Points / Advance Housings Delete Covers: Heiden Tuning and Shell

patentgeek

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I expect some of you are familiar with the points/advance housing delete covers offered by Hoos Racing and Heiden Tuning. If a crank timed ignition is used (e.g., Vape/PowerDynamo, Electrex, PVL, etc.) these allow for removing the points/advance housings to clean up aesthetics.

Heiden Tuning Points/Advance Housing Delete Covers

Hoos Racing Shell Points/Advance Housing Delete Covers

I bought the Heiden Tuning covers and new o-rings and gaskets (per the Heiden Tuning recommendation) from Mikes XS. But I'm scratching my head about the o-ring + gasket combination. The Mikes XS gaskets sit between the o-ring and the cover aluminum surface such that the o-ring sits on the gasket and not the cover itself - - - which is very odd from an engineering point of view. It really seems like there should be an o-ring OR a gasket, but not an o-ring AND a gasket. But I know the parts manual calls for both on the stock points/advance housing covers.

I'm probably overthinking this given once these covers are installed, they won't be coming off since there's nothing under them to adjust. So whatever whatever works to keep the oil inside the cover should be fine. But the o-ring + gasket combo annoys my mechanical engineering sensibilities.
 

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I have installed the Shell covers with seals and just the gaskets.
 
I installed the Shell covers with just the gasket. leaked like Niagara Falls.:yikes: The ID of my Shell covers was too big for seals. O-ring and gasket is the answer.:thumbsup:
 
I have installed the Shell covers with seals and just the gaskets.

Not sure what this means. O-rings only? Gaskets only? Or o-rings and gaskets?

The pic of the Shell coveres on Hoos Racing only shows gaskets, but that's not dispositive as to whether they recommend using o-rings too.

I took a fresh look at the head design this morning. The problem with the o-ring sealing area is that there's a seam where the two surfaces come together. As opposed to a unitary surafce that is more typical of o-ring applications. The o-ring is more or less likely to leak at that seam, depending on tolerances. Gasket + sealant (e.g., Yamabond) is more tolerant of seams.

Another problem I see with using o-ring + gasket is that the gasket thickness reduces the o-ring pre-load. And since gasket thickness tends to be a bit inconsistent depending on the manufacturer, there could be large variations in the o-ring pre-load, which isn't great from an o-ring seal design perspective.
 
I installed the Shell covers with just the gasket. leaked like Niagara Falls.:yikes: The ID of my Shell covers was too big for seals. O-ring and gasket is the answer.:thumbsup:

Do not understand what "The ID of my Shell covers was too big for seals" means because "seals" could mean either the o-ring or the gasket. Are you saying the gasket didn't fit?
 
Not speaking for Halfmile & I'm sure he's installed more; I got my Shell covers a few months ago from Hoos and put new factory cam seals in the covers and installed them with the supplied gaskets only (no o-ring). The gaskets were the green variety - that usually means Athena brand - same as stock cam cover gaskets. No leaks & no issues in several hundred miles to date.
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Not speaking for Halfmile & I'm sure he's installed more; I got my Shell covers a few months ago from Hoos and put new factory cam seals in the covers and installed them with the supplied gaskets only (no o-ring). The gaskets were the green variety - that usually means Athena brand - same as stock cam cover gaskets. No leaks & no issues in several hundred miles to date.

Ah, now I get it - - - the Shell covers are designed to use cam seals. I didn't realize that because all of the pics on Hoos Racing only show the outer facing side of the covers. My Heiden Tuning covers didn't come with installation instructions, but it doesn't look like they are configured to use cam seals.

Interesting that HalfMile's Shell covers are not compatible with cam seals but yours are. Maybe the design changed?
 
IDK - perhaps - I just ordered them, along with cam seals, because that made sense to me. The seals were the expected fit in the covers (snug with seal driver). No instructions - I just winged it (typical MO):D
 
I tried seals in my Shell covers and they were so loose they fell right out. ID was way too big. Factory uses seals, gaskets and O-rings. :thumbsup: Makes sense to me.:shrug:
 
I tried seals in my Shell covers and they were so loose they fell right out. ID was way too big. Factory uses seals, gaskets and O-rings. :thumbsup: Makes sense to me.:shrug:

True, but with the OEM ignition setup, the cam seals are required to prevent oil from migrating into the points and advance covers. With the Shell covers, I'm not sure if the cam seals really do anything? But I don't know what the inner facing side of the Shell covers look like.
 
The Shell cam covers I sell do not take seal, just the gasket, if they leak, One problem could be you cam bearings are not in all the way, I did have one the the lip on the inside was to tall and had to file down, but other then that I have seen no issues.
 
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