Author Topic: Name that fluid?  (Read 4252 times)

Offline Mmeecchhee

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Name that fluid?
« on: March 31, 2015, 08:01:42 pm »
Got a leak that I cant seem to pinpoint.  '83 K10 manual trans.  I've been under the truck quite a bit trying to locate the origin of this leak.  At first I thought it was the trans, but then it seemed to look like it may have been leaking out of the valve cover.  Went through and checked all the valve cover bolts, they were good.  Ive got 80/90 in the trans, unfortunately if it was an automatic I would be able to easily distinguish between the fluids.  It looks as though its coming from somewhere on top of the bell housing and running down both behind the oil pan and where the bell housing mates to the trans.   Anyone know where this might be coming from, or any other places I can check? Any advice would be greatly appreciated.

Online Captkaos

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Re: Name that fluid?
« Reply #1 on: March 31, 2015, 08:33:09 pm »
Is it engine oil or gear oil? 
Just because the valve cover bolts are not loose doesn't mean they aren't leaking.  In fact if they are too tight it could cause them to leak.

Offline Mmeecchhee

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Re: Name that fluid?
« Reply #2 on: March 31, 2015, 09:05:34 pm »
I can't tell if its engine oil or gear oil.  I've checked the back of the heads quite a few times and they seem to be dry.  The heads and valve cover gaskets are pretty new, <6 months old.   

Offline FlatBlack77

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Re: Name that fluid?
« Reply #3 on: March 31, 2015, 10:16:42 pm »
could be the very back of the valve covers, the rear of the intake manifold, or the distributor gasket. probably could be a few other things too lol
"When you are a hammer, everything looks like a nail"
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Offline sbx22

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Re: Name that fluid?
« Reply #4 on: March 31, 2015, 10:47:32 pm »
I don't know what oil that would be but something to else to look at is tighten up the oil pressure line that is back there behind the valve cover on the driver's side.

Offline Mmeecchhee

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Re: Name that fluid?
« Reply #5 on: April 01, 2015, 07:07:26 am »
Anyone got any better ideas on how to pinpoint the leak?  Right now i'm just cleaning everything the best I can under there, driving it up the road and back then climbing under to see what I can see.  Nothing leaks when its idling in the yard. but it does when I drive it.

Offline roger97338

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Re: Name that fluid?
« Reply #6 on: April 01, 2015, 10:16:29 am »
There is a fluorescent dye that you can add to oil, then use a black light to see where the leak originates. I'm sure it isn't cheap. A quick search of google, bing, or yahoo should produce several companies that sell dyes for automotive fluid leak detection.