[SEL] Herc cart progress update.

[Tommy Berry]

Hello Ill throw in my 2 cents worth on the lock washer debate. On modern
engines with no lock washers on the oil pans the pans have no gaskets
but they are sealed with an extremely high quality RTV sealant. The oil
pan is glued on and the  bolt load is low Thanks for the interesting
reading.

-----Original Message-----
From: sel-bounces at lists.stationary-engine.com
[mailto:sel-bounces at lists.stationary-engine.com] On Behalf Of Curt
Holland
Sent: Tuesday, June 01, 2004 1:26 PM
To: The SEL email discussion list
Subject: Re: [SEL] Herc cart progress update.

Rob Skinner wrote:

>Hi Curt,
>I'm too much of a gentleman to tell you that you are full
>of crap.  
>
Rob,
Ahh this is why we have the Nomex! Missy and I were discussing this on 
Friday night and she reminded me about the nuts and U-bolts on her 1914 
Hercules doctor's buggy. When we replaced the tapered stub axles she 
spent about 2 hours figuring out which nuts went on which U-bolt. Seems 
each nut would only fit on one stud location on the U-bolts. There are 
at least 8 or 10 U-bolts one each axle that hold the wooden runner to 
the top of the bowed steel axle and it took her a while to get the 
combinations worked out. She recalled that each nuts would only fit in 
one location and that it would only go on in one direction. So we 
grabbed a flashlight and went to the engine shed. Guess what, the 
rounded side of the square nuts was toward the surface being clamped.

Then Missy said, you've got all these engine carts laying around, lets 
look at them. There are 2 of the drop center Herc carts that the 5/7HP 
engines went on and 2 of the medium sized carts that the 3/5HP engines 
went on. All of theses carts appear to be completely original and 
undisturbed. About 70% of the square nuts have the rounded corner side 
facing the lockwashers! Admittedly this leaves 30% of them installed 
with the rounded side up, but it sure makes one wonder when the vast 
majority of the nuts are installed the otherway. Especially on 4 
different carts. Maybe I am nuts, but there are 4 carts in my yard with 
3/4 of the nuts with the rounded side towards the lockwashers. 'Tis a 
mystery.

On the lockwashers, perhaps I should have clarified gasketed vs. rigid 
connections. On "soft" clamps such as gasketed connections there is a 
benefit to the use of lockwashers. However, on steel to steel 
connections with no give, there appears to be little benefit to the use 
of lockwashers (bearing caps for example). Correct torque, bolt stretch,

and self locking (especially with fine threads) make the use of a 
lockwasher unnecessary. This is well documented in engineering books and

I can try to look it up if of interest.
I chose not to use lockwashers on the cart because of the amount of 
damage they do to pretty paint when the nut is removed. To keep things 
tight instead of lockwashers I decided to use the 242 removable Locktite

(blue). I've had to take several nuts back off and have been very 
pleased with how they have come back off. The first couple of turns are 
pretty tough and then it gets real easy. Best of all I haven't spoiled 
any of the pretty paint around it. Have only had to touch up the red on 
the nuts where the wrench was pushing on it.
If we look to modern engines we can see that lockwashers are being used 
less and less as understanding of their minimal benifits comes to light.

Rod caps, crank mains, and even transmission pans (yes, a gasketed 
joint), no longer have lockwashers on them because they tear up the base

metal when removed, and because they are completely unnecessary to keep 
the bolted connection tight.

Curt Holland
Gastonia, NC





 

_______________________________________________
SEL mailing list
SEL at lists.stationary-engine.com
http://www.stationary-engine.com/mailman/listinfo/sel