Cam lobe discoloration normal?

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71DodgeDemon340 said:
the leak started a few days after i shut it off, was leaking between the head and the intake on the front side
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yeah, I installed an intake and it was 20 degs in the garage. Leaked at the front corner, because the rtv didnt set. Turned it over before I caught the leak.
 
furrystump said:
yeah, I installed an intake and it was 20 degs in the garage. Leaked at the front corner, because the rtv didnt set. Turned it over before I caught the leak.
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Yeah im debating on doing it tonight or not, supposed to be 29 degrees. May wait until monday when it warms up
 
71DodgeDemon340 said:
Yeah im debating on doing it tonight or not, supposed to be 29 degrees. May wait until monday when it warms up
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RTV silicone is just that. Room Temperature Vulcanizing. That means at room temperature it will go off and get solid (relatively solid). If the ambient temperature is higher it will go off quicker. If it’s colder it will go off slower. But it eventually goes off. I can’t remember if it’s an endothermic, exothermic or some other thermic reaction. But it’s something like that.

The upshot is you can bolt the intake on and fire it up. The silicone will go off and set up quicker. It doesn’t need to sit for 24 hours before use.
 
Yes but if it’s cold and not set up then no oil or coolant should be getting on it. So you can’t fire up the engine to set it up.
 
413 said:
Yes but if it’s cold and not set up then no oil or coolant should be getting on it. So you can’t fire up the engine to set it up.
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I’ve fired up several engines below freezing and one was in the low teens. It had to get done. They all still run and don’t leak. You don’t have to wait.
 
Rat Bastid said:
I’ve fired up several engines below freezing and one was in the low teens. It had to get done. They all still run and don’t leak. You don’t have to wait.
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That's been my experience too. I can't think of a time that not waiting caused me a leak. Every leak leaked because I did a poor prep job, or there was a bigger issue (blow by).
The time to assembly has always been enough time for RTV to set for me.

IIRC, it's endothermic. Gets colder as it cures, but only slightly. Last engine I built, it was 10 degrees and getting colder each day. To be fair, it took me 2 days to get the engine in the car and fire it up for break-in. But when I redid the intake, it was maybe 20F out when I installed it and the thermostat and I fired it up right after I got the belts on it. No leaks, no problem.
 
Never had one leak before either, pulled it apart. Resealed and placed a small heater under the motor. Sealed fine second time.
 
Still waiting back from the engine builder so i can send him the pictures, do i have to check the lash? I thought with hydraulic lifters that was one benefit that you dont have to adjust it like you do on a solid lifter, again i am familiar with the operation and everything just havent messed with it
 
71DodgeDemon340 said:
Still waiting back from the engine builder so i can send him the pictures, do i have to check the lash? I thought with hydraulic lifters that was one benefit that you dont have to adjust it like you do on a solid lifter, again i am familiar with the operation and everything just havent messed with it
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No lash to set. You could check preload, but you probably don't need to. If it changed, it would be by the amount missing from a lobe or lifter, but your cam looks good.

Me, I'd pull the lifters one at a time after removing the rockers and check them. But it's not needed, just peace of mind.
 
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