Oil dripping around starter

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JT58

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I need some help diagnosing an oil leak in my 1987 Squarebody V10 with a 74 5.7 in it, SM 465 manual 4 speed. I have an oil leak, drips that originate around the starter dripping from both sides and flows down the protective plate at the bell housing and drips on the floor. I have looked all the way up the back of the block to the top of the engine to trace the leak, around the valve covers, all dry. Top of the engine is dry. It has a new rear main seal and oil pan installed by a shop 6 months ago. I just installed nice new valve covers and gaskets and that for sure is not the culprit, no change in the oil leak. Dry around the dip stick tube. Is there anything above the starter I cannot see that oil would be leaking from?

I have read other posts and some conclude it is the rear main. I would hope not as if it is, it will need to be done again. The shop that did it took 2 months, leaving the truck baking in the hot FL sun. I won't go back there again. I have found a better shop I will bring it to. But it for sure will suck paying another $2500 for something already done. (I could have a nice new engine for 5K). Hard to find good shops these days. I like doing my own work and usually do and usually results in a good job but pulling transfer, trans out is too big a job for me.
 

PrairieDrifter

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2500 seems high, but I don't take my stuff to shops hardly ever especially never my squares so I don't know. It sounds like rear main. If not it'll be valve covers, rear intake valley, or oil pressure sending unit. Those should be pretty visible though.
 

JKRamsey1991

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Back of the engine common sources of oil; rear main, oil pan, distributor, oil pressure port behind the intake manifold, valve cover.
Less common would be the cam tunnel plug in the back of the block and the intake manifold itself can have oil seep.

I would pop the inspection cover off the bottom of the bell housing and see if the oil is inside the bellhousing letting you know if its rear main/oil pan/cam plug etc
 

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I have a similar situation on my 1990 350. it is hard to see in that area, but I think it might be the dipstick tube at the block on mine. like you said, all above the area i can see is dry. and that's the one thing in that area that I just can't see all that well.
 

Buck69

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A fresh engine is always nice, but it will likely take a fair bit more time for a new engine swap than a pan and rear seal replacement. It would depend how complete your new engine is. You may want to check into that if it is a concern for you and wasn't included in the 5k price you were given.
 

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Put some of that dye in the oil and get a black light to pinpoint the leak.
 

JT58

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On your 350 you can replace rear main with engine in the truck by dropping oil pan.
This is interesting as the shop that did the rear main stated that they had to pull transfer case, tranny, etc. to do the rear main. It was leaking about the same as it is now but it needed a clutch so I had them do the rear main at the same time. It has a 74 block from a Chevelle or Monte Carlo though from the code on the engine block. It runs good and strong, uses no oil so it's a good 5.7. Regarding 2500 for the job, shops around where I live are hard to come by, very booked and charge a premium.
 

JT58

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I would pop the inspection cover off the bottom of the bell housing and see if the oil is inside the bellhousing letting you know if its rear main/oil pan/cam plug etc

This is good idea, I'll take the cover off and have a look. When the rear main was done the first time, it definitely came directly from this area- this time, it's around the starter.
 

squaredeal91

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This is interesting as the shop that did the rear main stated that they had to pull transfer case, tranny, etc. to do the rear main. It was leaking about the same as it is now but it needed a clutch so I had them do the rear main at the same time. It has a 74 block from a Chevelle or Monte Carlo though from the code on the engine block. It runs good and strong, uses no oil so it's a good 5.7. Regarding 2500 for the job, shops around where I live are hard to come by, very booked and charge a premium.
A 74 block would have a 2 piece rear main seal. Can be done without removing transmission. It's possible they didn't properly install it causing a premature leak?
 

JT58

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A 74 block would have a 2 piece rear main seal. Can be done without removing transmission. It's possible they didn't properly install it causing a premature leak?
It would not surprise me if it was not done properly. The guy who runs the shop is really knowledgeable although I am not sure all of the techs are a high caliber. And that it took 2 months to do the work. I initially tried the shop out to fix my dual gas tanks issue. It would only pull from one tank. It needed a new diverter valve, fuel pumps and entire wiring harness. Someone had been in there before and did not know what they were doing. They did a really good job so I gave them the clutch and rear main job. When I got it back it still leaked. So I brought it back and they said I needed a new oil pan. New high quality pan from Jeggs installed, got it back, it still leaked. Brought it back again and they re-tightened the oil pan bolts. Now it's leaking again from around the starter. Now the new clutch slave they put in appears to be leaking, I just ordered a new one and will put that in myself. I won't use that shop again.

Really good news that the drive train does not have to come out to replace the rear main that it is a 2 piece. I'm going to visit a new local shop on Friday to have them look at the truck and possibly to re-do the rear main.
 

Ricko1966

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Did you vent the nice new valve covers correctly? Common problem,no pcv no valve cover vent,no draft tube and you end up with oil leaks,that will not stop until everything is put back the way it belongs. And if your shop was baseing the rear main labor based on year of truck they were correct about transmission and transfer case needing to come out. My guess when they told you that they didn't know you had an earlier engine.
 
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JT58

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Did you vent the nice new valve covers correctly? Common problem,no pcv no valve cover vent,no draft tube and you end up with oil leaks,that will not stop until everything is put back the way it belongs. And if your shop was baseing the rear main labor based on year of truck they were correct about transmission and transfer case needing to come out. My guess when they told you that they didn't know you had an earlier engine.
Good point on the valve covers. I bought the correct valve covers for the year engine. They have 2 ports- actually three- one for PCV, one for breather and one for oil fill cap. There was a plug in the one for breather, I had to remove the plug and put in a grommet, then the breather. There are no leaks around the valve covers. I was thorough when I installed them, taking my time and cleaning all around them, making sure they seated properly on the gaskets, etc.

Yeah, the shop may have based the labor on an 87. When I brought it to them I pointed out that the engine may not be an 87 due to the heads/valve covers. I had not done research on the block VIN until after that. When I brought I back and they put a new oil pan on, they got the correct oil pan for an 74, I did ask them about that.
 

JT58

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I want to ask about oil capacity for the engine. When that shop filled it with oil, they put in 6 quarts. It showed full to the dipstick line. When I recently changed the oil I measured 6 quarts coming out of it. I was not sure what to put in so I would not over fill it. I put in a little over 5, the level comes to 5/8 the way up the dip stick. I don't know if over filling it would also cause an oil leak.

Thanks for the responses and help- you are all so very knowledgeable. I learn more about my truck every day. And I love and appreciate how easy it is to work on, all of the nuts and bolts even on the trim.
 

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I want to ask about oil capacity for the engine. When that shop filled it with oil, they put in 6 quarts. It showed full to the dipstick line. When I recently changed the oil I measured 6 quarts coming out of it. I was not sure what to put in so I would not over fill it. I put in a little over 5, the level comes to 5/8 the way up the dip stick. I don't know if over filling it would also cause an oil leak.

Thanks for the responses and help- you are all so very knowledgeable. I learn more about my truck every day. And I love and appreciate how easy it is to work on, all of the nuts and bolts even on the trim.
Never mind how much oil you actually poured in.. "5/8 the way up the stick" doesn't tell us anything about the actual oil level.. The dip stick is calibrated to indicate oil level.. Upper most mark indicates the full mark.. Next mark down is the "one qt low" mark.. Proper amount of oil is anything between these 2 marks..

The proper way to add oil after an oil change: Fill the oil filter and install it.. Add the remainder of 4 qts oil.. Start the engine and let it run a few minutes.. Shut it off and read the level on the stick.. Add just enough oil to bring the level to the aforementioned FULL mark.. Close the hood, you're done.....
 

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