Hello everyone,
Looking for some advice. I redid my cooling system and I've been chasing a intermittent leak near the bypass pipe. I replace the bypass #1 the first time, but didnt use any rubber grease so the theory was that the o-ring because dislodged. I took it apart, lubed, put it back together easily. It still leaked, but intermittently. At first it leaked for a day, then went away for 2. Then it leaked a little. Then once it leaked a lot for just running about a minute.
So I assumed the bypass pipe had a hairline crack, so I replaced it, new o-rings, lighter on the grease this time. I also replaced the thermostat housing gasket and heater pipe gasket. Everything is torqued to 15 ft lb. So I bleed the system, no leak. I let it cap it - let it idle and drive in the neighborhood. No leak. I do a quick errand and she leaked a little over the course of 3 miles (round trip). I use compressed air to dry the area, start the truck and cannot see any leak. I let it idle and I rev it, and iddle, and rev and after 10 minutes...nothing. So I drive it, thinking I'm not working the system hard enough. I check it several times. Nothing. I've never heard of a leak that goes away. Is it maybe needing the burn the toyota rubber grease off to seal effectively? Very open to suggestions here.
EDIT: I finally got a glimpse of where the leak is coming from, coolant came from inside the bypass pipe - where bypass #1 is located. I've already replaced the o-rings there twice, and the new bypass tube #1, and the bypass pipe. The inside of the thermostat housing doesnt look pitted, but Im going to take it apart for the third time and see what I can discover. I will say, I thought the bypass #1 went into the housings too easily.
New bypass pipe 1635166010
New water bypass #1 1626866010
New o-rings (3) 9030129006
New thermostat
New thermostat housing gasket1611966020
New gasket for heater tube1578566010
Looking for some advice. I redid my cooling system and I've been chasing a intermittent leak near the bypass pipe. I replace the bypass #1 the first time, but didnt use any rubber grease so the theory was that the o-ring because dislodged. I took it apart, lubed, put it back together easily. It still leaked, but intermittently. At first it leaked for a day, then went away for 2. Then it leaked a little. Then once it leaked a lot for just running about a minute.
So I assumed the bypass pipe had a hairline crack, so I replaced it, new o-rings, lighter on the grease this time. I also replaced the thermostat housing gasket and heater pipe gasket. Everything is torqued to 15 ft lb. So I bleed the system, no leak. I let it cap it - let it idle and drive in the neighborhood. No leak. I do a quick errand and she leaked a little over the course of 3 miles (round trip). I use compressed air to dry the area, start the truck and cannot see any leak. I let it idle and I rev it, and iddle, and rev and after 10 minutes...nothing. So I drive it, thinking I'm not working the system hard enough. I check it several times. Nothing. I've never heard of a leak that goes away. Is it maybe needing the burn the toyota rubber grease off to seal effectively? Very open to suggestions here.
EDIT: I finally got a glimpse of where the leak is coming from, coolant came from inside the bypass pipe - where bypass #1 is located. I've already replaced the o-rings there twice, and the new bypass tube #1, and the bypass pipe. The inside of the thermostat housing doesnt look pitted, but Im going to take it apart for the third time and see what I can discover. I will say, I thought the bypass #1 went into the housings too easily.
New bypass pipe 1635166010
New water bypass #1 1626866010
New o-rings (3) 9030129006
New thermostat
New thermostat housing gasket1611966020
New gasket for heater tube1578566010
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