Hello to all,
Couldn't find this specific topic anywhere in the site so hopefully this one hasn't been answered before. I've recently put my 1951 Javelin (NHY120) into the local classic mechanic to try to find the source of a new noise coming through. The noise is a very loud ticking/clacking sound, coming from the rear of the gearbox where it joins on to the propshaft. It rises and falls with roadspeed rather than engine RPM, and is most noticeable in 2nd and 3rd gear.
Engineer confirms no teeth missing and no swarf in gearbox oil, but the noise persists. He is a Ford classic specialist rather than Jowett, and not a gearbox / transmission specialist. He does know that the Jowetts suffered from problematic gearboxes in later years, and wishes to approach the problem with caution, asking me to ask the Jowett community whether they have any thoughts before removal or dismantling the whole thing.
Any advice would be most welcome!
Daniel Warren, based in Letchworth Garden City
Unusual new sound coming from GB / Drivetrain
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silverwing82
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- Your interest in the forum: Dad, Clive Warren, was a member for many years. Currently sharing a Jupiter, Javelin and Flying Fox with my brother and sister
- Given Name: Daniel
Unusual new sound coming from GB / Drivetrain
Daniel, owner of Javelin NHY120
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Keith Clements
- websitedesign
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- Given Name: Keith
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Re: Unusual new sound coming from GB / Drivetrain
I would first check the layrub coupling as they frequently wear. Then make sure the large nut on the end of the box holding the yoke to the layrub is tight.
If you are sure it is road speed, then it is not the clutch. So what could it be in the box?
Sometimes the selector forks break but this would usually mean difficulty in selection. It is more likely a washer has broken causing gears to have too much movement and perhaps hitting another.
You say ticking rather than grating. Well the speedo cable can make a ticking sound.
If you are sure it is road speed, then it is not the clutch. So what could it be in the box?
Sometimes the selector forks break but this would usually mean difficulty in selection. It is more likely a washer has broken causing gears to have too much movement and perhaps hitting another.
You say ticking rather than grating. Well the speedo cable can make a ticking sound.
skype = keithaclements ;
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silverwing82
- Posts: 2
- Joined: Fri Oct 08, 2021 8:21 pm
- Your interest in the forum: Dad, Clive Warren, was a member for many years. Currently sharing a Jupiter, Javelin and Flying Fox with my brother and sister
- Given Name: Daniel
Re: Unusual new sound coming from GB / Drivetrain
Hi Keith, well it turned out you were spot on in terms of where to look! 
Recently the midship bearing chassis mounts had become detached, and although fixed this had placed a strain on the prop - clearly. The problem turned out to be the bolts at the coupling had worked loose, the retaining pins almost sheared, and the noise resulting from the movement at the coupling.
Many thanks for the tip, we have replaced the bolts and pins and all is back to normal. I must also thanks my local mechanic, Kevin Saddler, who has applied a cautious and sensitive approach to all of the work he had recently performed for me, I recommend him to anyone in the North Herts / South Beds region.
Can't wait for Spring to get back on the roads!
Daniel
Recently the midship bearing chassis mounts had become detached, and although fixed this had placed a strain on the prop - clearly. The problem turned out to be the bolts at the coupling had worked loose, the retaining pins almost sheared, and the noise resulting from the movement at the coupling. Many thanks for the tip, we have replaced the bolts and pins and all is back to normal. I must also thanks my local mechanic, Kevin Saddler, who has applied a cautious and sensitive approach to all of the work he had recently performed for me, I recommend him to anyone in the North Herts / South Beds region.
Can't wait for Spring to get back on the roads!
Daniel
Daniel, owner of Javelin NHY120