[Top] [All Lists]

Re: Overdrive swap

To: MG List <>
Subject: Re: Overdrive swap
From: Max Heim <>
Date: Sun, 03 Jun 2001 18:36:51 -0700
Think again about the clutch. It's highly probably that you will want to
replace it once you open things up -- might as well have it on hand and not
hold up the show. It's a big BIG pain to go through this whole routine again
a few weeks down the road.

Check the Moss catalog driveshaft listings to make sure you have the correct
one on hand for your new combination. You can just measure the one you have
if you're not sure of its origins.

Did you say your car was originally fitted with OD, or was that someone
else? If so, one might assume the OD wiring harness is already there -- but
you know what they say about "assuming" anything. Better crawl underneath
and look for yellow wires dangling around the tranny somewhere up by the
shifter extension. I don't know where the OD switch was located on a '70 --
was it on the column stalk? If so, you might trace the relevant wires from
the stalk bundle under the dash and see if they are connected to the harness
(consulting the wiring diagram, natch). If you know your car was not
originally fitted with OD, then no, it won't have the wiring.

If you don't have the OD harness extension, don't panic. It's a pretty
straightforward circuit: power -> switch -> 3rd/4th exclusion switch (on
tranny) -> OD solenoid -> ground. I ran it behind the dash and center
console, and down through the tranny filler hole, to get to the
tranny-mounted switch. The wire for the solenoid is probably already on the

The other thing you might want for this swap is the transmission mount
rubber -- it seems as if this item is always a deteriorated mess. And don't
forget the exhaust headpipe donuts -- they always need replacing as well.

I would leave the Weber in place while you sort out the OD situation. You
don't want to create too many variables. Hope this helps. Good luck!

on 6/3/01 4:36 PM, K. Johnson at wrote:

> I've seen a couple of posts, but none of the responses as to what it takes
> to do
> an overdrive swap.  I've got a 70B that I'm swapping the engine and tranny
> out for a different engine and overdrive tranny.  Just what do I need to
> have on hand and what am I gonna want half way into the event???  Should
> the wiring for the overdrive all ready be in my car, if so where the heck
> to I start looking for it???  I  know I should probably put a new clutch in
> while it's out, but I don't think finances or gonna let me do that right
> also has a weber downdraft carb on it, and I know nothing about
> these.  Would it be better to switch back to my SU's or just leave it as
> is, since it was running before that way and then swap them out later if I
> decide I don't want the weber???
> Kathy
> 70B
> PS - Larry Hoy - if the engine in it can make it, I plan on going to
> Glenwood, can I pick your brain about this while I'm there???



Max Heim
'66 MGB GHN3L76149
If you're near Mountain View, CA,
it's the red one with the silver bootlid.

/// mailing list
///  (If they are dupes, this trailer may also catch them.)

<Prev in Thread] Current Thread [Next in Thread>