How can I tell if the block is cracked?
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From: Dale City, VA
Car: 91 GTA and 85 IROC
Engine: 355
Transmission: gear jammer
Axle/Gears: 4.11
How can I tell if the block is cracked?
w/o pulling it out of the car.
I think I may have a big problem. Car is leaking oil from the driver's side badly. I can't see where it's coming from. Is there a die or coloring I can add to the oil so I can find the leak?
I really don't want to buy another block considering the money I have tied up in the machine work for this one. Thanks in advance.
I think I may have a big problem. Car is leaking oil from the driver's side badly. I can't see where it's coming from. Is there a die or coloring I can add to the oil so I can find the leak? I really don't want to buy another block considering the money I have tied up in the machine work for this one. Thanks in advance.
Last edited by Free Bird; Nov 15, 2005 at 08:59 AM.
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From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
There's a UV dye kit available. Wash the engine off, add the dye and run up the engine. Using a UV light and special glasses, the source of the leak can be easily be detected.
Chances are with a cracked block you're going to have a coolant leak before you get an oil leak. I'd start with the rocker cover gaskets or the intake china wall seals.
Chances are with a cracked block you're going to have a coolant leak before you get an oil leak. I'd start with the rocker cover gaskets or the intake china wall seals.
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From: Dale City, VA
Car: 91 GTA and 85 IROC
Engine: 355
Transmission: gear jammer
Axle/Gears: 4.11
I've checked both valve cover and china walls. No mixing of coolant in the oil or oil in coolant. It looked almost like the oil seeped up through the outter bolt holes in the block. I've never seen anything like it. Where do you get the UV kit? Autozone? Advanced? Pep boys? Napa? Thanks for the reply, I'm starting to loose my mind here.
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From: Browns Town
Car: 86 Monte SS (730,$8D,G3,AP,4K,S_V4)
Engine: 406 Hyd Roller 236/242
Transmission: 700R4 HomeBrew, 2.4K stall
Axle/Gears: 3:73 Posi, 7.5 Soon to break
Try baby powder all over the place. Inexpensive alternative 
It will show where it is coming from. (dipstick hole ? to much case pressure)

It will show where it is coming from. (dipstick hole ? to much case pressure)
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From: Mercedes Norte, Heredia, Costa Rica
Car: 1984 Z28 Hardtop
Engine: 383 Carb
Transmission: 4L60
Axle/Gears: 3.54 Dana 44
Most of the oil passages are in the center of the block. Even if the block cracked it would be coolant that was leaking, not oil.
On the passenger side of the block the fuel pump mounting area and the famous "smog pump mounting hole" on the front of the block are open to the crankcase.
On the passenger side of the block the fuel pump mounting area and the famous "smog pump mounting hole" on the front of the block are open to the crankcase.
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From: Dale City, VA
Car: 91 GTA and 85 IROC
Engine: 355
Transmission: gear jammer
Axle/Gears: 4.11
Sorry guys it's leaking on the drivers side. I'll edit original post. Any word on where to get the UV leak test? Or can I just clean up the block and use the baby powder? Trending Topics
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From: Mercedes Norte, Heredia, Costa Rica
Car: 1984 Z28 Hardtop
Engine: 383 Carb
Transmission: 4L60
Axle/Gears: 3.54 Dana 44
Originally posted by Vader
You mean the old fuel pump push rod restraint bolt hole? That's always a good place to look.
You mean the old fuel pump push rod restraint bolt hole? That's always a good place to look.
Where on the drivers side is it leaking? From the front or the back of the block?
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From: Dale City, VA
Car: 91 GTA and 85 IROC
Engine: 355
Transmission: gear jammer
Axle/Gears: 4.11
It looks like the middle. Haven't checked the oil sending unit yet. It's not coming from the filter.
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From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Any good shop should have a UV tester. I don't think you would want to pay the price to buy one just to check one leak. They're not cheap.
Driver side leak is a lot different than passenger side. #1 check oil pressure sender or any pressure line for a mechanical gauge if you have one. Even Autometer oil pressure gauges come with that cheap plastic line. Upgrade to steel braid or copper if you have a mechanical gauge.
Driver side leak is a lot different than passenger side. #1 check oil pressure sender or any pressure line for a mechanical gauge if you have one. Even Autometer oil pressure gauges come with that cheap plastic line. Upgrade to steel braid or copper if you have a mechanical gauge.
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From: Dale City, VA
Car: 91 GTA and 85 IROC
Engine: 355
Transmission: gear jammer
Axle/Gears: 4.11
It's a zz4 block and I believe the only place for it to leak is the oil pressure sending unit. Thanks for all your help guys.
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