How is the cooling fan fixing nut held in place on the Javelin. On my fan the nut is a castle nut with a wire twisted through the shaft. Is this normal or should it be a split pin.
Thanks for any info.
Cooling fan fixing
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Barry20383
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Nick Webster
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Re: Cooling fan fixing
A split pin is a neater and more professional looking solution. I have seen Nyloc nuts used on fan spindles and I am not aware of any failures with this approach, particularly if you include a dab of Loctite too.
If you have had the pump assembly off don't forget that when it goes back the struts should have Thackeray washers (double turn spring washer with an offset to allow it to compress evenly) with the nuts tightened to allow a bit of movement in the spring or you will have a vibration problem. Here also the nuts are split pinned in position, or they definitely will come off.
Nick
If you have had the pump assembly off don't forget that when it goes back the struts should have Thackeray washers (double turn spring washer with an offset to allow it to compress evenly) with the nuts tightened to allow a bit of movement in the spring or you will have a vibration problem. Here also the nuts are split pinned in position, or they definitely will come off.
Nick
JCC Member
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Barry20383
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Re: Cooling fan fixing
Thanks for the info as could not see in the service manuel. Will take out the wire and fit a split pin.
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David Morris
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Re: Cooling fan fixing
Hi Barry,
Is your cooling fan a true 'X' or the St. Andrews cross? On either type, check the root of the blades for cracks where they join the boss. The fan assembly is not one of Jowett's finest masterpieces and suffers from metal fatigue.
Most Javelin owners will carry a spare cooling fan strut in their tool box. The 'foot' of the strut, where it is forged from the round section to the flat 'foot' that carries the fixing hole, can fracture here. This leads to the fan assembly twisting round and the fan hitting the radiator core.
Easy to replace the strut by the roadside, but only if you have a spare!
As Nick says, the nuts on the 'foot' fixings are deliberately not tightened down, to allow some flexibility but the nuts should be split-pinned and Thackeray spring washers fitted.
All the best,
David
Is your cooling fan a true 'X' or the St. Andrews cross? On either type, check the root of the blades for cracks where they join the boss. The fan assembly is not one of Jowett's finest masterpieces and suffers from metal fatigue.
Most Javelin owners will carry a spare cooling fan strut in their tool box. The 'foot' of the strut, where it is forged from the round section to the flat 'foot' that carries the fixing hole, can fracture here. This leads to the fan assembly twisting round and the fan hitting the radiator core.
Easy to replace the strut by the roadside, but only if you have a spare!
As Nick says, the nuts on the 'foot' fixings are deliberately not tightened down, to allow some flexibility but the nuts should be split-pinned and Thackeray spring washers fitted.
All the best,
David
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Barry20383
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Re: Cooling fan fixing
Ok will check what fan is fitted and check the struts and fan blades.
The water pump shaft is the later type with an oil hole in the centre and level hole underneath.
Thanks.
The water pump shaft is the later type with an oil hole in the centre and level hole underneath.
Thanks.
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Barry20383
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- Your interest in the forum: Have recently sold my Bristol 401 classic car and am now thinking of buying a Jowett Javelin
- Given Name: Barry
Re: Cooling fan fixing
Is it possible to get better fan fixing struts perhaps from JSD to eliminate the weak originals .
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Nick Webster
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Re: Cooling fan fixing
My view is that the struts are fine if assembled correctly. Fractures can frequently be attributed to stress caused by tightening everything up so it cannot move. The later assembly has threaded fastenings where the struts attach to the tube and I use Thackeray washers at this end too. Earlier ones just had a peg and split pin and it is not so easy to set the tiny bit of slack that is required.
With all this it is important that that another of the pump's weak points is given the best chance of success. The rubber hose on the inlet side must be good and straight. Modern hoses are in my opinion a bit soft and easily distort. Over the years there have been several good suggestions about how to improve things with varying degrees of engineering expertise required. Personally I am lucky enough to have supplies of heavy duty commercial vehicle hose that I cut lengths off as required.
Nick
With all this it is important that that another of the pump's weak points is given the best chance of success. The rubber hose on the inlet side must be good and straight. Modern hoses are in my opinion a bit soft and easily distort. Over the years there have been several good suggestions about how to improve things with varying degrees of engineering expertise required. Personally I am lucky enough to have supplies of heavy duty commercial vehicle hose that I cut lengths off as required.
Nick
JCC Member