Jb3 gearbox advice?

[nudger2802]

JB3 or JB1 gearbox advice?

Hi Folks!

I am after a bit of advice please!

I have got a 1994 Renault 21 1.9 Diesel Savanna (Dont Laugh!) and I am pretty sure my diff decided to give up the ghost yesterday.

I was driving along as normal and suddenly a slight dull occasional knocking started and the steering occasionally pulled to the left getting worse as I carried on. I was on country lanes and couldnt really stop safely so carried on for about 5 miles untill I could find somewhere safe and under a street light.

When I stopped I checked & topped up the gearbox oil (luckily I had a couple of litres in the boot) and it took about 1.5 litres (its been leaking) and when it started to run out the filler plug i got a mix of fresh oil and mayonaise(n). I reversed out of where I had parked and got real bad clunking on taking up drive.

As I drove forward the clunking wasnt quite so bad but still really noticeable on take up of drive and cornering and seemed to get a bit worse as I drove the 10 miles home, when cruising at speed there is no clunks and the gearbox is really smooth with no whine or any unusual noise, only clunking on cornering or under load.

I thought it might be a drive shaft from the symptoms but on jacking the car up today found that if I rotate either front wheel it goes so far then locks up against something before turning any further suggesting the problem is the diff.

Has anyone else had a similar problem to this and found it to be something really stupid or am I right in thinking I am in the market for a new gearbox?

Also does anyone know if all JB3 gearboxes are interchangeable apart from the actual ratios?

My gearbox code is JB1S34 and its mated to a F8Q710 1.9 Diesel.

Am I right in thinking this is a JB3 box?

At 196750 miles I dont think its done bad if the gearbox has finally given up the ghost lol:lol:

Thanks,

Nige

 

[nudger2802]

Just spotted the article on the circlip problem where, the circlip breaks and the sungear lifts away from the planet gears.

Is it possible the car might still drive if this has happened, if for example the circlip hasnt come all the way out or the driveshaft somehow is putting enough force against the sungear to keep it engaged enough to drive but giving slightly under load?

Any one got any suggestions out there???????????

 

[The T.I.B.]

It's a JB1 box (the first part of the gearbox code)

Certainly doesn't sound good. You can investigate to a certain extent by draining the box oil and removing the n/s shaft. Then you'll have access to the circlip etc.

 

[nudger2802]

The code is what confused me? According to the Haynes manual and the actual Renault workshop manual I have a copy of it should be a JB3 but like you suggest the code does say JB1.

Are the boxes interchangeable? If not, other than a 21 1.9 Diesel what was the JB1 fitted to? Any suggestions?

I am gonna pull the near side shaft in the morning and have a peer inside to see whats happening in terms of the circlip.

I am thinking its more likely the diff bearings have gone though tbh meaning total gearbox stripdown to replace, hence easier and cheaper to replace box, but I am hopefull with this circlip issue:lol:

Cheers

 

[The T.I.B.]

the JB1 box was found in a few cars I think, possibly clio & R19 so you should be able to pick one up.

A JB3 would very likely fit but the ratios would not be ideal.

 

[nudger2802]

Thanks.

Found a few boxes on ebay but there seems to be a few different casings on the JB1's I have seen pictures of. The mounting on top of the box and the cut outs on the top of the box where it bolts to the engine block being the main areas.

Found one off a 1.6 Megane Petrol quite cheap that looks similar to mine and local that I might go for.

There is one off a 1.2 2002 clio on there too for only £15 with real low milage but like I say the casing looks different and I suspect the box would be a lot weaker and the gear ratios being miles off only coming off a 1200?

 

[The T.I.B.]

Not sure about newer boxes e.g. 2002 as the speedo drive is electronic on those rather than cable like yours

Also I've tried attaching a file to this post, see if you can read it. It contains details about the box ratios.

 

[nudger2802]

Many thanks for the manual. I was trapsing the internet most of yesterday trying to find a copy of that lol:lol:

I am still a bit confused though as according to all the Renault manuals I have mine should be a JB3 box and not the JB1S34 that is fitted and it left the factory with??????????????? Oh well who knows what goes on on production lines lol

I know mines the origional box as I have known the car from new and other than for clutch changes the box has never been out.

So other than getting the ratios somewhere near looking at the manual any
JB1 or JB3 box will fit as long as its got the cable speedo drive and not the electronic type?

Technically I suppose all F series engines have the same mountings, petrol or diesel, I guess?

Anyway off to take the N/S driveshaft out and check that circlip now whilst I got a bit of sunshine.

Thanks,

Nige

 

[nudger2802]

After spending most of the morning trying to undo rounded off driveshaft to gearbox bolts I finally got it apart.

The circlip is still there in the groove and perfectly intact but the thrust washer has snapped and bent like a cork screw so I think that the problem.

Obviously the circlip is still holding the sungear in place but without the washer is letting the sun gear come away from the planet gears when under load.

I have been and ordered a new circlip and thrust washer from Renault and should hopefully have it in the morning.

The parts guy said that mine should be a JB3 box according to his screen and was well confused when I said it was a JB1, he didnt want to order the bits, saying they wouldnt fit untill one of their mechanics walked in and said they were all the same when I asked his advice, so fingers crossed they will be the right ones and it will be driving again tomorrow.

The Renault mechanic asked me if I had a heavy right foot saying thats what usually causes he washer to bend but when I told him no and the car had done almost 200,000 he didn't beleive it was the origional box even though I know it definately is.

 

[The T.I.B.]

Well that's an easy fix so that's good news.

However I've heard stories about them not lasting once they've popped once, a bit like people with dislocated limbs I suppose. But give it a go!

The circlip can be a nuisance to get in even with large circlip pliers, I've had success before with needle nose pliers instead.

 

[nudger2802]

Well that's an easy fix so that's good news.

However I've heard stories about them not lasting once they've popped once, a bit like people with dislocated limbs I suppose. But give it a go!

The circlip can be a nuisance to get in even with large circlip pliers, I've had success before with needle nose pliers instead.

Certainly is, just hope its not caused anymore damage.

I am putting in a new circlip as well as a new washer so hopefully it will last, plus it aint exactly a racing car so it dont get the traffic light drag strip treatment lol

As long as the groove in the casing isnt too worn i cant see it being a problem.

I am more worried about getting the old circlip out than the new one in tbh. I think if I can get the new one to sit just inside the housing then gently tap it home with a socket that fits snug in the hole it should just slide in and click into place. Thats the theory anyway, I will probabbly still be sat there Christmas day trying to get the bloody thing to fit lol

 

[nudger2802]

Its back up and running :mrgreen:

Job done and driving round lovely, done 50 miles so far with no probs.

Old circlip just popped out with long nose pliers and new washer and circlip went straight in with no worries using a pair of long nose mole grips to squeeze the circlip together. Just released the mole grips when it was in the groove and hey prestoin it popped.

Just a tip to anyone after gearbox oil cheap, went to 3 local indipendant motor factors today and they all wanted over a fiver for a litre of EP 80/90 and between £13 & £18 for 5 litres.

Had to pop to Wilkinsons to get some Christmas crap to keep the missus and kids happy and they had Comma EP80/90 for £2.31 per litre:mrgreen: BARGAIN!!!

Thanks for all the advice.

Nige

 

[Neal R19]

Excellent!

This right here is exactly what this forum is about.

Always satisfying to see someone ask for help, have it given and the problem resolved to a happy ending!

 

[The T.I.B.]

bon.

 

[nudger2802]

Once again thanks for the help. Off on a 60 mile round trip in a bit and then thr big test for it Sunday on a bout a 200 mile round trip into deepest darkest wales so fingers crossed:lol:

Thanks,

Nige

 

[bidderman1969]

or a saturday trip to the xmas meet? :mrgreen: :lol:

 

[nudger2802]

Wish I could make it. I got a Job interview the other side of Birmingham at 3.30pm Saturday and a serious lack of funds with it coming up to Christmas and bein on the rock & roll at the moment which aint good, hence me having to go to deepest wales on Sunday to get a second hand ebay find for my sons Christmas present:cry: I feel like a right tight arse but needs must I guess if it meens saving over £100 in the long run. Lets hope I can make up for it next year if I get this job.

Nige