Hymer B644 Fiat Ducato Gearbox lost 5th gear (1 Viewer)

[reynardracer]

Thanks Lee I will check it out tomorrow and make a decision. Many thanks for your help.

 

[reynardracer]

I assume there is a drain plug on the bottom somewhere!

 

[Lee27]

Hi Peter

Yes; number 15 in the image above, i think it will be obvious once you get under to look, at the bottom of the diff.

good luck mate

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[reynardracer]

What is the best way to refill it through the reverse light switch? Do you need to run a long piece of pipe down to the hole and fill from the top?

 

[reynardracer]

Started the job and first problem is that there is no 'C' clip on the main gear but a round 'nut' with a tabbed washer underneath that you bend up. Any one know how to remove this 'nut' without a proper tool. Help!

 

[Jaws]

I think you will find an ordinary 12 sided socket will fit it perfectly

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[reynardracer]

Ok so the job is done, not as easy as some might say but nine the less done. Here is a couple of tips and or issues I found.
The replacement parts bought from eBay 'onestop gearbox shop' were Ok except for the synchro hub that was a real pig to get onto the splines. It was obvious that this part was not a meticulously machined as the original and took some getting onto the splines with the use of a gently persuader. Tip here is to cable tie the synchro hub together to stop the ball bearings getting out as you tap it into place. Then cut the cable ties obviously.

We didn't drain the oil in case we couldn't get it done, but after draining the oil decided that as it all came out with the cover off we should be able to refill it through the drain hole in the bottom of the gearbox with the cover off. Yet to prove that theory.
One question, what oil is recommended for this gearbox. Can't seem to find what is brand is recommended.

Thank you to everyone who has assisted me during this time as you have all been most helpful.

Hopefully it will now just be a case of filling with oil and driving away.

Cheers
Peter

 

[Ivory55]

Fiat forum . Com . That is a fiat forum with ducato vans on , might know the right oil for your gearbox.

 

[Lee27]

Ok so the job is done, not as easy as some might say but nine the less done. Here is a couple of tips and or issues I found.
The replacement parts bought from eBay 'onestop gearbox shop' were Ok except for the synchro hub that was a real pig to get onto the splines. It was obvious that this part was not a meticulously machined as the original and took some getting onto the splines with the use of a gently persuader. Tip here is to cable tie the synchro hub together to stop the ball bearings getting out as you tap it into place. Then cut the cable ties obviously.

We didn't drain the oil in case we couldn't get it done, but after draining the oil decided that as it all came out with the cover off we should be able to refill it through the drain hole in the bottom of the gearbox with the cover off. Yet to prove that theory.
One question, what oil is recommended for this gearbox. Can't seem to find what is brand is recommended.

Thank you to everyone who has assisted me during this time as you have all been most helpful.

Hopefully it will now just be a case of filling with oil and driving away.

Cheers
Peter

Hi Peter

The recommendation for the transaxle is tutela matryx @ SAE 75w-80 EP synthetic that complies with API GL 5, obviously the brand doesn't really mater it's the specifications that do, quantity is 2.7 litres (2.43Kg) regardless of engine size. that's from my manual (2002) and the spec and quantity i used, i have seen older manuals stating as little as 1.9 litres (do you have yours?), but i'm aware of people that have been advised from fiat to use the newer larger quantity of 2.7 and have seen an older manual that has been updated, by fiat, with a sticker amending the quantity to 2.7.

I don't know the nature of your failure but mine involved lots of broken dog teeth and having seen the shrapnel that came out whilst flushing the box (which includes the diff) several times, i'm glad i did it. something to possibly keep in mind if you are intending to simply refill and drive off.

Lee

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[reynardracer]

HI Lee from the research I have done I would agree with what you said. We certainly drained a great deal of oil out. However there was very little residue in it, in fact it was very clean. The sump plug did have a great deal of shrapnel on it and there is also a magnet in the gearbox which hopefully picked up all the other bits. There was a few 'teeth' in the end cover but the rest of the dog teeth just seemed to be ground down. All in all a bit of a pain in the backside and something that once you have done it you are surprised that Fiat could expect it to work at all. Still such is life. Many thanks for your help and assistance on this matter.

Peter

 

[reynardracer]

Lee,
Out of interest what technique did you use to flush it out. Thought I might give it a try.

Thanks
Peter

 

[Lee27]

Hi Peter

From memory my chain of events were

Drain oil and remove 5th case and 5th gear/synchro etc
Assess damage and order part
Clean up and remove any debris I found in the gearbox
Replace plug and case

I then did the following steps about four or five times, each time the sieving exercise removed less and less shrapnel until it didn't seem to benefit

1. Sieve old oil from one container to another
2. Fill gearbox with old oil through breather
3. Remove plug to drain oil then replace plug

I then bought new oil cheap from a friend in the trade, fitted the new gear and the gear cover with the correct sealant (my cover uses sealant not a gasket) and filled the correct quantity of oil. I ran the van a few times to ensure the oil was circulated around the box and got up to temperature etc, then drained and filled with new oil a second time and considered the job done. When I drained the oil in this stage I ensured it was done whilst the oil was still hot/warm.

Hope this helps

Lee

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[reynardracer]

Excellent. Many thanks

 

[reynardracer]

Follow-up from 5th gear replacement.
Drove down the coast to Weymouth on Friday almost to scared to put it into 5th but did so with due care. It jumped out once or twice which was odd. Used 5th sparingly. Need some tips on driving now. Here is what I was doing: Usual 1st, 2nd, 3rd changing at around 3000 rpm. Using 4th most of the time again to 3000 rpm which did seem to be working the engine a bit much. Dropped into 5th around 90 Klms per hour and that gave me around 2400 rpm. As soon as I came to a hill or the rpm dropped below 2000 I dropped down to 4th gear again. Is the correct approach? Bit worried I am overworking the engine now! Popping out of 5th gear was a bit worrying but put that down to an inferior gear set as was unable to get a genuine Fiat replacement set. Any suggestions gladly received.

Peter