Mazda Rotary Club

Cars by Model Type => 2nd generation RX-7's => Topic started by: Thud on August 11, 2005, 10:27:58 AM

Title: OH NO - it\'s MOT day.......
Post by: Thud on August 11, 2005, 10:27:58 AM
I dropped the RX7 of this morning for it\'s MOT and I have to say I\'m BRICKING myself. With a 15 year old car you can never be too sure what surprises your are going to get during an MOT.

My main worries are :
- the car is pulling to the left and has scrubbed the outside shoulder of one of the tyres (not sure if it is enough to fail)
- I recently replaced the two front brake calipers as one of the original ones was starting to sieze. I guess I am about to find out how good my DIY skills are  ;)
- I THINK I have cut out and killed all the rust in the car, but when a mechanic gets all pokey with a screwdriver who knows what other rusty horrors he may find
- The exhaust seems a louder than I remember and my Y piece looks a bit nasty. I suspect it may be blowing a bit.

This is a good garage who I have used in the past with no complaints. I\'m sure they will call me before failing the car to agree on any work that needs done. Regardless, I have a strong feeling that by the end of today my wallet is in for an extreme kicking.

Just thought I would share my anxiety as I know all my fellow RX7 bretheren go through the same trauma once a year.

Hey ho - I will keep you updated on what happens throughout the day.

Stuart
Title: OH NO - it\'s MOT day.......
Post by: grinder on August 11, 2005, 10:32:59 AM
mine pulls to the left aswell - you will have to let me know if you fix it :)
Title: OH NO - it\'s MOT day.......
Post by: Thud on August 11, 2005, 10:44:18 AM
Stu - this problem has been bugging me for months. So far I can\'t tell you what causes the problem but by expensive elimination I can tell you what doesn\'t cause it :
- springs and shocks have been replaced
- front bearings retightened
- tyres rotated and pressure has been checked.
- alignment has been checked

None of these things sorted it so it is probably one of the following :
- tie rod ends shot
- ball joint worn (God no - to replace these on an S5 FC you need to buy a whole new lower arm ££££)
- the car has been crash damaged and not repaired properly
- DTSS bushing shot

I have noticed a weird thing though - the rear driver side sits 1.5" lower than the passenger side rear. I figured this was due to sagging springs, even after I changed the shocks/springs the height difference is still there. Apparenly this is not unusal in an FC and can be due to a lifetime of single lardes sitting in the driver seat. Over time all the bushing etc get tired under constant pressure from a fat bum and the car start to sit unevenly.

Anyway - I will let you know if I ever pin it down and get it fixed.
Title: OH NO - it\'s MOT day.......
Post by: Brett on August 11, 2005, 11:03:23 AM
Is it pulling under braking or during normal driving? If its under braking there\'s a chance its the road camber (assuming your roads are as nasty as the back roads I use) pulling you as you brake.
Title: OH NO - it\'s MOT day.......
Post by: Thud on August 11, 2005, 11:14:02 AM
The pulling is during normal driving and I also hoped it was due to road camber. I tested this theory out on a flat car park and the car still pulled. That coupled with the fact that the car is scrubbing tyres suggests that somethings stinks about my steering/suspension.
Title: OH NO - it\'s MOT day.......
Post by: grinder on August 11, 2005, 11:57:46 AM
why does this sound expensive :(

- springs and shocks have been replaced
- front bearings retightened
- tyres rotated and pressure has been checked.
- alignment has been checked

i have done all them apart from the shocks :(

and it still does it - when i let go of the wheel - its like it turns 1/4 of an inch to the left then it pulls

im wondering if the steeering wheel isnt on straight - if i hold it in a straight line - it drifts to the right - but the laser tracking showed it as perfect ??

dunno - its confused the hell out of me for nearly 2 yrs now !
Title: OH NO - it\'s MOT day.......
Post by: Brett on August 11, 2005, 12:12:06 PM
Out of interest, have you tried calling an Rx7 friendly Mazda garage/specialist? This could be a fairly common problem and they may give you the answer straight out.
Title: OH NO - it\'s MOT day.......
Post by: WillRayden on August 11, 2005, 01:20:19 PM
Quote from: grinderim wondering if the steeering wheel isnt on straight - if i hold it in a straight line - it drifts to the right - but the laser tracking showed it as perfect ??

dunno - its confused the hell out of me for nearly 2 yrs now !

Mine does this as well...  I assumed it was tracking and have it booked in next week to get new boots fitted (Goodyear Eagle F1) and get the tracking done.

I take it this probably won\'t solve the problem then?
Title: OH NO - it\'s MOT day.......
Post by: Brett on August 11, 2005, 05:02:28 PM
Any news? Did it pass?
Title: OH NO - it\'s MOT day.......
Post by: scramp on August 11, 2005, 05:05:48 PM
hmmm, mine pulls to the left as well, i just put it down to old age :) lol
Title: OH NO - it\'s MOT day.......
Post by: Thud on August 11, 2005, 07:54:29 PM
OH MY GOD - it passed!!! In fact it flew through with nothing needing to be done! I am shocked but ecstatic - I plan to Gumball this car to Le Mans next year and this MOT will get me though to the other side of the trip.

I guess the guy in the garage must have had a good time last night or something. That or forgot his glasses. I did however get advised that there was some rust on my sills and floorpan (another winter of rust removal - here we go again...).

On the whole pulling left thing, they garage could not find the cause either. They checked for any play in the steering system but came up blank. They only thing they could suggest was previous accident damage - hope not. For the other guys with cars who pull left - are you also getting uneven tyre wear in your front left wheel?
Title: OH NO - it\'s MOT day.......
Post by: grinder on August 11, 2005, 08:19:22 PM
looks like it yeah - and my Mr MOT man couldnt find why mine pulled either ??
Title: OH NO - it\'s MOT day.......
Post by: Brett on August 11, 2005, 08:39:52 PM
Well done on the pass mate :)  
(Oh the joys of FC ownership, the MOT is like waiting for an operation to end!)
Title: OH NO - it\'s MOT day.......
Post by: FD3SNuttah on August 11, 2005, 10:35:33 PM
haha well done, cos you didnt jinx it you passed! i reckon that your A arm might be bent a little?
Title: OH NO - it\'s MOT day.......
Post by: Martiny on August 12, 2005, 10:35:09 AM
The pulling, I am sure is caused by a front brake caliper sticking. Its a common problem on the FC.

Let the brakes cool completely, or even better, take a drive first thing in the morning. Do a short drive, say about a mile WITHOUT using the foot brakes at all. Now stop the car and go and feel each front brake disc. I am pretty sure you will find one side hotter than the other. The hot side has a sticking caliper and it probably needs to be rebuilt.
Title: OH NO - it\'s MOT day.......
Post by: Thud on August 12, 2005, 11:21:04 AM
ahh - forgot to mention - I also rebuilt my front calipers last month as I thought this may be the cause of the problem. The dust boots on a few of the pistons had disintegrated completly but the pistons still moved. So in my case the problem is not related to the caliper.

It looks as if this is a problem for several members here so I am willing to really look into this further and get back to the board with any answers I find.
Title: OH NO - it\'s MOT day.......
Post by: Grizzly on August 12, 2005, 06:05:22 PM
Well i can tell you this much, I had a problem with my Tryes but with the suspension not being level you will not have proper Weight distrubution. I have Coil overs fitted to my car and i noticed if i dont get them set correctly (one is lower or higher than the others it feels weired to drive), But saying that now i have it set correctly (flat) and good tyres it drives spot on if not a little hard o and it does like to follow the roads Camber a bit (but thats just how i\'ve got it set up).