Sump Studs v Bolts

[Rick F]

I currently have the engine out of my 1929 Chummy-based special and am considering replacing the sump bolts with 1/4 BSW studs and nyloc nuts.

I know this mod has been mentioned in other threads and I have two questions:

1.  Is it worth the effort?

2.  I know nothing about Loctite, but assume that the stud will need a degree of sealing in the crank case. In that case, what grade of Loctite (or other sealant) would you recommend?

[Alan]

Yes and I use loctite 5980

[Steve Jones]

Over a period of time I've changed all my engines to 1/4" BSW studs and Nylocs. I wouldn't change back. Once the stud is in place and tightened, that's it. No risk of damage to the crankcase threads by the removal/re-fitting of sump bolts and the nature of the stud means that the possibility of oil leaking down the thread as can happen with bolts is removed. I've never Loctited the studs in although I see no reason not to. Just made sure the crankcase threads are clean and oil free by thorough use of brake cleaner and then fitting the studs and tightening them in by carefull use of a roller stud extractor/fitter. Although it will upset the purists, 1/4" UNC studs and nuts work equally as well given the similarity of the two threads.

Steve

[Alan]

It’s ok Steve. I’m not upset.

[AustinWood]

I have no problems using bolts.
We have a cast alloy sump that has to be removed before the engine comes out. I think studs would make things more awkward.

[Chris KC]

I have no problems using bolts.
We have a cast alloy sump that has to be removed before the engine comes out. I think studs would make things more awkward.

Likewise, I think studs would make my cast alloy sump impossible to remove in situ.
(Certainly harder than it is now using slotted screws).

[falcott]

I've never yet removed the engine from my '36 Special, so is there any reason that the sump has to be removed first? I'm interested in the conversion to studs because of oil leaks.

[Nick Salmon]

On any standard Seven, will this conversion to studs allow the sump to be removed/replaced without difficulty?

[Charles P]

I have a "semi-deep" aluminium sump on my car and use studs. You need to relieve a front corners a little (less than an 1/8") to make it removeable with the engine in situ.
I learnt this the hard way in the paddock at Wiscombe Park over lunch. On that occasion I had to loosen the front engine mounting bolts and use tyre lever to get it off.
It went back together and I still made the afternoon runs

[Rick F]

I have never removed the sump prior to removing the engine on any of my 7s, all of which are fitted with the standard pressed tin version.