sotal Posted October 10, 2009 Posted October 10, 2009 Well I set to my gearbox with a bunch of spanner and sockets and now have a pile of gearbox bits. I think I've got the bit out I need to fix but I have no idea where the bits go or what to call anything! Roughly what I did today was: Remove top cover Remove the PTO bit at the back and the castleated nut behind Remove Bell housing Remove selectors - not easy Remove bits of gears and stuff that look way beyond my experience! Start worrying about fixing it and putting it back together! The problem was that I had no synchro on 3rd and 4th and when draining the oil I found all the synchro detent springs in many bits. So I now need to purchase the detent springs and fit them - but without having the old ones in place I have no idea where they go or how to fit them! Pictures will follow in a minute as I took pictures along the way incase I got stuck! Quote
sotal Posted October 10, 2009 Author Posted October 10, 2009 I believe that the detent springs go on the synchro hub on here (I don't know which bit the synchro hub is) Please treat me as someone who know nothing as it's the first time I've been near a gearbox. Quote
simonb Posted October 10, 2009 Posted October 10, 2009 The 3/4th synchro springs fit between the 2 brass rings on the 3/4th gear and under the centre ring. They are in line with the shaft the gear runs on. There are 3 of them spaced equally around the gear. Its fairly obvious when you get the new ones. I suggest you get a copy of the Series Haynes manual which covers all of this. Quote
sotal Posted October 10, 2009 Author Posted October 10, 2009 Thanks for the reply - I have the haynes manual which I have studying but I'm just feeling a bit overwhelmed! I'm not really sure what half the bits are. Page 68 of the haynes manual shows an exploded view (fig 6.1) of the bits in my photo - but it only shows one detent spring and it's position is vague - is there any more detail anywhere that I've missed? It's all been a huge learning curve so far! Quote
Pat Posted October 11, 2009 Posted October 11, 2009 Thanks for the reply - I have the haynes manual which I have studying but I'm just feeling a bit overwhelmed! I'm not really sure what half the bits are. Page 68 of the haynes manual shows an exploded view (fig 6.1) of the bits in my photo - but it only shows one detent spring and it's position is vague - is there any more detail anywhere that I've missed? It's all been a huge learning curve so far! If its crunching in selecting 4th to 3rd, then the syncro unit is worn out. the springs wont make a difference. Its the syncro itself that will be worn. Its a common thing for these to wear out, you will probably need to replace it . Quote
sotal Posted October 11, 2009 Author Posted October 11, 2009 Is there any way to test the synchro unit on the bench to check for wear? Any idea of price / part number for the parts required to replace? Quote
ejparrott Posted October 11, 2009 Posted October 11, 2009 The bit on the left hand end of the shaft, the two brass rings spaced apart with the steel disc in between, thats where the springs belong, i can see they are missing. Extract that from the shaft and post a photo of the ends of it - could well be thats worn aswell Quote
sotal Posted October 11, 2009 Author Posted October 11, 2009 Thanks EJ, the pictures should be below, 1st three are one end the next 3 are the other: Quote
tuko Posted October 12, 2009 Posted October 12, 2009 In the above pictures, the indent springs are clearly gone. You took clear pictures of the inner splines, but can you take clear pictures of the syncro teeth that are on the outer edge. When the transmission begins to grind when changing up or down its because of wear on the outer teeth of the syncro gear began to wear down to the point that they don't mesh up properly with the gear. Or in other words there is too much slack or free play. Take your third gear and line it up with the syncro gear to see if there is any play, you may have to replace the gear also. Check 4th also. (I've had to replace 3rd on my transmission) Todd. Quote
sotal Posted October 12, 2009 Author Posted October 12, 2009 Hi Todd, thanks for the reply can you dumb it down a bit for me? I'm not quite sure which bits you want me to photograph! Cheers Quote
tuko Posted October 12, 2009 Posted October 12, 2009 OK, here are the teeth that I'm talking about: Quote
tuko Posted October 12, 2009 Posted October 12, 2009 To be honest a series 3 syncro hub costs under 50 quid, I wouldn't put the effort into doing anything with this one, just buy a new one for the piece of mind that it will give you. Todd. Quote
sotal Posted October 12, 2009 Author Posted October 12, 2009 Hi Tuko, Thanks for the image above with arrows on - those teeth look good to me, but I will do as you suggest later and put them up to the third gear to see how they mesh. I'm trying to keep the cost down so would prefer to reuse as many parts as possible, the main purpose of removing the gearbox was to do the rear crank seal on the engine - but I thought I'd quickly do the detent springs whilst the box was out as they were only pence, but now it's spiralling into more and more! It was the comment above by another member that worried me by saying that crunching from 4th to 3rd wouldn't be the detent springs and would be something else - but I can't find anything else on the web to back that statement up and that member hasn't posted back with any further detail Quote
tuko Posted October 12, 2009 Posted October 12, 2009 Yes that's true it can be one of a combination of things that is leading to the crunching in 3rd to 4th. The selector fork can be worn, the teeth on the gears can be worn (if they are rounded at the tops then it's worn, the teeth should be crisp straight edges). The syncro gear can obviously be worn or missing springs and the brass bushing that fit under 3rd can be worn. Even if the distance piece that's found on 2nd gear bushing that comes in contact with the 3rd gear bushing can be worm down and possibly leading to the crunching. Who really knows what exactly is the culprit, but since you have it open it's wise to check everything. You don't want to do this a second time. Todd. Quote
sotal Posted October 12, 2009 Author Posted October 12, 2009 Hi Todd, thanks for the help - I might need more as it comes to testing the other bits you mentioned! Anyway as promised here are more photos of the synchro hub: Quote
Phil Hancock Posted October 12, 2009 Posted October 12, 2009 I would just respring that and give it a try. Use genuine springs tho. Quote
ejparrott Posted October 12, 2009 Posted October 12, 2009 All looks fine to me...I'd go for three new springs in that as it is. What state is the inside of the input shaft synchro teeth? Quote
sotal Posted October 12, 2009 Author Posted October 12, 2009 Here's all the pictures I took tonight, does that show what you needed to know? Or can anyone see any potential problems? http://picasaweb.google.com/celica1.8st/CleanedUpBits?feat=directlink Quote
ejparrott Posted October 13, 2009 Posted October 13, 2009 Your Baulk Rings look fine, which was going to be my next question, so they are nothing to worry about, however your layshaft tail-end bearing looks shot, but i've a feeling you've already asked that as a seperate question. It all looks as shiny as mine, so I'd say get three new springs on the hub and away you go. Quote
sotal Posted October 13, 2009 Author Posted October 13, 2009 My Shopping List currently consists of: Gasket Set 3 x detent clips Bolt in end of layshaft Lock tab washer for rear of main shaft. Primary Pinion Bearing (rumbles a lot) Rear Layshaft Bearing Clutch Release Bearing I still need to pull apart the rest of the box to remove the rear layshaft bearing outer casing so I may find some more bits yet. The only other questionable bit was the roller bearing in the PTO cover bit. It feels smooth if I stick my finger in but there is a little rumble if I spin it on the end of the shaft - it's easy enough to replace at a later date though I guess. So the only question that remains is that a couple of people have mentioned that when their springs went they only had problems from 3rd to 4th but not 4th to 3rd. I have problems both ways, which people have suggested may be something else rather than the detent clips - but I haven't found anything else yet. Quote
tuko Posted October 13, 2009 Posted October 13, 2009 in the image below you'll see what I'm talking about, the teeth on the inner portion of the hub. These wear unevenly from the lose of the indent springs, how unevenly it wears depends on how you dropped the indent springs. Did you drop one at a time?, drop one then two? drop two then one or did you drop all 3 at once? Nobody can answer those questions but the teeth within the syncro hub will wear unevenly and it can be seen in one of your pictures. Pictures of those gears would be helpful. You are getting advice from both sides of the spectrum, you can simply replace the indent springs and be done, or you can do more of a thorough investigation and replace where necessary, it's your decision and your transmission. Good Luck. Todd. Quote
sotal Posted October 13, 2009 Author Posted October 13, 2009 Thanks Todd, well spotted on that gear, I'll look over it for any more, I have seen a very cheap new (old stock) synchro hub and I tempted to buy it but it's make is unknown - do crappy makes like britpart make these or will I be fairly safe? Quote
tuko Posted October 13, 2009 Posted October 13, 2009 Thanks Todd, well spotted on that gear, I'll look over it for any more, I have seen a very cheap new (old stock) synchro hub and I tempted to buy it but it's make is unknown - do crappy makes like britpart make these or will I be fairly safe? I don't believe that Sh!tpart ever made a syncro hub assembly. If somebody can prove otherwise, please do. What you need to know before buying, is what suffix does the syncro hub fit? The later ones don't fit the early ones, they have different part numbers. BTW, what suffix letter is the transmission are we talking about here? Todd. Quote
sotal Posted October 13, 2009 Author Posted October 13, 2009 Yeah I'd noticed that and got the correct part number. It's a suffix D box out of one of the very last Series 3's. Synchro Cluth Assembly Part Number FRC6996 One thing I was worried about was that someone said it has to go in one way, looking at it, it seems perfectly symmetrical and I don't remember which way it came out! Quote
tuko Posted October 13, 2009 Posted October 13, 2009 One thing I was worried about was that someone said it has to go in one way, looking at it, it seems perfectly symmetrical and I don't remember which way it came out! OH, yes it goes in only one way! Look at the splines that fit on the transmission shaft, one is cut deeper. Read the Green Bible, it tells you which way is which. Todd. Quote
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