View previous topic :: View next topic |
Author |
Message |
chrisk Member
Joined: Apr 22, 2012 Posts: 119 Location: the Netherlands
|
Posted: Mon Nov 12, 2012 4:29 am Post subject: Question Insulator(gasket)WO-806271,Carburator YS950S |
|
|
Why did the Insulator (gasket) another form as the flange of the throttle valve body?
|
|
Back to top |
|
|
wesk Site Administrator
Joined: Apr 04, 2005 Posts: 16258 Location: Wisconsin
|
|
Back to top |
|
|
wilfreeman Member
Joined: Mar 13, 2006 Posts: 1079 Location: Richburg, SC
|
Posted: Mon Nov 12, 2012 4:39 pm Post subject: |
|
|
I don't understand the question - do you mean why is the gasket shaped differently than the throttle body flange? _________________ Matt
1953 M38a1
1964 USMC M38a1
'51 USMC M100 trailer, '54 M100 trailer, '90 M101a1 trailer
Http://wilfreeman.wordpress.com (M38a1 build blog)
http://m38a1usmc.wordpress.com (USMC M38a1 rebuild blog) |
|
Back to top |
|
|
chrisk Member
Joined: Apr 22, 2012 Posts: 119 Location: the Netherlands
|
Posted: Tue Nov 13, 2012 7:51 am Post subject: |
|
|
It is clear that the gasket is reversible
The question: the openings of the original gasket do not match with the openings of the throttle flange. Why not? |
|
Back to top |
|
|
wilfreeman Member
Joined: Mar 13, 2006 Posts: 1079 Location: Richburg, SC
|
Posted: Tue Nov 13, 2012 8:25 am Post subject: |
|
|
Gotcha - sorry I can't answer your question though. It does look like it would perform better if the gasket was cut out to match the ports in the throttle body like your picture shows. But, on the other hand, maybe Willys figured out by testing that the engine produced more torque or hp with the port covered. It is clear that since the port is recessed that it is not blocked by the gasket - is this a vacuum port, maybe (I haven't looked at the manual in detail). I'm just picking at atraws here - I'm not a mechanic. _________________ Matt
1953 M38a1
1964 USMC M38a1
'51 USMC M100 trailer, '54 M100 trailer, '90 M101a1 trailer
Http://wilfreeman.wordpress.com (M38a1 build blog)
http://m38a1usmc.wordpress.com (USMC M38a1 rebuild blog) |
|
Back to top |
|
|
Xamon Member
Joined: Sep 18, 2012 Posts: 589 Location: South East Saskatchewan
|
|
Back to top |
|
|
wilfreeman Member
Joined: Mar 13, 2006 Posts: 1079 Location: Richburg, SC
|
Posted: Tue Nov 13, 2012 9:38 am Post subject: |
|
|
Are the 38 and 38a1 throttle bodies the same - maybe that's it. _________________ Matt
1953 M38a1
1964 USMC M38a1
'51 USMC M100 trailer, '54 M100 trailer, '90 M101a1 trailer
Http://wilfreeman.wordpress.com (M38a1 build blog)
http://m38a1usmc.wordpress.com (USMC M38a1 rebuild blog) |
|
Back to top |
|
|
Xamon Member
Joined: Sep 18, 2012 Posts: 589 Location: South East Saskatchewan
|
|
Back to top |
|
|
wesk Site Administrator
Joined: Apr 04, 2005 Posts: 16258 Location: Wisconsin
|
Posted: Tue Nov 13, 2012 10:36 am Post subject: |
|
|
The holes are that shape to insure reversability and to not weaken the gasket. The larger "U" shaped cuts would have reduced the gasket's two edges to almost nothing. Small diameter holes with larger relief areas is common in fuel metering devices but the gasket has to at least have a hole equal to the diameter of the actual passageway when the passageway connects to an opposite passageway between the two parts. In this case there is no matching passageway in the cylinder head for those two shown in the photo at the top of the page. It can be assumed that the larger bore to accomadate the higher volume flow for the M38A1's F134 required slightly mor vacuum collection space in the area of the gasket and the slot sized used was all that was needed to operate the vacuum circuits in the carb.
The m38A1 (YS950S) carb throttle bore is much larger then the M38 (YS637S) throttle bore and the 637S does not have the same passageways. Therefore no interchange capability.
The carb to manifold gaskets are designed very differently for the two carbs.
This M38 base gasket does not have the hole thru it for the bottom vacuum port you see in it's base.
The throttle body for the YS950S (M38A1 & M170) is 1-897. The throttle body for the YS637S (M38) is 1-508S. Apples and oranges here! _________________ Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100
Mjeeps photo album: http://www.willysmjeeps.com/v2/modules.php?set_albumName=Wes-Knettle&op=modload&name=gallery&file=index&include=view_album.php |
|
Back to top |
|
|
wilfreeman Member
Joined: Mar 13, 2006 Posts: 1079 Location: Richburg, SC
|
Posted: Tue Nov 13, 2012 5:36 pm Post subject: |
|
|
Well there ya go chrisk - if anybody can give you an answer, it will be Wes! Thanks Wes! _________________ Matt
1953 M38a1
1964 USMC M38a1
'51 USMC M100 trailer, '54 M100 trailer, '90 M101a1 trailer
Http://wilfreeman.wordpress.com (M38a1 build blog)
http://m38a1usmc.wordpress.com (USMC M38a1 rebuild blog) |
|
Back to top |
|
|
Cacti_Ken Member
Joined: Apr 20, 2005 Posts: 1021 Location: Silsbee, Texas
|
Posted: Tue Nov 13, 2012 8:24 pm Post subject: |
|
|
"should use a thin gasket 1A-65 above and below the difuser"
I did wonder about that when I mounted the carburetor back when. I guess I should have asked. However, On my carburetor, the mounting studs are lacking a little length for putting a gasket on each side of the difuser. It's been running now for over 5,000 miles. _________________ Tropical Veteran
35th Inf. Reg. "CACTI" 4th I.D. VN
Amateur Radio K5XOM |
|
Back to top |
|
|
wesk Site Administrator
Joined: Apr 04, 2005 Posts: 16258 Location: Wisconsin
|
|
Back to top |
|
|
chrisk Member
Joined: Apr 22, 2012 Posts: 119 Location: the Netherlands
|
Posted: Wed Nov 14, 2012 4:01 am Post subject: |
|
|
Wes, thanks for the detailed explanation, it is now quite clear.
Also Matt thanks for thinking.
Best regards from the Netherlands, Chris |
|
Back to top |
|
|
|