lost oil pressure during break in

[williamsGN]

Lost oil pressure 8 minutes into the break in on my new motor. Was running 1500-2k RPM, shop that has experience doing GN motors just rebuilt short block, inspected, mic'd and reinstalled oil pump. Primed the motor with the prime tool before starting. Ran with 70 PSI the first several minutes. Suddenly I hear a tapping sound at the front of the motor, more 'plasticy' , thought the intercooler fan was hitting something at first. Oil pres goes down to 0. Pulled the cam sensor and everything looks fine down 'the hole' - gears look fine on the sensor and front of the cam. Mild resistance when turning the oil pump with a screwdriver. Friend thought I might have popped one or both the plugs in the block behind the cam gear. Any thoughts really appreciated, 3 months of work, 8 minutes before something goes wrong :frown:

 

[steve hughes]

Pull the oil pan and see if the oil pump pickup tube fell off.

 

[87GNSteve]

Oil gallery plugs like your friend suggested would be my 1st suspicion, but you'll probably find them in the pan.

 

[TurboSpeed]

Ive had a galley plug blow out on me at that pres. If it is the plug, tap the block for some screw in plugs or get the press in and make sure the holes in the block are clean of oil and coat the plugs with a good sealant/glue that resist oil and sets up hard and your good to go.

 

[Chuck Leeper]

If you go the screw in route, BE SURE the plugs don't go in so deep they block the oil passage. At the same time, be sure they clear the timing gear, etc.
Ruggles made me some "special" plugs, when he did my machine work[LONG time ago!]..He turned them down on a lathe, to where they were about a 1/4-5/16" thick.
B4 you go tearing into the engine, cut the filter open. Got junk?..Don't waste your time w/ pan removal. Take it back out.

 

[Mad_Trbo]

Excellent Advice

If you go the screw in route, BE SURE the plugs don't go in so deep they block the oil passage. At the same time, be sure they clear the timing gear, etc.
Ruggles made me some "special" plugs, when he did my machine work[LONG time ago!]..He turned them down on a lathe, to where they were about a 1/4-5/16" thick.
B4 you go tearing into the engine, cut the filter open. Got junk?..Don't waste your time w/ pan removal. Take it back out.

A micrometer is your friend, excellent advice.

 

[forcedfedv6]

Yep cutting the filter is a good suggestion and if it is clean then pull the pan down and most likely the little plugs will be laying down there.. good luck.

 

[williamsGN]

I talked with the owner there and they are more than willing to help, as much as bring the car back and they'll wrench on it in the car !

He said in his 37 years they never had a problem with the plugs except on the Fords.... I mentioned while I knew nothing of these plugs or I would of had em tapped - several builders had said they are a common problem

He's checking the notes from the build and will be back to me soon.

 

[turboc87gn]

At that psi make sure you didnt blow the guts out if your oil filter also!!!! Especially if you were usin a cheapie for break in purposes!!! i had a friend chase a similar problem for a month took the motor out went thru it put it back in did the same thing after the second time figured out it was the filter!!!

 

[williamsGN]

AC PF52, same as I always used over the years and thats the pressure it would usually run on start up, if not higher

 

[turboc87gn]

Theres a thread around here somwhere that says ac and fram filters have went to the birds in the last few years might wanna rethink ur filter choice even if thats not the prob....I just bought a wix for mine..hope you find ur prob.....

 

[williamsGN]

I thought of going with the Mobile1 filters. Heard about the Frams years ago, and about the AC knockoffs at the auto stores. I always look down the filter to verify its quality when I pick up an AC.
http://www.turbobuick.com/forums/general-turbo-buick-tech/235897-ac-delco-oil-filter-shedding.html

 

[gnxtc2]

If you go the screw in route, BE SURE the plugs don't go in so deep they block the oil passage. At the same time, be sure they clear the timing gear, etc.
Ruggles made me some "special" plugs, when he did my machine work[LONG time ago!]..He turned them down on a lathe, to where they were about a 1/4-5/16" thick.
B4 you go tearing into the engine, cut the filter open. Got junk?..Don't waste your time w/ pan removal. Take it back out.

TA sells the correct "depth" plugs

Billy T.
gnxtc2@aol.com

 

[williamsGN]

Cut apart the filter, looked fine - no debris. If it ends up being a galley plug, can you tap in the screw type with the motor in the car ? What would cause the tapping sound from the front cover ?

 

[dank GN]

pull the front cover and take a look

 

[williamsGN]

pull the front cover and take a look

Yeah, thats an easy job, almost as easy as putting in your new govenor

 

[Chuck Leeper]

My $.02..

Cut apart the filter, looked fine - no debris. If it ends up being a galley plug, can you tap in the screw type with the motor in the car ? What would cause the tapping sound from the front cover ?

Short answer: no.
Just 1 chip falls down into the galley, and a bearing takes a big "hit".

 

[87GNSteve]

Long answer: maybe
I have done it, same situation fresh rebuild plug popped out. I put grease on the flutes of the tap to catch the chips had a magnet, white rags. Resist the temptation to use compressed air and brake cleaner to blast the chips they will send it INTO the block.
I kept cleaning the hole with my finger in the rag and grease until it came out clean. Then solvent on the rag same steps. If you are careful you can pull it off. I did gamble but I worked in a engine machine shop for years before and it wasn't my first rodeo.
The other option is;install the plug and stake it. Get a pointed punch and hit it at the "8 points of the compass" around the casting approx 3/16 from the edge of the plug this will put added pressure on the ID of the plug hole. Strike at opposite sides N- S -E -W etc.
I do prefer the tapped plug.

 

[Mad_Trbo]

Plug Tap

Long answer: maybe
I have done it, same situation fresh rebuild plug popped out. I put grease on the flutes of the tap to catch the chips had a magnet, white rags. Resist the temptation to use compressed air and brake cleaner to blast the chips they will send it INTO the block.
I kept cleaning the hole with my finger in the rag and grease until it came out clean. Then solvent on the rag same steps. If you are careful you can pull it off. I did gamble but I worked in a engine machine shop for years before and it wasn't my first rodeo.
The other option is;install the plug and stake it. Get a pointed punch and hit it at the "8 points of the compass" around the casting approx 3/16 from the edge of the plug this will put added pressure on the ID of the plug hole. Strike at opposite sides N- S -E -W etc.
I do prefer the tapped plug.

Tap best way to go if the block has not been final cleaned.

Staking best route to go unless you have been to the rodeo a few times. Not worth the gamble when this will get the job done just fine with little to no risk! Risk reward isn't there.

Wait till the next rebuild to tap and take this as a small lesson learned.

 

[TurboSpeed]

Get yourself a good shopvac , get a funnel and modify it to go on the end of the shopvac hose, place it were you will be tapping, grab someone to hold the shopvac hose in place, now get a osg high spirl tap. it will bring the chips out of the hole, and the vac. will suck up the chips.