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Author Topic:   Leaking Rear main on "new" 400
BrianW
Dirt Freak

Total posts: 385
posted May 22, 2005 05:22 PM  
Ok - got the engine installed in the car, broke it in and there was a little drip from the rear - pulled the pan and it looked like the rear 'half moon' seal was leaking a bit - siliconed it up and it seemed OK, took some hot-laps and it all felt good, noticed a little drip, but a lot better. Went out for the heats and it "sprayed" about 2 qts of oil all over and got black-flagged from the smoke (thank goodness - don't want to blow this one up!) - am using the FelPro 2909 rear main and it's got to be leaking - Any thoughts? Tricks? The "big" side goes in towards the engine right?

49mtmod
Dirt Maniac

Total posts: 127
posted May 22, 2005 05:33 PM  
We had the same problem with a 406. We found out that there are different rear main seals we had the wrong one installed. Once we got the correct one the problem was solved. Sorry, but don't have the part #s of the seal we ended up using.

[This message has been edited by 49mtmod (edited May 22, 2005).]

JohnG
Dirt Maniac

Total posts: 137
posted May 22, 2005 05:38 PM  
If its line honed you need a oversized seal.

fel pro now sells you a normal seal with a shim that you put behind it thats in two pieces.

the shim is the same thickness as a zip tie.

just cut two pieces to fit behind the seal halfs and youll be good to go.


BrianW
Dirt Freak

Total posts: 385
posted May 22, 2005 09:28 PM  
Well, the machine shop said to use the #2909 seal which is for a line-bored 400 and not the one with the gasket set - guess I'll try the zip-tie behind the seal and see if that helps - can't hurt at this point the thing isn't going anywhere with it leaking like it is. Do you think that the current seal is OK and all I need to do is "shim" it in a little bit? Should I use some silicone on the seal when putting it in? I'm planning on just sliding the seal around the crank and not actually removing the crank if I can (since I can do that while it's in the car...)

Anyone know the right part number for the seal with the spacer provided?

BrianW
Dirt Freak

Total posts: 385
posted May 23, 2005 03:02 PM  
Ok - was thinking about the zip-tie behind the seal - does anyone think it would get hot enought to melt the zip-tie? Other options? I was thinking of using a piece of gasket material cut to fit in the groove, glue it in and leave it a little long then cut it once the seal is in the top so that it seals well. Thougts on that idea??

TEAMPCR
Dirt Freak

Total posts: 238
posted May 23, 2005 03:08 PM  
Don't want to sound like an *******, but I know how much I put into my engines, (not much in comparison to other guys, but alot to me).....Take the time and get the right seal. JMO Dave

samiller
Dirt Roller

Total posts: 14
posted May 23, 2005 07:50 PM  
if you line seal halves to block and cap. try move ends of seal halves so they don't line up where block and cap meet.

BrianW
Dirt Freak

Total posts: 385
posted May 23, 2005 10:17 PM  
quote:
Originally posted by TEAMPCR:
Don't want to sound like an *******, but I know how much I put into my engines, (not much in comparison to other guys, but alot to me).....Take the time and get the right seal. JMO Dave

I can't find any other seal reference for the 400 but the FelPro 2909 number that's in it. If I could find the right seal then I'd be glad to get it, but at this point the local shops only say that number and the parts stores are only listing the stock seal - they don't even list the 2909 as an option... Anyone that has the number please let me know - I'd rather spend the $20 on the right seal and get it done, but at this point I want to get back out and try something for this weekend...


NJantz
Dirt Forum Champ
Total posts: 755
posted May 24, 2005 06:09 AM  
Have u looked on FelPro's website?

TEAMPCR
Dirt Freak

Total posts: 238
posted May 24, 2005 06:27 AM  
Sorry, BrianW. My reading comprehension isn't always the best. My apoligies for sounding like an *******. I'll check with some "experts" I know and see if I can find anything out. Dave

52mod
Dirt Roller

Total posts: 11
posted May 24, 2005 07:36 AM  
Check and see if the seals are installed in the right direction. Remember the large lip side goes inwards.

Tim Weiss
Dirt Forum Racer

Total posts: 88
posted May 26, 2005 02:44 PM  
we had oil pouring out of the rear seal of our brand new engine zip ties fixed it just fine

JohnG
Dirt Maniac

Total posts: 137
posted May 28, 2005 05:15 AM  
the correct seal is available from Fel pro, just like I said above it has a shim in the package and a stock seal.

why waste extra money??

the zip tie doesnt get too hot it works just fine. I also silicone the back of it but it probably doesnt do anything.

engineman
Dirt Full Roller

Total posts: 55
posted June 13, 2005 03:27 AM  
The Zip-tie trick works great, use it all the time, havent had one leak yet....and I too put some RTV under it.
Just Shim it with a Zip-tie and never look back!

------------------
Mark's Racing Engines

(903)883-0196

www.northtexasracing.com

engineman@northtexasracing.com

BrianW
Dirt Freak

Total posts: 385
posted June 13, 2005 05:31 AM  
Thanks to all - it looks like it's fixed - the FelPro 2909 and some silicone did it. we'll see this friday when I can get it on the track. Glad that one is behind me!

dode
Dirt Forum Champ
Total posts: 613
posted June 13, 2005 09:47 AM  
Brian-

Might be good or bad that you weren't out there on Friday. I think there were only like 11 cars left at the end of the mod feature! I dunno what's happened, but since we started out there like two years ago I think the number of cautions each night has quadrupled.

John

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