Greater O rings, is the tech FAQ wrong?

Mouthfulloflake

ISJWTA member #2
Location
NW Arkansas
so I looked in the tech faq, and ordered these part numbers for a greater yamaha head.


Riva O-rings
ADA 701 O-Rings
riva head oring sizes 701/760
Shell seal:1/16" Bulk Buna-N
From the top down:
Spark Plug:118 Buna
2nd :031 Buna
3rd :043 Buna
Compression chamber : 153 viton

the compression chamber O ring appears to be correct.

and the cord stock appears to be correct.

the other 3 part dont fit anything on this head.

Spark Plug:118 Buna
2nd :031 Buna
3rd :043 Buna

I searched and found THIS thread..

http://x-h2o.com/showthread.php?t=8753&highlight=ada+rings

where cramminit says the combustion ring is 043

and the dome to shell rings are 020, and 024

from just looking at the diminsions, 020, and 024 seem like they would be the correct dash numbers for the domes.

so im wondering, are there newer and older styles of Riva and greater yamaha heads?

why is the faq wrong here?

the 043 buna ring is far too skinny for the combustion chamber seal.

do I have an oddball head?

or does the faq contain inaccurate data?
 

Crab

thanks darin...noswad!
Location
Seattle
Not certain, but I was lead to believe the Blowsion heads use the same rings. Let me know what you find out I have 2 heads that need rings.
 

Mouthfulloflake

ISJWTA member #2
Location
NW Arkansas
well, that might be the case!

the guy I bought the head from ( great seller BTW!) mentioned a blowsion kit for the rings.

But I had read that greater yamaha, and riva heads were the same.

in the faq, it listed Riva O ring #s, so I thought I had it licked.

apparently not!

if you can use any of the BAZILLION o rings I bought that I can't use, Ill gladly ship them to you!
 

Big Kahuna

Administrator
Location
Tuscaloosa, AL
well, that might be the case!

the guy I bought the head from ( great seller BTW!) mentioned a blowsion kit for the rings.

But I had read that greater yamaha, and riva heads were the same.

in the faq, it listed Riva O ring #s, so I thought I had it licked.

apparently not!

if you can use any of the BAZILLION o rings I bought that I can't use, Ill gladly ship them to you!

as far as construction goes, no they are not the same. Not sure on the orings though.
 

Mouthfulloflake

ISJWTA member #2
Location
NW Arkansas
after researching ive seen several TYPES of heads that were referred to as " greater " type.

IM guessing there were a few different types through the years.

I could measure them mark, but wheres the fun in that?
I mean ordering the RIGHT O rings on the first try, how boring!

haha
 

Big Kahuna

Administrator
Location
Tuscaloosa, AL
I know the Greater and Wammer heads are the same, believe they are both made by UMI. The blowsion may be the same. I think I remember reading also that protec domes fit in these but not 100%
 

Mouthfulloflake

ISJWTA member #2
Location
NW Arkansas
I know I can order a KIT from Blowsion, but for the same $20 I could have a bazillion O rings.

som i am trying to find the specs, or part number to order them from mcmaster car.

Ill measure them tonight ( If I have time)
 

Mouthfulloflake

ISJWTA member #2
Location
NW Arkansas
ive already got baggies full or parts for the ADA, and MRD heads, and of course, this greater yamaha head is different.

I even found some that I have to fit my MSD twist head...




Just order a pack of every dash and I am sure you will find one that will work, that is if you can find the time. LOL

Mark44
 
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