Gear selection getting more difficult

samx5 · Postby **samx5** » Fri Sep 23, 2011 11:03 am

I've gradually been getting my car running sweeter by doing all the little things, like gear shift boots, gearbox fluids etc... and until recently the car was driving better than ever, certainly much better than when I bought it. Recently I did a private track day & since then it has gradually lost the smoothness when changing gears. A bit frustrating, since I just had it perfect but anyway......racing.....bloody expensive. Its worse than ever when cold, and 2-3 changes and 4-3 changes are a lot more notchy. When it fully warms up it gets better but is still a bit hit & miss, some changes are like butter and some are notchy and/or obstructive. The gearbox doesn't seem any noisier than before. I'll have a look at the shift boots & the turret again this weekend, but I'm wondering if I've got a dodgy engine mount from exercising the car on the track? I've also noticed that the car has a little bit of vibration when idling that wasn't there before, nothing sinister but noticeable. The tacho needle isn't jumping around so I've been thinking that the engine may be rocking on the mounts a bit more than before. Could it be that the mounts are flexing more & putting the driveline out of alignment just enough to make gear selection more difficult? Does this seen like a reasonable idea worth investigating, and which mounts should I look at first (if anyone has previous experience with these things). Car is a 99 NB8a 5 speed. Thanks all.

Matty · Postby **Matty** » Fri Sep 23, 2011 12:28 pm

Probably the clutch slave.

93_Clubman · Postby **93_Clubman** » Fri Sep 23, 2011 12:41 pm

samx5 wrote:I'll have a look at the shift boots & the turret again this weekend...

If you do the above, check the gear lever collar/ cap which is at the bottom end of the gear lever. OEM is white plastic which wears, however they can be replaced with a brass alternative - usually some for sale on ebay, but a WTB on here might be better first.

samx5 · Postby **samx5** » Fri Sep 23, 2011 1:42 pm

Hmmm, clutch slave oil was replaced only a month or so ago, will check for leaks. The slave cylinder was replaced 12 months ago. Thanks for that.

Paul, do you mean the small plastic cap that goes on the bottom end of the shift ball that can move freely over the metal end of the shifter? Thats the only thing I didn't replace when I last had it apart. The white plastic ring collar that holds the upper shifter boot on is fairly new, as I did both shifter boots only about 3 months ago, but I'll check again just in case something's come away again. Cheers,

Steampunk · Postby **Steampunk** » Fri Sep 23, 2011 4:14 pm

My vote is the engine mounts or the three bolts holding the stick in the housing have come loose.
Does selecting all gears when stationary feel better?
If the bolts have come loose, put either a spring washer on them, or a bit of high-temp threadlocker.

93_Clubman wrote:OEM is white plastic which wears, however they can be replaced with a brass alternative - usually some for sale on ebay, but a WTB on here might be better first.

I wouldn't, the brass ones wear quicker:
http://mx5cartalk.com/forum/viewtopic.php?f=29&t=36436&hilit=beatrush+shift+bush&start=15

93_Clubman · Postby **93_Clubman** » Fri Sep 23, 2011 5:45 pm

samx5 wrote:Paul, do you mean the small plastic cap that goes on the bottom end of the shift ball that can move freely over the metal end of the shifter? Thats the only thing I didn't replace when I last had it apart. The white plastic ring collar that holds the upper shifter boot on is fairly new, as I did both shifter boots only about 3 months ago, but I'll check again just in case something's come away again. Cheers,

Mike, yes, the small plastic cap that goes on the bottom end of the shift ball that can move freely over the metal end of the shifter.

Andrew, recall T & J's issue with the Beatrush brass collar/ cap, but from memory there was an issue with the group buy mentioned as Beatrush mixed 5 & 6 speed bushes together without telling anyone, which explained some fitting poorly as per the link. I recall as I came in on the end of or after the GB, & Sliq mentioned it in PMs. It might also have been a mention in another thread on the subject. Seeing T & J's are the only two that have mentioned an issue it in a decade of forumites using these, I wouldn't be completely put off. Although would try & source them locally, ensuring correct 5 or 6 speed type, given from memory Beatrush's shipping from Japan doubled the price.

Steampunk · Postby **Steampunk** » Fri Sep 23, 2011 7:53 pm

93_Clubman wrote:Andrew, recall T & J's issue with the Beatrush brass collar/ cap, but from memory there was an issue with the group buy mentioned as Beatrush mixed 5 & 6 speed bushes together without telling anyone, which explained some fitting poorly as per the link.

Yeah I think it was Bigdog who pointed out there was a difference, and I was surprised that brass wore out that quickly, regardless of fit.
I guess what I was trying to say is there is nothing wrong with the OEM plastic ones, I just wonder how much Mazda sells them for.

93_Clubman · Postby **93_Clubman** » Sun Sep 25, 2011 12:01 pm

1red5 wrote:Yeah I think it was Bigdog who pointed out there was a difference, and I was surprised that brass wore out that quickly, regardless of fit.
I guess what I was trying to say is there is nothing wrong with the OEM plastic ones, I just wonder how much Mazda sells them for.

Surprising some wore so quickly, but seems the fit &/ or brass grade was the problem:
viewtopic.php?f=44&t=30679&p=422841&hilit=brass+grade#p422841
viewtopic.php?f=44&t=30679&p=419367&hilit=brass+grade#p419367

Reckon the plastic ones are about half the price of the brass ones, excluding shipping if purchased from Japan, when required. However, the brass ones have improved gear changes for some that seem to chew up their plastic ones.

mazdatenfive · Postby **mazdatenfive** » Sun Sep 25, 2011 4:09 pm

If this is what you need, I have one.

Dsc03410.jpg

Postby **Okibi** » Mon Sep 26, 2011 4:25 am

mazdatenfive wrote:If this is what you need, I have one.
Dsc03410.jpg

Or get a metal one, keeps that "as new" shift feel longer than the plastic ones.

samx5 · Postby **samx5** » Thu Oct 06, 2011 6:27 pm

I'm picking up a shifter bush tomorrow, will fit it and see what happens. How easy is it to get the old one off?? I took the console out and the shifter boots off the other night to have a quick look. Both of the boots that I replaced in January are still as new, and all seemed to be bolted down OK. I took the shifter out of the turret & had a quick look at the bush, it looks OK as far as I can see but is a little difficult to drop back inside the turret, like you have to get the angle perfect. The turret is still full of oil but is dirty, so I'll replace that when I do the bush. Anyway, took it for a drive and it felt heaps better, I put the car away thinking whatever I had done had fixed the problem. Next morning I drove off and it was as bad as before!! Weird. I've been leaning towards a clutch problem, as the friction point is a little higher than before. I looked at the slave cylinder and found no leaks or oil in the bubber boot. The clutch fluid is new, it went black pretty quickly but is still full. Engine mounts are also a possibility. When I rev the car in neutral the gearshift moves to the right with the torque of the engine, not sure if they all do this as I've never tried it before. I can also see the engine moving a little at idle. I accept that some movement will occur but not sure what is normal. Once I've replaced the bush I'll see how it goes.

93_Clubman · Postby **93_Clubman** » Fri Oct 07, 2011 12:08 am

samx5 wrote:I'm picking up a shifter bush tomorrow, will fit it and see what happens. How easy is it to get the old one off? ... I took the shifter out of the turret & had a quick look at the bush, it looks OK as far as I can see but is a little difficult to drop back inside the turret, like you have to get the angle perfect. ... Once I've replaced the bush I'll see how it goes.

Easy to get the old bush off - the slightly fiddlely bit is getting the shifter assembly back in as you found. GL!

Silvia · Postby **Silvia** » Sat Nov 19, 2011 12:20 pm

Having a similar snicking problem when changing with gearbox cold...mainly into second but it does get better as it warms up.
Are there detailed instructions on replacing the bottom of the gearstick bush please?

manga_blue · Postby **manga_blue** » Sat Nov 19, 2011 12:31 pm

Everything is shouting engine mounts are stuffed. You would need to get underneath and start prying around at the rubber blocks between the steel plates to see if the rubber is sheared. I'd just replace them anyway with Mazdaspeed mounts. Shift will be crisper and they don't break as soon as you start trackwork.

Forum sponsors MX5Mania and MiataRoadster sell them.

Steampunk · Postby **Steampunk** » Sat Nov 19, 2011 2:56 pm

Silvia wrote:Having a similar snicking problem when changing with gearbox cold...mainly into second but it does get better as it warms up.
Are there detailed instructions on replacing the bottom of the gearstick bush please?

Open-end spanner that just fits on the shaft, smaller than the lower ball diameter, and give it a sharp hit with a hammer.
Do it over something to catch the bush from bouncing around and not damage it, ie. bucket with a towel in it, over the couch etc.