Home 
Home Search search Menu menu Not logged in - Login | Register

 Moderated by: Greg Fletcher
New Topic Reply Printer Friendly
Second gear popping out  Rate Topic 
AuthorPost
 Posted: 03-21-2018 09:37 am
  PM Quote Reply
1st Post
stuartmorgan
Member


Joined: 05-07-2013
Location: Melbourne, Australia
Posts: 39
Status: 
Offline
Hi Gang
Stu here again from Windy Melbourne Oz with Tangerine MKII
Ok I've got it all back together, all assembled, looks great and NO Trans oil leaks anymore, BUT
My son and I test drove it and very seldomly when changing down it pops out of second ( remember it's a 4 speed)
Now this DID NOT HAPPEN BEFORE I PULLED THE TRANNY OUT,
I even had a set of locating pins to hold all gears in place, as per my sunbeam rapier gearbox rebuild manual I bought
It's not jumping out all the time and everything else is fine, and it drives nice
Any ideas fellas, do. I need to add if the box needs to come out again, which will be third time in 3 months, it could be a Hari Kari moment!
Cheers
Stu

Back To Top PM Quote Reply  

 Posted: 03-21-2018 02:55 pm
  PM Quote Reply
2nd Post
gmgiltd
Member
 

Joined: 07-10-2012
Location: Whitehills , United Kingdom
Posts: 168
Status: 
Offline
Hi Stuart, Had a similar issue with a five speed which was traced to a rubber linkage gaiter that I got from Rejen. It was putting a very slight tension on the shift lever which caused it to jump out of gear on the over run. Just a suggestion, might be worth checking.
Gordon

Back To Top PM Quote Reply

 Posted: 03-21-2018 09:25 pm
  PM Quote Reply
3rd Post
answerman
Member
 

Joined: 09-10-2012
Location: Little Chute, Wisconsin USA
Posts: 435
Status: 
Offline
Hey Stuart: I know this has been discussed before, there should be posts on this forum somewhere about it. It's something that seems to happen to the 4 speeds over time (mine does it occasionally in either 3rd or 4th gear if I don't make sure that it's properly in gear) and it had to do with something wearing out. If I remember it's one of those things where it's a very inexpensive part to replace/rebuild but involves ripping the transmission apart to fix. I just live with mine...

Back To Top PM Quote Reply  

 Posted: 03-22-2018 12:31 am
  PM Quote Reply
4th Post
Jensen Healey
Super Moderator


Joined: 03-11-2005
Location: San Anselmo, California USA
Posts: 983
Status: 
Offline
My memory tells me there's a rear flange nut that must be torqued to about 80 lbft or it slips out of gear.

Back To Top PM Quote Reply

 Posted: 03-22-2018 01:24 am
  PM Quote Reply
5th Post
Fred Barber
Member
 

Joined: 03-06-2018
Location:  
Posts: 1
Status: 
Offline
Is this relevant?

http://www.jensenhealey.com/forums/view_topic.php?id=85&forum_id=2

Back To Top PM Quote Reply  

 Posted: 03-22-2018 04:10 pm
  PM Quote Reply
6th Post
redracer
Member
 

Joined: 09-10-2012
Location: BROOKHAVEN, Georgia USA
Posts: 617
Status: 
Offline
Stuart: jumping out of 2nd gear is not as common jumping out of 3rd gear, especially when the car is decelerating quickly.
You said you stopped the tm. leaks? If you replaced the front seal, you would need to disassemble it somewhat(unlike the 5spd. in which the front has a cover plate--much easier). Without more info as to wen/how this happens(accelerating? decelerating?) I would guess the spring for the shift detent balls is too weak, and shimming would be necessary(yes, you will need to pull it out, etc.)The book calls for 35 lbs of force to move it(you may have to build a "jig" and use a fish scale to measure it).
In a somewhat related answer the 80 ft-lbs rear nut, that could be tightened by removing the rear housing(5nuts/bolts) and yes, you will "lose" you fluid.
However that has NEVER been a problem in all the 4spds. I've rebuilt/seen. If you have the tm popping out of 3rd gear, the FRONT large shaft nut may likely be loose if it has been rebuilt. To check this, put the lever into 3rd gear(engine off) and if there is for-aft movement of the shift lever, the nut has loosened and will eventually get ground up in the front bearing($$$$$$$). This nut(right hand thread-should have been left hand) needs Loctite and REPEENING HEAVILY after it has been torqued down.
I realize this is not your current problem, but it may help others.
Keep us posted(yes, I believe you will need to pull the tm and probably should do a full rebuild. The J-H manual for the tm is not too bad--compared to the engine section)
bruce

Back To Top PM Quote Reply

 Posted: 03-23-2018 03:16 pm
  PM Quote Reply
7th Post
DonBurns
Member
 

Joined: 09-18-2015
Location: Fullerton, California USA
Posts: 147
Status: 
Offline
Sounds like there are many possible causes, so this is just what it was for me. On my first JH in 1979, my 4-speed was jumping out of second. I had a shop rebuild it, and the cause turned out to be a bearing that was missing a needle (might have been a ball, but my memory was that the bearing was a needle bearing). This allowed a slight deflection in the shaft. It turned out that the repair of the bearing was all the tranny needed.

Back To Top PM Quote Reply  

 Posted: 03-23-2018 11:58 pm
  PM Quote Reply
8th Post
stuartmorgan
Member


Joined: 05-07-2013
Location: Melbourne, Australia
Posts: 39
Status: 
Offline
Evening Gents
This is really great reading and what a font of knowledge, thank you all
Ok I am going keep an eye on it, if it keeps happening I think it may need to come out
The box was fine until I started chasing and trying fix the leaks, which we did
FYI it was when I was changing down and below 50 km/h ( that's 31 m/ hr in funny talk ) so maybe it is the torque on the locator fork nut, or a bearing or both
Thanks gang
Have a great weekend
Stu

Back To Top PM Quote Reply

 Posted: 01-01-2024 10:56 pm
  PM Quote Reply
9th Post
Ralph H
Member


Joined: 03-13-2018
Location: 1974 Jensen Healey # 15681, New Brunswick Canada
Posts: 45
Status: 
Offline
love reading thru these old posts good info and still solving issues in 2024 Thanks

Back To Top PM Quote Reply  

Current time is 07:55 am  
> Jensen Healey & Jensen GT Tech > Engine & Transmission > Second gear popping out Top




UltraBB 1.172 Copyright © 2007-2011 Data 1 Systems