Bad ISB question.

[Crossroads]

I'm fairly sure that the ISB in my '91 Si transmission is shot. There's a grinding/growling sound at idle with the clutch pedal out, just as it shifts into second, fairly loud all the way through third, audible through fourth and fifth, and comes around every now and then in first and second.

My question is, has it gotten to the point that the transmission's shot? If so, approximately how long until the bearing freezes?

I'm thinking I might have to buy another transmission in the near future.

Also, what's the OEM part number for the ISB and the seal I need (I'll be using the posted DIY)? If I buy a new transmission I'm going to go ahead and change them out before I put it on.

[DirtyDC4]

If you have the chance, pull the trans now and replace the parts that are bad, along with putting in new seals. You should be good as new.

(#15 and #21 on this page are ISB and seal) hondaautomotiveparts.com/ (http://www.hondaautomotiveparts.com/auto/jsp/mws/prddisplay.jsp?inputstate=5&catcgry1=CRX&catcgry2=1991&catcgry3=2DR+SI&catcgry4=KA5MT&catcgry5=MT++++++CLUTCH+HOUSING-+DIFFERENTIAL)

I blew up my 4-speed a few years ago (both diff bearings went BLAMO! and ISB was going bad) and I was able to tear it down and rebuild it this past summer. Have had no issues with it.

[Crossroads]

My biggest concern is getting everything apart and my input shaft already being toasted. Would 8-10 hours sound like a fair time estimate for the first time? I built my Z6 into EF swap with OBDI conversion so I'm not a total n00b. I just don't have a lot of experience yet and zero with transmissions. Doesn't look that much more difficult than putting a block together, but I don't know.

I went to both Majestic and SLHonda but the picture is kind of confusing me on what parts to get. I don't want to order something, or buy it for almost twice the price at my local Honda, and have it be the wrong part.

[94z6ex]

http://www.d-series.org/forums/showthread.php?t=14079

ISB removal and install.

as for parts....go to a honda dealer and tell them what you need. i just replaced mine about 6 months ago and i also replaced the seals. When i opened my tranny, i had no idea what the problem was (i could shift into any of the gears....... turned out my isb was toasted) i looked around and found the my ISB exploeded and was missing half of the balls.

i replaced it with a new one and also new seals and it runs great now. Just make sure you read the DIY link very closely because the shift inetcolck guide bolt is very important if you do not remove it and install it in the correct order.

transzex will reply soon im sure and he is basically a tranny god. hopefully he will tell you what your best bet is as far as what you need to do.

also, if its your first time pulling a tranny and taking one apart, i would allow for a least 2 days......lots can go wrong and you definately dont want to rush things. Some would say trannys are harder to work on than an engine some would disagree with that. I know on the main shaft assembly, you have to be careful because there is lots of clearnces that have to be carefully measured after it is taken apart and reassembled....but you shouldnt have to worry about that with an isb fix.

i wouldnt buy a new tranny and replace the one in that...i would just replace the one in your current tranny because at least you know how youve drove your car and you know how well the trannys be taken care of. replace the bearing and seals and youll be set

good luck

[94z6ex]

and after you get everything back together, make sure you run an adequate amount of trans fluid, because low fluid can cause premature isb failure.....i reccommend picking up 2 quarts of honda manual tranny fluid while you are at the dealer buying you parts.

[transzex]

Crossroads, your location would be helpful.......esp. if I'm close.

noise into 3-4-5 is usually BAD..........and when I sad bad, death is close at hand.

[Crossroads]

Well, that doesn't sound good. Death is close, but how great is the chance of my input shaft being toast? I read a post about another user who found a lot of metal behind his throw out bearing and a lot of play in in the IS and you told him the transmission was junk.

I just ordered the parts from Honda and they'll be in on Wednesday. I also read that DIY and did a fair amount of searching before posting. Oh, and I live in Northern California in the Sacramento area. Thanks for all the help guys.

[transzex]

Katie aka Sexirexy (however she spells her username!) lives up that way, maybe she can help.

She replaced her ISB on her own, it's her avatar.

Part numbers you need.......

91216-PL3-005 seal
23927-PL3-000 thrust washer
91002-PS0-003 bearing

Since your on the west coast, I'd use SLHonda.

Have access to a digicam and set up a photobucket account....pics are worth 1000 words......really.

[Crossroads]

Have a digital camera and a Photobucket account. However, if the symptoms say there's more than a 50/50 chance the shaft is toast I really need to buy another transmission. I'm not trying to sound like a "gimme now!" n00b, I just have time frames I have to work in.

This is what I'm up against. My city has fairly strict codes about "dismantled vehicles in public sight" and I don't have a garage so I need to get the work finished as soon after I start as possible. I have a friend with a garage but he doesn't have a computer and his wife has a shitfit when I use the garage for more than a day because then she has to walk out the front door to get into her car...he's also a 30 minute drive from my house. I will definitely post pictures though.

I'm not concerned with pulling the transmission. I know I can do that and I'm fairly confident that I can do the inside work in about three hours longer than what "the book" says it'll take. I take my time the first few times I do something to make sure I'm doing everything correctly. I'm not a professional mechanic by and stretch but I'm nowhere near the typical newbie either. Just a little about me. :)

Holy shit! I just looked up the part numbers and even with a 10% discount I still payed twice what SLHonda has the parts for. Yeah, I am not happy about this.

[Crossroads]

Outstanding. I was able to cancel my order because I put it in after 3pm yesterday.

[Crossroads]

Hmm. Did I make myself seem like an impatient n00b?

Just have time frames I need to work within. I need to know at what point this thing is trash and whether the symptoms say there's a good chance it's already there. Please and thank you.

[s_18]

So, if there is some sound in 1st and 2nd, but the sound is too weak to hear further up,
there's a good chance it's the ISB, just not that bad yet?

A buddy of mine has a tranny making this sound like I described.
So is there any other things it could be, or is it most likely the ISB?

(Sort of thread jacking, but since it's regarding the same problem I hope it's ok)

[Crossroads]

Parts are in. I really need to know if this transmission's worth saving before I pull it. Along with the city's crap this is my DD, so once again I need this taken care of in a timely manner.

The noise hits at around 4k rpm in 1st and 2nd now, has gotten worse in 3rd, and louder in 4th. I'm just looking for the odds here from transmissions you guys have worked on with similar symptoms. I understand that this is the internet and there's only so much you can tell me. But any help would be really cool.

[solo-x]

unfortunately, you won't know for sure until you pull it.

[Crossroads]

Craptacular. I guess I'll just go ahead and find another one. It's totally not worth it to me to pull it, see that it's beyond repair, have to put it back in, and then do the work all over again two weeks later.

[transzex]

why I always have a spare ready to go.

Right now it is a 92-95 CX tranny, but if the cars goes, does it matter?

[Crossroads]

Here's a thought that might save me some scratch. The EF DX transmission is the same as the Si but with a lower final drive, right? How difficult would it be to swap final drives?

[solo-x]

not that difficult at all, at least no more difficult then replacing the ISB. if you've lunched the case, you can put the whole gear cluster/diff/final drive right into the DX case. add fresh bearings and seals, inspect syncro's and forks, assemble and call it a day. one caveat. if your Si box is a big bearing box and the DX is a small bearing box you'll need to put the ring gear on the diff from the box you're using.

[transzex]

and RESHIM!!!!!!!!!!

He's never opened a tranny, a gut swap is NOT a good idea!

[Crossroads]

Heh. Yeah I'll go ahead and save that option for later when I'm more competent. I don't want to get too in over my head with this. :D

[solo-x]

and RESHIM!!!!!!!!!!

He's never opened a tranny, a gut swap is NOT a good idea!

enlighten please, why isn't it a good idea? good point on the reshim, i forgot to put that in.

[green_hornet_96]

It's hard enough replacing the ISB as it is the first time without adding in other work.

Take my car-- I had the tranny done in four hours, but the whole mess took 3 weeks due to issues with motor mounts, both axle nuts seized up, a torn ball joint boot that let dirt destroy its innards, axle seals (recommend replacing if they're old, mine were already leaking and didn't help things), and a bad wheel bearing.

[solo-x]

but if the Si case is fubar'd, and he has a DX case lying around....

[Crossroads]

The case is fine and the transmission shifts smoothly. It's the main shaft I'm concerned about. I just know that people don't put any value on anything DX. So instead of paying $100+ for another Si transmission I could get a DX one for next to nothing and put an Si final drive into it.