Author Topic: Sump plate  (Read 1476 times)

Offline CheeserBeezer

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Sump plate
« on: 04.03. 2025 07:23 »
Quite a lot of us use alloy sump plates. The down-side of these is they usually come supplied with allen bolts. The problem with this is that the threads aren't all that long in the sump and you can't be sure you're using the full length of them. Also, a stud locked up to its shoulder is much more secure. To overcome this issue I stay with the original studs and use tappet cover nuts which can be made to run into the aluminium sump plate. I turn the tappet cover nut down so that it takes a 5/16 washer, drill the sump plate 8.5 mm and that's all there is to it. Depending on the type of sump plate you are using you might need to grind a bit away to make sure you can get a socket on the nut. When fitting it's important to make sure that all the sleeve nuts fit easily and smoothly into their recesses to avoid straining the studs sideways. I dry-fit everything finger tight before using gasket goo.

Offline Greybeard

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Re: Sump plate
« Reply #1 on: 04.03. 2025 10:05 »
That looks like a proper job.  *good3*

I changed the studs for the ones that hold the rocker covers on as they are longer.

I winced a little at your use of the word 'socket', imagining some twerp hanging off a power bar or using a rattle gun.  *eek*
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Offline CheeserBeezer

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Re: Sump plate
« Reply #2 on: 04.03. 2025 17:07 »
That looks like a proper job.  *good3*

I changed the studs for the ones that hold the rocker covers on as they are longer.

I winced a little at your use of the word 'socket', imagining some twerp hanging off a power bar or using a rattle gun.  *eek*
Touch of a midwife required! I hold the socket bar right at the socket end.
I've come across a lot of original sump plates where PO's have used nylok nuts....another disaster waiting to happen!

Online muskrat

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Re: Sump plate
« Reply #3 on: 04.03. 2025 19:15 »
G'day CB.
I use the rocker box studs as Gb does and the extended nuts. Makes life so much easier.
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Offline jhg1958

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Re: Sump plate
« Reply #4 on: 04.03. 2025 20:50 »
I need to educating. What is the problem with nylok nuts?

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Offline CheeserBeezer

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Re: Sump plate
« Reply #5 on: 04.03. 2025 21:00 »
....nylok nuts. Their grip on the stud is greater than than the stud's grip in the crankcase so, tightening them up is OK but, when undoing, the stud will come out of the crankcase before the nut loosens on the stud. Some people would then just screw it back without taking the nut off the stud first which creates the same problem as using allen bolts, i.e. the thread wears out in the crankcase, and you can't be sure that you're using all the thread in the alloy.

Offline bikerboy

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Re: Sump plate
« Reply #6 on: 05.03. 2025 17:22 »
I have to say 90% of studs I loctite in to avoid them coming out with the nuts, the ones on the barrel base are a good for instance the amount of them that used to wind the stud out before threadlock was introduced.


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