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Re: transmission lockup

To: Max Heim <mvheim@studiolimage.com>
Subject: Re: transmission lockup
From: James Nazarian Jr <James.Nazarian@Colorado.EDU>
Date: Sun, 7 May 2000 02:45:38 -0600 (MDT)
it may be a dumb suggestion, but my dad once rebuilt an A and the engine
was so tight you couldn't move the car at all when pushing, we ended up
dragging it around in 4th behind our van.

James Nazarian
'71 B roadster
'71 BGT rust free and burnt orange
'63 Buick 215 

On Sat, 6 May 2000, Max Heim wrote:

> Well, if you don't have power to the OD unit, it shouldn't be engaged at 
> all. The 3rd/4th gear lockout switch cuts power to the OD when you shift 
> out of 3rd or 4th, so it would have no effect with power cut off to the 
> OD in general. So you may well want to jumper power to the OD just to see 
> if the solenoid activates, and possibly if the lockout switch is really 
> working (I would have bench tested this before installation in the car, 
> since it is pretty much inaccessible. It also may have required some 
> small adjustment via shim washers).
> 
> But the real issue is why is the transmission "locked up"? And what 
> exactly do you mean by "locked up"? I assume you mean that in any gear 
> (1-4), you can't push the car and make the engine turn over (as you tried 
> to do in order to adjust the valves). Are you sure the parking brake was 
> released? Did you try it with the transmission in neutral? You may want 
> to raise the rear wheels off the ground and try turning the engine over 
> with a wrench on the crackshaft pulley nut (remove spark plugs to relieve 
> compression first).
> 
> I don't know of anything the OD could do that would cause this symptom. 
> Whether the OD is engaged or not, the transmission would still turn 
> freely, albeit at a different ratio. The only thing I can think of is the 
> plunger for the pump which pressurizes the hydraulics in the OD. It runs 
> off a cam on the main shaft. If it were improperly installed or jammed 
> somehow, it could conceivably prevent the shaft from rotating. This would 
> necessitate removing the OD unit from the transmission to confirm and/or 
> repair.
> 
> Before you despair about removing the entire engine/transmission unit 
> again, I have found that it is possible to pull the OD off the back of 
> the transmission from underneath the car. You do have to go through every 
> step of engine removal up to to the point you start hoisting it on a 
> chain. But instead of using an engine hoist, you jack it up from below 
> with a floor jack, positioned so that it can roll forward as it lifts. 
> Another floor jack beneath the transmission is also helpful. Basically, 
> the idea is to lift and inch forward the engine and transmission until 
> the tailshaft clears the rear (permanent) crossmember. Then you lower the 
> rear of the transmission enough to pull the OD out and down. The 
> advantage compared to pulling everything is that you don't have to rent a 
> hoist, and you can do it by yourself (slowly and carefully). Remember to 
> drain the transmission oil first so as to limit the flood to a couple of 
> pints.
> 
> If you did not have the OD separated from the transmission previously, 
> you will find out how the pump plunger needs to be manipulated in order 
> to remove the OD unit (it kind of catches on the cam and needs to be 
> depressed against its spring with a thin flat screwdriver inserted into 
> the gap, while you pull back on the OD). Reassembly requires a similar 
> maneuver, and it is the failure of this step that I suspect caused the 
> problem.
> 
> Before jumping to any conclusions, I would consider soliciting the advice 
> of an experienced transmission expert, whether locally or on the list. 
> The advice above is based strictly on my experience, and there may be 
> other, simpler causes and solutions of which I am ignorant.
> 
> I have also experienced a situation with a 4-synchro transmission where 
> the shift lever would lock up, preventing me from changing gears at all. 
> But this does not seem to match your symptoms. Just for the record, it 
> was due to the interlocking arm being misadjusted (or so I recall). 
> 
> Good luck.
> 
> Andrew D. Zimmerman had this to say:
> 
> >This is a multi-part message in MIME format.
> >--------------C49C23F2206F9314F4E2056B
> >
> >All,
> >
> >I am in the final stages of a restoration of a 72 'B.  Engine and body
> >completely overhauled and upgraded.  Only minor work on the tranny
> >though--new o-rings, etc. in o.d. solenoid (and as far as I know,
> >everything went back in the proper position and order).  Put
> >engine/trans. back in car and reinstalled everything, to get ready to
> >try the big crank-up.  My last posting described a problem getting the
> >shifter to move into gears.  That problem was resolved by removing a
> >rather annoying, longish switch for the seatbelt warning system, which
> >was apparently blocking movement of the "remote control" shaft (kinda
> >like removing an appendix--it's there causing all sorts of Hell, does
> >little if anything productive).  Now that the unit shifts beautifully
> >into all gears, I thought I was now ready to check final settings,
> >intall battery fill engine fluids, and crank her up.  Wrong.  Upon
> >putting tranny in 4th gear to "rock" valves open and closed to adjust
> >clearances, I discovered the tranny was locked up.  Same in 3rd; also
> >same in 1st and 2nd.  I suspect the o.d. unit somehow got engaged during
> >work on piston/o-rings, or other movement of tranny outside of the car.
> >
> >The Bentley manual mentions the possibility of a sticking o.d. clutch.
> >Could this lock up motion in all four gears, not just 3d and 4th?  They
> >recommend vigorous blows with a rubber mallet to the brake-ring.  I'm
> >about to try this.  If this doesn't work, does anyone have any other
> >knowledgeable suggestions?  If I hook up a battery, will proper
> >placement of the o.d.  (i.e., wiper/washer) switch cause the unit to
> >disengage?  What else should I try?
> >
> >Thanks for your help!   Andrew Zimmerman
> >
> >--------------C49C23F2206F9314F4E2056B
> > name="a.d.zimmerman.vcf"
> >Content-Description: Card for Andrew D. Zimmerman
> >Content-Disposition: attachment;
> > filename="a.d.zimmerman.vcf"
> >
> >begin:vcard 
> >n:Zimmerman;Andrew D.
> >tel;home:(302) 737-7747
> >tel;work:(302) 888-5293
> >x-mozilla-html:FALSE
> >adr:;;10 Woodshaw Road;Newark;DE;19711-7421;USA
> >version:2.1
> >email;internet:a.d.zimmerman@worldnet.att.net
> >note;quoted-printable:"Freedom is not static but dynamic=3B not a vested 
> >interest, but a prize continually to be won."  (Jacques Ellul, The 
> >Technological Society)
> >fn:Andrew D. Zimmerman, Ph.D
> >end:vcard
> >
> >--------------C49C23F2206F9314F4E2056B--
> >
> >
> 
> 
> --
> 
> Max Heim
> '66 MGB GHN3L76149
> If you're near Mountain View, CA,
> it's the red one with the silver bootlid.
> 


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