nick LaRaia

(6 posts)

Registered:
05/21/2023 03:02PM

Main British Car:


Pilot bushing too tight?
Posted by: Nickel
Date: May 21, 2023 03:24PM

Hello,
New to this forum, looks like a great one.
Been searching for anyone's experience with this. I have a 1980 Buick V6 in a 1980 TR7 with a T5 transmission. Conversion was done 28 years ago, but not many miles on it. Just installed a new clutch and pilot bushing and now cannot get the transmission seated in flush to the bell housing. Is is possible the pilot bushing is now too tight? I slipped it on the input shaft before installing it in the crankshaft to check the fit, it was OK. But it took quite a bit of force and pounding to get the bushing into the crankshaft; now wondering if the compression could be causing an interference fit with the input shaft spindle. Anyone ever had this problem with the T5??
Thanks ahead of time for any help.

Nick


turbodave
dave cox

(183 posts)

Registered:
04/30/2018 03:00PM

Main British Car:
SD1

Re: Pilot bushing too tight?
Posted by: turbodave
Date: May 21, 2023 09:46PM

Are you sure the clutch is aligned? You could remove it and re-try to be sure...

It is pretty easy to pull the T5 input; and gives you an excuse to check and re-shim the mainshaft. May be worthy of consideration?

Alternatively, what T5 is it? If mustang, I have an input i can give you for the cost of postage.


Nickel
Nick LaRaia

(6 posts)

Registered:
05/21/2023 03:02PM

Main British Car:


Re: Pilot bushing too tight?
Posted by: Nickel
Date: May 21, 2023 11:16PM

Not quite sure how this forum works. Replying to turbodave but did not want to reply with a private message:

yes, clutch is aligned, I can get the trans in to within about 7/16" from mating flush to the bell housing. Alignment tool goes in and out quite easily. But measuring the spindle on the plastic alignment tool I get 0.590", the input shaft on the transmission measure 0.593" Not a big difference, but...
This T5 was from a Camaro, so input shaft is different from the Mustang's. But I really appreciate the generous offer of the inout shaft!!


turbodave
dave cox

(183 posts)

Registered:
04/30/2018 03:00PM

Main British Car:
SD1

Re: Pilot bushing too tight?
Posted by: turbodave
Date: May 22, 2023 07:29AM

Clearly something relating to the input itself then...

I'd still remove the clutch and try again, just to be sure.

It really is pretty easy to remove the T5 input. If you look on YouTube for "T5 ultimate rebuild" from "Eric the car guy" he has a good video (two actually) on the full T5 dissassembly and re-assembly. If you have anything more than .040 of up/down/side-to-side play at the tip of your input, it would benefit from a re-shim anyway. You also may want to put a new seal on the input as well.

The input is the first part to be removed, and the last part to be re-assembled. So long as you do it verticaly, you won;t lose the needle rollers.


MGBV8
Carl Floyd
Kingsport, TN
(4517 posts)

Registered:
10/23/2007 11:32PM

Main British Car:
1979 MGB Buick 215

authors avatar
Re: Pilot bushing too tight?
Posted by: MGBV8
Date: May 22, 2023 09:40AM

"But measuring the spindle on the plastic alignment tool I get 0.590", the input shaft on the transmission measure 0.593" Not a big difference, but..."

What is the measurement of the pilot bushing bore?


Nickel
Nick LaRaia

(6 posts)

Registered:
05/21/2023 03:02PM

Main British Car:


Re: Pilot bushing too tight?
Posted by: Nickel
Date: May 22, 2023 10:59AM

"What is the measurement of the pilot bushing bore?"
Yes, good question. Cannot measure it right now. Have to remove the bell housing which means removing one of the headers to pull it out, then remove the clutch so I can get to the bushing. That's next, but I am very busy this week.
I can and will measure the play of the input shaft this evening or tomorrow evening. Will reshim if needed.


turbodave
dave cox

(183 posts)

Registered:
04/30/2018 03:00PM

Main British Car:
SD1

Re: Pilot bushing too tight?
Posted by: turbodave
Date: May 23, 2023 01:40PM

How about purchasing one of these - if you don't want to pull the input shaft.

[www.mcmaster.com]



BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(6470 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: Pilot bushing too tight?
Posted by: BlownMGB-V8
Date: May 23, 2023 02:42PM

Of course there is always something like this:

[www.mcmaster.com]

And if that's too rich another option might be this:

[www.google.com]

Jim


DiDueColpi
Fred Key
West coast - Canada
(1367 posts)

Registered:
05/14/2010 03:06AM

Main British Car:
I really thought that I'd be an action figure by now!

authors avatar
Re: Pilot bushing too tight?
Posted by: DiDueColpi
Date: May 23, 2023 02:44PM

Is the bushing all the way in?
The bearing surface of the pilot on the inputshaft is longer than 7/16 so that suggests that the shaft has started into the bushing.
You can do some measuring or just put a small Oring on the input and see how far it gets pushed onto the input.
Cheers
Fred


Nickel
Nick LaRaia

(6 posts)

Registered:
05/21/2023 03:02PM

Main British Car:


Re: Pilot bushing too tight?
Posted by: Nickel
Date: May 23, 2023 10:33PM

Great to have all this input and all the suggestions! Thank you all.
First, Dave I did measure the play on the input shaft, I really thought you were on to something there, but it is very minimal. I measured .005-.006 with a dial indicator, which surprised the heck out of me given the age of the thing.
I would order one of those plastic go-no-go guages, but they're only 2" long, so I won't be abe to check it until I get the bell housing and clutch out again and at that point I can measure the bore in the bushing.
And Jim, I was looking at the drill bits and reamer, and will likely order one because at this point I believe the bushing will need reaming out.
Fred I was thinking the same as you were about the input shaft having started in, but I took some measurements of the depth from the mounting face of the bell housing to the face of the bushing and then from the mounting face of the transmission to the end of the input shaft. There is in fact 7/16 difference, and inspecting the markings on the input shaft spindle it looks like it was originally only into the bushing by that much, so it appears it is stopping right at the bushing.
Well, this weekend I will be taking the right side header, bell housing and cluch out, measuring and probably reaming that bushing out.
Will let you know what I find!
Thanks again,
Nick


MGBV8
Carl Floyd
Kingsport, TN
(4517 posts)

Registered:
10/23/2007 11:32PM

Main British Car:
1979 MGB Buick 215

authors avatar
Re: Pilot bushing too tight?
Posted by: MGBV8
Date: May 24, 2023 09:16PM

I would source a different bushing or two before buying that reamer bit.


Nickel
Nick LaRaia

(6 posts)

Registered:
05/21/2023 03:02PM

Main British Car:


Re: Pilot bushing too tight?
Posted by: Nickel
Date: May 28, 2023 08:47PM

Ahh, success. Bushing was too tight. Can't fathom why a part that has critical dimensions could be off enough to cause interference, but all's well that ends well. I reamed the bushing out a few thousandths (much less work than pulling that bushing out and installing another), and put everything back together. The input shaft slid right in. I did make sure of that before installing the clutch and bell housing this time though.
Still wondering, has happened to anyone else?
Thanks again for all the responses and advice!
Nick


turbodave
dave cox

(183 posts)

Registered:
04/30/2018 03:00PM

Main British Car:
SD1

Re: Pilot bushing too tight?
Posted by: turbodave
Date: May 31, 2023 01:10PM

So oilite does crush a lot compared to other materials when pressed into a bore, so if you made the part with the ID perfectly to size (maybe 1-2 thou clearance) this would not be enough when pressed (hammered?) into the crank tail.

I made my last bush with 5 thou clearance on the lathe, and 1 thou interference on OD, and it pressed in nicely and closed up almost perfectly.


Nickel
Nick LaRaia

(6 posts)

Registered:
05/21/2023 03:02PM

Main British Car:


Re: Pilot bushing too tight?
Posted by: Nickel
Date: June 01, 2023 06:48PM

Good to know Dave. Funny thing is I had 2 new bushings to choose from sitting on my workbench. The one I didn't pick may have been fine. Just a lot of extra work and frustration.


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