Dowty (bonded seal) washers vs copper washers - converter housing bolts

thunder550

Active member
Apr 2, 2013
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If it was mine, I would just chamfer the hole and put an o ring on the bolt. Kind of like the transmission cooler line fittings

The pump bolt that appears to be leaking has the factory rubber washer on it already, and I put RTV under the head of all the case bolts, including the one that looks like it's leaking. I also put thread sealer on all of the pump and case bolts. That's why I'm at a loss. The area under the converter snout looks like it's dry, so I don't think it's the converter seal or the pump o-ring. I've checked the converter itself both times I've had the trans out and there's no fluid on it anywhere, so I don't think it's coming from the converter itself. Makes no sense to me at all.
 

Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
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You gotta have a hairline crack somewhere or warp, chris. I would change the bell housing.

While your in there, you might as well mod the converter flow valve to stop pressure drop and up the main line pressure.
 
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clrussell

pro-procrastinator
Sep 23, 2013
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I’ve seen a couple stock converters leak somewhere and thought it was a front seal.

both ended up replacing converters and fixed it
 

thunder550

Active member
Apr 2, 2013
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You gotta have a hairline crack somewhere or warp, chris. I would change the bell housing.

While your in there, you might as well mod the converter flow valve to stop pressure drop and up the main line pressure.

Looks like I can get a new bellhousing for <200, so I think that's going to be my next move. Don't have it in me to pull the trans for the 3rd time just yet, so it might be a little while. Upper oil pan is still leaking too, so I'll do them both together whenever i get up the energy to tear it apart again. I'll look up the converter flow valve mod, might as well get something out of it for pulling the trans 3 times lol. Thanks James.

Between the aftermarket lower pan, the leaking upper pan, and the leaking trans housing I'm wondering if the previous owner nailed a rock or something with the oil pan and broke a bunch of stuff loose. Could all be tied together possibly.

I’ve seen a couple stock converters leak somewhere and thought it was a front seal.

both ended up replacing converters and fixed it

I can see that, the only thing about it that doesn't make sense is that the fluid is only on certain bolts, not next to each other, and fluid isn't spun around inside the housing...it's just it specific spots. Although with me buying the truck to be a tow rig specifically, maybe it would be worth it to swap the stock converter out for a towing one next time the trans comes out.
 
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PureHybrid

Isuzu Shakes IT
Feb 15, 2012
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Central OH
I can see why a stock converter wouldn't like higher pressure than stock, but why would the flow valve mod hurt it while at stock pressure? Will the converter not handle anything over the factory cut back?

TBH I did the flow valve mod on the last couple stockish rebuilds for the local wrecker shop, been running flawless for a few years now. Beginners luck?
 

thunder550

Active member
Apr 2, 2013
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Phoenix, AZ
When I replace the converter housing, would you guys replace the bolts as well? Part of me says that's dumb, but the other part of me would rather spend the money on new bolts than run the risk of having to pull the trans a 4th time.