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How to Change Rod Change Housing Bushings


Full credit goes to Norm Kerr for this handy rebuild trick!

Here is a simple way that I have found to re-bush a Rod type shift housing:

The bushings tend to wear over time, causing the shifting to get even more sloppy than it normally is, and since they are thin walled and not available through normal sources, the typical repair to remedy a heavily worn rod change has been to purchase a brand new housing assy for $145 from Minimania.

If the only thing wrong with your rod change housing is worn bushes, here is a quick, cheap solution that has worked for me:

Buy ” sintered bronze bushings from your local hardware store (these are very standard items sold in the fastener aisle of any decent hardware store). Most carry a thick walled and thin walled version, for this project you want to use the thin walled one, which is approximately 5/8” OD. These are, if I recall, about 1” long, which is longer than we need but seem to work just fine. They usually cost less than $2 each.

I say these hardware store bushings are “approximately 5/8” OD, because that is exactly right. It is a few thousandths larger than that, which is just what you want for a press-fit bushing.

Buy a 5/8” drill bit (to use one of these large bits you will need a ” drive drill, if you do not have a large sized drill with a ” chuck, you can rent one cheaply to do this). Clamp your old shift housing securely in a vise and drill out the old bushing with your 5/8” bit. The old bushing will act as a ‘pilot’ and with a bit of care you will get a clean, new hole in the aluminum housing centered right on the centerline of the old hole.

Press in the new ” bushings, being sure not to press them in too far (you can have extra bushing length sticking outside of your housing, but to avoid fouling the shift mechanism the bushing should not extend inside beyond the surface of the inside wall).

You now have a rod shift housing as good as new!

If your shift rod is also very worn you may wish to replace that with a new one from Minimania ($37 each), part number 22G1930.

Norm Kerr

Disclaimer: I have not got my mini back on the road yet so this repair is still not completely proven. If this causes my car to blow up or something like better gas mileage or faster cornering I'll let you know! ":o)

 

Update for everyone:

After pressing in the bushings you will need to size them and line-bore them with the little aluminum yoke that the shift lever engages. If you don't they may be sticky and cause rough shifting.

A machine shop can do this very excellently, but you can do it well enough like this:

Size the bushings: tape some emery cloth to a 1/4"drill bit (or similar) and use this as a reem to slightly increase the ID until your shift rod slips smoothly through its entire travel. You will have to experiment with how much emery cloth works best, but I found that about 4~5" strip (1/2" wide) was enough to get some 'pressure' against the walls of the bushing. Don't do too much or you'll be back where you started, just enough so the rod moves smoothly.

Line bore: install the yoke on one rod, and run a 1/2" drill bit through the bushing on the other side of the housing and into the corresponding hole on that side of the yoke. Repeat for the other side. Now the holes are all pretty much in line.

Assemble everything and make sure it moves smoothly in all directions (any sticking will cause rough shifting later).

To save more money, you can skip replacing the shift rod by just swapping ends. The OD of your shift rod may be quite worn down where it fit into your shift housing, but that won't matter where it hooks into the transmission. Note that if you do buy a new rod the zinc chromate plating will be rough and should be polished first with a scotchbrite pad before assembly to your newly sized bushing!

Warning: I bought a new shift rod from our Minimania and found out the hard way that it was made 3/8" too short (arrrgghh) and ended up using my old one and its just fine. So, when you buy new parts, always check them carefully BEFORE spending the afternoon assemblying them!

I installed my new KAD shifter after doing the above work and it is smooth, super precise and feels like the bolt action on a well made rifle. Can't wait to get it on the road to feel it in action, based on the "garage test" last night.

Norm

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Another Update:

After living with the result of my work for a while, I have found that my linkage is sticky when hot (the exhaust goes by there), so I think some mention should be made of a few more things to prevent this:

1) soak the bronze bushings in oil before assy (I installed mine dry, which may have been a mistake)

2) the fit between the rods and the bushings should be a little slack ( I made mine too snug, almost a sliding fit, which feels GREAT in the garage, but gets sticky under real world use)

3)  pack the housing with grease (I only lubed the surfaces of the rods themselves).  Position this extra grease above the rods so that it will tend to fall down onto them over time.  The reservoir of extra grease
provides more lube by gravity over time as the rods get wiped dry by the shifting action and dirt/water slowly make their way into the housing.


Someone else posted to close the drain hole and fill the housing with oil, which might work, but I wonder how well the box can work to keep out water over time (may require periodic oil changes?).  By the time the bushings are loose enough to prevent sticking then they can let out the oil, and let in dust/water because there's no provision for a seal on the front.

I put an O ring on the front rod to help divert some dust/water from that
area.

 

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