Thread: first start-leak from rear??????

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I broke in my cam today and noticed a little puddle of oil under the rear. I could see the drip coming from the bottom/front of the bellhousing.
Is this leak likely coming from the seal between the pan and the rear main in the back?
I used one of those re-useable blue pan gaskets because I thought it would be better. The directions said not to use any rtv except a little at the corners. I really don't want to have to take the whole thing back out again, any ideas???

Also, I have a 180 thermostat in it and the temp just kept going up until about 205 or so when I decided I had to shut it down. Basically I broke in the cam in 2-10 minute sessions because of the engine temp. Is this OK?

It's still pretty hard to start, it's ok once it's running; is this probably beause the timing needs to be dialed in better?

thanks

It runs hotter because you're not moving down the road with wind in the radiator and you're breaking in a new engine. 205 is not a problem if you have a pressurized system. My 'Vette fan doesn't even come on until the temp hits 225. Also, two 10-minute break-ins is not the same as one 20 minute. You may want to give it another 20 minute run.

If you're lucky, you may have a leak at the pan. If you're unlucky - the rear main seal. Or, it could be leaking out of the back of a valve cover, or around the distributor shaft. Look around and see what you find.

If it's an automatic, take the inspection plate off of the bellhousing and see what you can see.

More than once, I've found a rear leak to be caused by a less than perfect seal at the intake manifold/block interface. Look it over carefully before you tear into it.

Tyler, I reply'd to your email in case you didnt notice. John

If you are nervous about heat put a window fan in front of the rad. while its running in.

my first small block i built i forgot to put the cam plug in the back . that was more of a stream of oil though

I didn't rebuild the top and bottom end of the motor, I just swapped out a cam, so it isn't the cam plug.
I did have a box fan in front of the radiator, a powerful one too.

I've checked over the back of the engine, and it doesn't seem to be coming from the distributor or intake. I've looked it over pretty good, it's really weird because if it's coming from the rear main seal or pan gasket rear I would expect it to be all over the flywheel, but it isn't, it just drips from the bottom edge of the bellhousing.

If it was the rear main seal, and not the pan gasket, wouldn't it leak when I'm priming the engine and put pressure on the oiling system??
maybe I should try priming it for a really long time and see if anything leaks.

speaking of oil, I put 5 quarts in it. I think that's right for a 402 BB.

I just layed under the thing for 20 minutes with a flashlight and can't find any traces of an oil path leading down to that bell. It's like the bellhousing is producing oil or something. There is nothing at all under the valve covers or intake, the back of the block is perfectly dry. The only place I saw oil was a drip on one of the pan bolts. It was the second rear most bolt. I don't know how the oil is getting from the leak down to the edge of the bell and the ground.

i just read your post again and you said its hard to start and were wondering about the timing. i dont know why i didnt catch it before but if your timing is off too far which it sound like yours is because of the starting, it will run warm also. as for the oil leak, i would just run it for a while, maybe it will seal up if its the rear seal or the pan. i'm kinda optomistic about those kinda things

Use more "Hubba Bubba",,,,,Lol,,,Seriously though,,,it sounds like you have the timing a bit off,,,,hopefully the starter is not on it's way out,,,have you done a complete Draw test yet??
As for the leak,,,,run a socket on those bolts and give them a tweak,,,only a slight tweak mind you,,,,over tightening will cause more problems.
It could be the difference between,,cold motor,,,pan gasket,,,,and hot motor pan gasket,,,,,you may be leaking a tiny bit when it's cold,,,then stops when hot,,,tweaking usualy helps.

Or "Bazooka Joe"

the starter is fine, it cranks good. What I mean by tough to start is, when you crank it, it doesn't just fire up like a daily driver would, it will kind of cough a few times, a couple cylinders might fire a little, but it won't keep up. I have to just keep trying and eventually I'll get a good fire that gets it going permanently. I rotated the distributor a little bit to advance it slightly. I'll have to run it again today, and disturb my neighbors again since it's got open headers still, and see what I can find.

thanks for all the replies, I'll post my results

Vaccume .....Carburation.....Timing......maybee a bit of all three.
time to get the wrenches out and check carb bolts,,,,take a propane torch and while its running,,,turn the propane torch on,,unlitt,,,,,and send a little propane near your carb base plate,,and then your intake manifold to head join,,,,,if you notice a decent RPM difference,,then it may indicate,,,vaccume leak,,,near the point where the propane gets sucked in.
Dont do this for too long,,,,dont let propane build up,,let it disperse,,,,and go at it again.
Good luck

why do engines run hotter if the timing is retarded?
I would think it would be the opposite because you wouldn't have time for the full burn and maximum pressure.

it can go either way,,,advanced spark will give insufficient burn,,just like retarded spark,,,,it's a difference in where the heat is going to end up,,,,in your exhaust,,or your block.