T90 Problems - Diagnosis??

Is this picture correct??

I sounds like the 2nd / 3rd slider gear is towards the 3rd gear while in neutral and riding on the syncro's.

Does this make sense to anyone?? Or am I way out in left field with this thought??

 

Indeed. You get the different 2nd and 3rd ratios by choosing which gear to lock the mainshaft to. The synchro clutch hub slides, not the gears. In 3rd, you lock the mainshaft to the input shaft. The cluster gear spins but does nothng. In 2nd, you lock 2nd gear to the mainshaft and the power goes from the input shaft gear, through the cluster gear, and to the mainshaft via 2nd gear.

The T-90 has a (sort-of archaic - sorry) sliding 1st-reverse, which can't be made synchromesh. In the T-14 and T-15, 1st and reverse work in a similar manner to 2nd and 3rd on a T-90 - the clutch hub locks the mainshaft to the respective gear. This allows 1st to be synchromesh too.

 

the pic shows that the trans is in 2nd gear
if my eyes are seeing correctly

 

Update...

I started hearing ALOT of tranny noise while in neutral, so I took the shifter plate off again and fished around with a magnet. I found one of the spring plate duhickies whole and one that was broken in two.

The noise was coming from the syncro gear that was spinning out of control. The 4 spring thingies hold the gear in sync with the slider gear, and with the "keyways" gone, it was rattling quite nicely.

I didn't find too much damage to the gears, some have a small chip or groove in them, but in any matter, looks like I will need to drop the tranny and rebuild. This is most likely the cause of the second gear sticking that I was noticing before.... and the clips finally gave up and let loose.

(You can see the groove in the gear in the second pic)

Thank's for your help!

 

What's that green liquid? Eeeyew.

You mean the blocking ring? or the clutch hub, or clutch sleeve was rattling?

Glad you found the problem!

 

Won't be done by thrusday

What I think was rattling, was the skinny gear (part of the syncro I think) that is keyed to the gear by the spring clips that has the slider assy over it. That skinny gear can freely rotate now, where as before it was keyed by the clips.

Forgive me for not knowing the gear names yet, first time in the tranny.

I don't see how to replace the 4 spring clips without dropping the tranny and working from the engine side in.

With the 198 V6 bellhousing, I will need to pull the engine and then drop the tranny... there's no way of getting to the throwout bearing and fork with it attached to the engine.

I think it will take about 8 hours start to finish with a little help, just to replace 4 clips inside the tranny.

Or... does anyone know of a way to replace those clips without dropping the tranny????

 

That green liquid is fresh tranny fluid with about 10 minuites of run time on it. This is why I "flush" this system two times every year. If if gets nasty, I drain and fill, run about a day, drain and fill again. This gets all the nasties out of the nooks and crannies.

 

Yup, those are the spring clips i was referring to before. I had the same problem...but only one of them broke, and then wedged itself so the tranny was stuck in 2nd. Unfortunately you have to drop the tranny to replace those...I don't believe they can be put in without disassembling...at least I couldn't find a way.

 

Thanks...

Looks like I know what I'll be doing next on the jeep

 

Thought about switching tranmissions?

If you had this problem today you might have it again soon.

Something to think about.

http://cgi.ebay.com/ebaymotors/JEEP...oryZ6755QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

 

I do have a T-18 (granny low) with a d20 behind it in the shop. It came out of a '76 CJ-7 with a I6.

I've wanted to put this in... but the input shaft is about 4" too long. I can get a different shaft.. I think. But the one thing that is holding me back is the bellhousing. I have the CJ-7 bellhousing, but it won't mate up to my engine. I have a buick 198, and it has a different pattern than even the 225.

I think that it is time to look at it more closely. I really want the T-18 in that jeep.

hopefully, I can use my d18 and reuse the warn OD with the 4 speed... THAT would be freakin crazy.

Ok... I think that I just about talked myself into it... I'll start to investigate what's needed for the swap tonight.

I believe that there is enough people on the board that has done the swap... hopefully you guys can lend some guidance here and there

 

The '76 T-18 should be a close ratio version (4.01:1 1st) so the short input shaft will have the wrong tooth count. Not much you can do with it but run it like it is or change out all the gears, if I'm right.

 

I think that when I rotated the shaft, I counted around 6 revs engine side to 1 rev output. I will check again with the #'s on the case.

 

To be 100% certain, take the retainer off and count the teeth on the input gear. Nick knows what each should be, and the respective counts are in an old post here somewhere.

 

Actually, you should probably take the shifter top off and count. Not sure, but taking the input gear off may drop needles into case.

 

I spun my T90 first run with the fresh 350 in front of it. Converted to a SM465 with Advance adapter kit. Here is a picture of the difference in trannys. BIG Difference.