Gonna use the forbidden P word
Permatex
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Intake boot leak that won’t stay away
- Thread starter Woodstock1976
- Start date
Permatex
sparky4123
IN XS
I have had trouble with the replacement gaskets from MikesXS and others. Engine heat hardens and dries out the gaskets and they lose their seal. I have used Yamabond with reasonable success instead of gaskets. Also, “the right stuff” gasket maker seems to hold up OK.
Woodstock1976
XS650 Enthusiast
Does jbm say this on their website? I see where it says designed to not need the metal shrouds but I don’t see where it says about not needing gaskets
Woodstock1976
XS650 Enthusiast
I got the red kind brand new tube just in case
Just don't be THIS guy...
Gary, you don't understand. That excess around the inside diameter is to help atomize the mixture. Jeesh!!!
Woodstock1976
XS650 Enthusiast
I read that also but it doesn’t say about gaskets?
I stand corrected. I mis-read your question. Here is another clip from their site that may further clarify.
HamishTHaggis
XS650 Member
I had this issue with my '79. Even worse after i swapped out the original carbs for a pair of VM34s with v stacks. Picked up the billet aluminum manifolds from tcbros and the added length and rigidity plus thick boots has resolved it for me - so far 2.5 years as a daily without a recurrence.
Woodstock1976
XS650 Enthusiast
Ahhh I see thank you
Woodstock1976
XS650 Enthusiast
That was my next route if I can’t get this leak to go away
Woodstock1976
XS650 Enthusiast
Update I’ve received the jbm boots and right off the y look promising. The rubber fully encases everything. No metal showing through the rubber anywhere. I’m gonna see if it works with no gaskets as it looks like there’s enough rubber to form a good seal with out
Woodstock1976
XS650 Enthusiast
Update installED JBM boots with no gasket and it still leaked same location. Then tried the JBM boots with their gaskets dry no sealant. Leak in same location. Their boots seem exceptionally thin. Now I’ve added permatex red to some very thick aftermarket gaskets and installed boots waiting the 24 hours to install carbs and check for leaks again.
Leak location is circled in the picture. Also I checked the mating surface with a straight edge in every direction I could on both sides and couldn’t find any obvious deformation.
Leak location is circled in the picture. Also I checked the mating surface with a straight edge in every direction I could on both sides and couldn’t find any obvious deformation.
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Sure looks like it is overtightened and causing an arch in that area.
Woodstock1976
XS650 Enthusiast
I tried tightening it to what I thought was good first then I tried 80 inch pounds as I found that spec in a thread here. It leaked both ways. Always the same spot. I’ve also tried 3 different new sets of boots now too. I feel like it must be not flat somehow but I checked it with a straight edge and couldn’t see any weird spots any way I turned it
80 in. lbs. is less than 7 ft. lbs. . That is just a little more than finger tight.
Woodstock1976
XS650 Enthusiast
I did it with a torque wrench. Seemed a bit more than finger tight but either way I tried it both ways leaked both ways
Yes, that 80 in/lb spec is probably from me. I've used it for years all over the bike on most of the M6 fasteners and found it works well. It's definitely tighter than finger tight, lol, but not too tight to the point of deforming things or stripping screw holes. If you're using original style thick gaskets then they will require several re-torques because they're going to compress quite a bit. In fact, if you check the torque just after letting them sit overnight, you're going to find them loose.
I agree, it sounds like the flange is warped. I'd have at it with a nice flat sanding block and some 320 wet/dry paper to start, then finish with some 400. I'd cut a "custom" sanding block a little wider and longer than the flange face from some 1/4" steel plate. After just a few swipes, you should be able to see if the flange is warped.
I agree, it sounds like the flange is warped. I'd have at it with a nice flat sanding block and some 320 wet/dry paper to start, then finish with some 400. I'd cut a "custom" sanding block a little wider and longer than the flange face from some 1/4" steel plate. After just a few swipes, you should be able to see if the flange is warped.
It does look like it’s been overtightened. I think I’m seeing deformation of the rubber near the bolt. That said, the root cause seems to be the flange isn’t flat. Use 5T’s suggestions to check and remedy.
