issue with manual trans after swapping bellhousing

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GoinTopless240
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Car: 1993 Nissan Sil40 Vert & 2008 VW GTI & 2010 Infinity EX35 bought in 2019 (15,000) miles
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Hey everyone,I need a little help. I have a 93 240 Vert w/SR swap and 5 speed conversion. Well the trans that came with the swap crapped out. I found a 5-speed from a 240. I took off both housings to swap the SR housings on (bellhousings are different). Anyway after putting bellhousing on and sealing it up, now the input shaft turns REAL hard. Almost like it's stuck. Any ideas as to why? I put everything back together and tried to move the car and it was like the brakes were on (they weren't cause wheels spin freely). Is is possible to put bellhousing on too tight? any thoughts would be great.


scottydog
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Car: 1992 240sx

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Bell housing bolts on too tight shouldn't do that? The bolts should be 22-29 and 29-36 depending on which bolt.

Are you saying in neutral the car won't roll easily? Sounds like a tranny issue. Does the clutch seem ok? If it rolls with the clutch pushed it's stuck in a gear. If it won't roll with the clutch pushed in then either the clutch isn't working or the input shaft is misaligned/bent and seized up on the pilot bearing.
Modified by scottydog at 10:12 AM 7/22/2008

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GoinTopless240
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i'm gonna pull it again.. clutch is good.. i'm thinking bent input shaft or seized pilot bearing as well.. gonna split the bellhousing again. I've gotta say it's the easier of the two. The tail housing is a pain in the a**. Getting the shifter forks to line up and not getting gasket sealer everywhere is tricky. Bellhousing should be easier.. I'll let ya'all know.

Second Shadow
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you need a different bearing. I had the same problem with my swap, well the SR gear box was screwed when I got the motor, so I used my KA gear box with SR bell housing, and it turns out they do match up but neither bearing would work(this could have something to do with year I suppose). took it to a transmission shop and they found one that fit and gave it back put together and functional for $100.

this was for 93 KA24DE gearbox on S13 blacktop bell housing.

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Hijacker
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'94 F-150
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I'm agreeing it sounds like a bad main gearbox bearing. However, in my experience, the KA and SR have used the same bearing. But knowing Nissan, that's not always the case (like with Second Shadow)

scottydog
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I agree with nissan everything is not always as it seems. For some reason my flywheel was not "standard", as it matched a Stanza part. I had to buy a separate stanza clutch/flywheel, and a 240sx to bearing etc. Not sure if someone swapped them out years ago.

Your problem has to be either to bearing or main tranny bearing.

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GoinTopless240
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Update ... well gang, I pulled the transmission down. I loosened the bolt that tighten the tailhousing and bellhousings. I split apart the bellhousing from the gearset and Viola` the gears turn smooth as butter. Here's the odd part. If I tighten the bolts even just a little the whole assembly starts to bind again. Is it possible to put small shims in between the bellhousing and midsection (giving the bearings a bit more clearance) and just put a thicker gasket sealant on? Any ideas? I think this gearset came from a 95 240 (I have heard this was a bit of a bastard year for some parts). Thanks again for the input earlier.....

Oh yea, background info.. Motor swap and tranny were done 7000 miles ago, so flywheel/clutch and throwout bearing are good/new. What happened was a ballbearing from old trans came loose and wiped out two front gears (the two right behind bearing in bellhousings). They went while gently cruising on highway. The car lost all gears except 4th and still moved easily. Car is a daily and driven gently (no drifting or racing etc..). Motor side was good and still is (no issues). Driveshaft and mid bearing are good (no binding). Problem seems isolated to trans. I will post updates as I can.

scottydog
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Shims and extra sealant sound like a no-no.

I think Second Shadow got it right. You need a different bearing.

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GoinTopless240
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Okay Gang, UPDATE....UPDATEI'm gonna take some pictures tomorrow, but the problem has been solved. It has taken some time, but it was a modification that had to be made to the bellhousing. The SR bellhousing needed to be ground down on the inside where the 1/2nd shift rod travels. Note the outside of the casting, not the area where the rod travels. Apparently the 240 gear set has bigger gears (possibly the 1st gear ?). If you look at the 240 bellhousing where the 1/2 shift rod travels into the bellhousing, you will notice a corner missing (like it was shaved down). When I tightened the SR bellhousing the actual gears were making contact as I tightened it down and bound up the transmission. Ground it down... and POOF, no more binding. Spins and shifts like butter. I think i must have popped off and resealed that housing like 5 times...aaarrrghhh. Anyhow I will post some pics of the 240 bellhousing where the difference is and hopefully help someone else to avoid this headache. Thanks for the input everyone gave. It kept me going and double checking everything. Perserverance paid off....and saved me some money. On a side note - when Hijacker said lining up the shift rods takes a few tries... it does. What a PITA ! Thanks again gang.

Beowulf2actual
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Car: 93 240sx vert with manual swap

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Well, hopefully I dont get flamed for bringing this WAY back from the dead.....Yes, i searched.

Having a similar issue as the OP with my 93 Vert. Followed the tutorial on how to change bellhousings but the issue I am having is that it feels like the transmission is seized. It ll only go into 5th gear (what i think is 5th anyway). When i mated the SR bellhousing up to the KA trans it was a little finicky but they did go together. Am i having a shifter fork issue here? I wasn't sure from this post what exactly needed to be ground down. Any help would be appreciated.

If the OP is still a member, I am also located in charleston.

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GoinTopless240
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Car: 1993 Nissan Sil40 Vert & 2008 VW GTI & 2010 Infinity EX35 bought in 2019 (15,000) miles
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Bringing back from the dead to answer an old thread, but the it a nub that sticks in the outer main gear hits it. It only happens when get everything bolted up tight. Drove me but until a guy at the transmission shop noticed it and grabbed hit grinder and buses a little nub off and every was fixed.. sorry we left Chucktown in 2011 and am looking to start reviving the vert again[youtube][/youtube]


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