leaking rear main seal?

[morepars]

What do you guys think - leaking rear main or continue forward???

I just got my 440 engine back from the builder. Was a complete build, they broke it in on a dyno. So now I am installing the motor, bell housing, clutch, 4 speed together into 74 roadrunner. It sits on the cherry picker at about a 45 degree angle as we slide it in. Natually it won't fit, the back of the bell housing hits the firewall, the 7 quart pan can't clear the K member, you name it. We try 3, 4 maybe 5 times - pull the torsion bars and cross members, beat in the firewall a bit, then a bit more. It's really close to dropping in, maybe a 1/4 of a inch for the oil pan to clear the K member.

Thats when we notice there are drips of oil off the bottom of the flywheel. Maybe 6 or so drops on the floor. Pull the motor out, drop everything off the block. Oil drips are on the motor side of the flywheel, seems to be coming from the crank. Does this seam normal, is it because of the angle on the hoist or maybe how long it was on the hoist, we were at it for several hours? You guys think it will be ok to continue, i.e. it should seal once installed and some more miles on the motor or does the motor need to go back to the builder for a new seal before continuing. I would really value your opinions on this one.

 

[moes]

First thing I would check is the pan bolts, did they loosen up from vibration on the dyno? I always use some blue thread fastener on my pan bolts to stop them from coming loose from vibration.

 

[NOSTRT980]

check cam plug for leak. the shop that did my block had it in on a slight slant causing a leak. had to pull it out thought it was a rear main seal leak, it wasn't.

 

[morepars]

First thing I would check is the pan bolts, did they loosen up from vibration on the dyno? I always use some blue thread fastener on my pan bolts to stop them from coming loose from vibration.

Great idea - I might be jumping to conclusion too soon. I'll use some leak trace to a large area and tip it back up to pinpoint for sure where leak is starting. Thanks guys!

 

[mopar 3 B]

Dont over tighten pan or valve cover gaskets if you do not want leaks.

 

[493 Mike]

What is the builders opinion?
Mike

 

[morepars]

Going back to the builder is the plan, if I need to. It took 15 months (2 month estimate) for them to rebuild it, I don't really want to begin that again unless necessary. I was mainly trying to improve my knowledge base before talking to them.

In the way of an update, I cleaned the oil off the block and then sprayed leak trace from the valve covers down past the cam plug, around the crank, down to the bottom back of the oil pan and rear oil pan bolts. Next, tilted the block to around 45 degrees and let it sit for 3 hours. No hint of a leak showed up anywhere. Dry as a bone.

With that I will call the builder Tue. I doubt they will say anything other than - Run it and see what happens, if it leaks bring it back in. I'll post where we end up.

I have found B Bodies Only to be a very accurate source of information for many years. If the concensus here was replace it, I was going to push hard for replacing the rear main before putting the drive train in.

 

[dvw]

Some aftermarket pans don't fully cover the openings for the rear main seal retainer bolts. If you don't fill the area above the bolt holes with RTV, oil can weep around the bolt recesses when the engine is tilted. Remove the flywheel and look carefully along the rear of the pan. Been down this trail before.
Doug

 

[Fran B]

Run oil pressure with a drill and leak trace before you take to builder.

 

[ksurfer2]

https://redirect.viglink.com/?format=go&jsonp=vglnk_152276927821413&key=ac712ab515bed570ccd30265c6785a84&libId=jfjti4ex01000bfs000DAein71caj&loc=https://www.forbbodiesonly.com/moparforum/threads/chasing-oil-leak.146272/#post-910888185&v=1&out=https://www.forabodiesonly.com/mopar/threads/oil-leak-detection-using-smoke-and-mirrors.386411/#post-1971767436&ref=https://www.forbbodiesonly.com/moparforum/account/likes?page=2&title=Chasing Oil Leak | For B Bodies Only Classic Mopar Forum&txt=https://www.forabodiesonly.com/mopa...ing-smoke-and-mirrors.386411/#post-1971767436

The suggestion in this link with the hair dryer worked brilliantly when I was chasing an oil leak in a valve cover. Maybe it would save you some time and effort as well.

 

[Fran B]

post #12 hair dryer

 

[morepars]

Run oil pressure with a drill and leak trace before you take to builder.

 

[morepars]

Thanks to all for the great replies. Tried them all without a trace of another leak. Builder says full steam ahead. They have a 3 yr warranty, so if it leaks right away, they will deal with it. Put the motor/trsnny in without any more leaks. We'll see what happens when I get it running.

 

[khryslerkid]

Thanks to all for the great replies. Tried them all without a trace of another leak. Builder says full steam ahead. They have a 3 yr warranty, so if it leaks right away, they will deal with it. Put the motor/trsnny in without any more leaks. We'll see what happens when I get it running.

It might be doing what dvw posted, #8.

I've been seeing this with my 440. I'll have the front end jacked up for awhile, let it down and the next day I get a drip or two. I've wiped it off and I'll never see it again until I have the front up again.

I'm pretty sure I didn't use any sealer on the seal retainer bolts so more than likely that what's happening. I'm not worried about it unless it gets worse.