Yet another intake leak; time to siamese base deeper!
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Joined: Dec 2000
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From: SE NY
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Yet another intake leak; time to siamese base deeper!
The mechanic at Wilton Motors in CT recently isolated my latest oil leak as the rear of the intake base; I just noticed some green fluid on the top of the right side of the base.
So on the next "warm" day off it comes and I get a chance to extend the siamese cuts to 2" (from the current 1" depth) before I button it back up. I'm trying to push my usable RPM to 6k.
The mechanic suggested that I roughen the front and block lands with 80 grit paper before laying down the RTV.
Also, I plan to let it stand two days after laying the base on and torquing it down, then retorque the base and butten her up.
Now all I need is some dry weather with temps above 30deg F. :smash:
So on the next "warm" day off it comes and I get a chance to extend the siamese cuts to 2" (from the current 1" depth) before I button it back up. I'm trying to push my usable RPM to 6k.
The mechanic suggested that I roughen the front and block lands with 80 grit paper before laying down the RTV.
Also, I plan to let it stand two days after laying the base on and torquing it down, then retorque the base and butten her up.
Now all I need is some dry weather with temps above 30deg F. :smash:
Team Owner
Joined: May 2002
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Re: Yet another intake leak; time to siamese base deeper! (65Z01)
You have a mechanic? hehe.. I just lost all respect for you. J/K! :jester
80 grit sounds like it might do the trick. I just gouged mine with the razor blade to give it some nicks to grab onto.
I'm having a bitch of a time getting the RTV to seal my overdrive pan though. Seems if any fluid touches it before its completely set.. it melts away. There's got to be some better kind of sealer out there somewhere.
80 grit sounds like it might do the trick. I just gouged mine with the razor blade to give it some nicks to grab onto.
I'm having a bitch of a time getting the RTV to seal my overdrive pan though. Seems if any fluid touches it before its completely set.. it melts away. There's got to be some better kind of sealer out there somewhere.
Thread Starter
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From: SE NY
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Re: Yet another intake leak; time to siamese base deeper! (CentralCoaster)
Oh, I forgot to mention that I do all work in the parking lot so don't have access to the underside. After getting several diverse opinions as to the source of the oil leak while she was on a lift, I finally took her to a mechanic that had the dye & black light facility.
When I sealed the base I essentially followed the FelPro instructions as to RTV bead size; this time I will lay a substantial bead, as I found when I first opened it up.
RTV should be impervious to most any fluid; maybe you just need to clean away all traces of fluid and then allow a copla days for it to cure completely.
When I sealed the base I essentially followed the FelPro instructions as to RTV bead size; this time I will lay a substantial bead, as I found when I first opened it up.
RTV should be impervious to most any fluid; maybe you just need to clean away all traces of fluid and then allow a copla days for it to cure completely.
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Joined: Jun 2000
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From: Long Island, NY
Re: Yet another intake leak; time to siamese base deeper! (65Z01)
Jim,
I dimpled the front and rear sealing surfaces on the block with a center punch. Then lay a nice bead of RTV.
Also, after buttoning everything back up, I wait 24 hours before starting the car.
BTW, we only have 3 weeks till the first CC.
Vic
I dimpled the front and rear sealing surfaces on the block with a center punch. Then lay a nice bead of RTV.
Also, after buttoning everything back up, I wait 24 hours before starting the car.
BTW, we only have 3 weeks till the first CC.
Vic
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From: Boise ID
Re: Yet another intake leak; time to siamese base deeper! (Vic'89)
:iagree:
I'm certianly not a expert on this but I followed the below procedure which used to be on the tech tips and it has worked for 2 1/2 years so far (knocks on desk!)
Now take a fine point punch and hammer and punch a series of dimples on both ends of the block and on both ends of the manifold.
You will end up with about 30 or more dimples on each end when you're done. They should be positioned about 1/8 to 1/4 inch apart. You don't have to go deep, but make sure you've got dimples that you can catch with your fingernail. Be careful not to place the punch so close to the edges that you chip the block or intake material. It's kinda hard to chip it but there's no need to get closer than say 1/8th inch.
I'm certianly not a expert on this but I followed the below procedure which used to be on the tech tips and it has worked for 2 1/2 years so far (knocks on desk!)
Now take a fine point punch and hammer and punch a series of dimples on both ends of the block and on both ends of the manifold.
You will end up with about 30 or more dimples on each end when you're done. They should be positioned about 1/8 to 1/4 inch apart. You don't have to go deep, but make sure you've got dimples that you can catch with your fingernail. Be careful not to place the punch so close to the edges that you chip the block or intake material. It's kinda hard to chip it but there's no need to get closer than say 1/8th inch.
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Joined: Dec 2000
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From: SE NY
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Re: Yet another intake leak; time to siamese base deeper! (Vic'89)
Vic, I think I'll try the 80-grit and the center punch.
I know the clock is ticking; guess I'll be doing the job next to a 6' snow drift.
I know the clock is ticking; guess I'll be doing the job next to a 6' snow drift.
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Joined: Dec 2000
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From: Jacksonville Fl
Re: Yet another intake leak; time to siamese base deeper! (65Z01)
RTV should be impervious to most any fluid; maybe you just need to clean away all traces of fluid and then allow a copla days for it to cure completely.
If you want it to seal and last, you should go to the local dodge dealer and get the trans pan sealant. It is the best RTV in the world. It sticks and seals even when put on a trans pan that is wet with trans fluid. It's the only way to seal a dodge FWD transmission.
When I was a dodge mechanic ( trans rebuilder ) I had a hard time at first believing RTV should be used on their trans pans ( instead of gaskets ), but after seeing so many leaking pans from non-dodge shops that put gaskets on...the dodge way really does work.
So...if you also have a caravan or other FWD drive dodge...use the sealant next time you do a trans service. It is the ONLY method to seal them that works.
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From: Jacksonville Fl
Re: Yet another intake leak; time to siamese base deeper! (CentralCoaster)
I'm having a bitch of a time getting the RTV to seal my overdrive pan though. Seems if any fluid touches it before its completely set.. it melts away. There's got to be some better kind of sealer out there somewhere.
Team Owner
Joined: May 2002
Posts: 24,337
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Re: Yet another intake leak; time to siamese base deeper! (BBA)
Thanks for the tip! I'll have to check that out.
I just didn't wanna drain out all my expensive Redline ATF every time until I finally got a seal that worked. :crazy:
I just didn't wanna drain out all my expensive Redline ATF every time until I finally got a seal that worked. :crazy:
