- Thread starter
- #21
Water still runs through with oil cooler bypassed. Onto pulling the side inspection cover. Thank you.
Help! I may have cracked block/head/?
- Thread starter GJCruiser
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I had the same thing happen. Thought I blew a head gasket or cracked the block but after tearing everything down I found it was one of the head core plugs.
BEFORE you pull the head and do all the work like I did, pull the valve cover and the push rod cover then check to see if there is water coming out of any of the plugs.
Here was the plug that caused me so much grief.
BEFORE you pull the head and do all the work like I did, pull the valve cover and the push rod cover then check to see if there is water coming out of any of the plugs.
Here was the plug that caused me so much grief.
- Thread starter
- #25
BOBWhite74. Two learnings from your photo. The top of the head has plugs too, and your leak looks rather slow compared to what I'm expecting to see. I hope mine is easier to spot!
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- #26
Removed side inspection cover and freeze plugs looked intact. Added water to radiator and water started flowing down out of pushrod holes from above. Removed valve cover to observe the first three (in row from front to back) freeze plugs lying along side their holes as pictured below. Plugs, gasket, and FIPG on order from Mr. T.
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- #27
Does anyone have experience/an idea how I might reinstall the plugs with rocker shaft in place? The shaft is directly above the plug holes but high enough to make the angle slight. My guess is it depends on the required method to install the plugs. Does one drive the plugs from the edge working around, by driving the center, or by precision driving while matching the outside edge with something?
Take rocker shaft off, use proper sealer around outside, just a light/light smear around it, mainly for lube when going in. find appropriate sized driver, whack, maybe smooth the bore before to check for rusted/pitted spots, use a big hammer , something with enough weight to set the plug without multiple hits.
Again, pull the rockers. Find a socket that just fits inside the cup. Use a short extension and drive her home. They go in fairly easy…..I think someone above said sealant….yes, use something like aviation permatex, silicone gasket sealer, etc…
I think you got really lucky! I would use a small wire brush in a drill or Dremel to de-rust the inside of the port edges before installing the new plugs. I like aviation Permatex. I'm using a can from my dad's he bought in the 50's. It was the only thing that would seal the bleed nipples on my wheel cylinder so I could use my mighty-vac.
Pulling the rockers isn't a big deal, just remember to get install everything back the way it came out. I started mine the first time with the rocker cover off and made sure oil was getting through to all the passages.
Your right about my leak being slow compared to yours! I thought there might be a pinhole like mine but to see them popped out like that most likely means that there was some sort of freezing. Hopefully you don't have a crack somewhere!
Your right about my leak being slow compared to yours! I thought there might be a pinhole like mine but to see them popped out like that most likely means that there was some sort of freezing. Hopefully you don't have a crack somewhere!
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- #32
Yeah, I'm aware there may still be a crack. I was trying to short the procedure by saving pulling the rocker shaft and having to readjust the valve clearances. That's probably short thinking. I'll pull the rocker shaft and start over. Just didn't want to do the extra work to button it up and then find a crack.
Once you replace the the core plugs you can pressure test the system. Most big box a/p stores have a loan a tool program for a tester.
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- #34
I was aware of a loan a tool for plug installation. Many videos just use a socket. Is there a loan a tool option to pressure test? Thanks
Yes, it should look something like this. You can test with or without water. Without water your wanting it to hold a constant pressure. With water you can look for leaks. I use distilled water.
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- #37
I installed the core plugs today and followed up with a pressure test of the coolant system. Everything looked good. Had a very slow leak (about 1psi/hour) but couldn't find it. Filled radiator with water (it fills, no water in oil) and repeated pressure test. No seepage from any core plugs.
In photo below, note there is a small hole in block behind block core plug on driver's side under cylinder 5 or 6 (pretty far back). Not sure what that hole is for and what specs it may have. Started the 55 and she runs as well as she ever has. That low #2 compression reading from last week still sticks with me so I'll repeat that test in a day or two.
Anyone know the specs on that hole?
In photo below, note there is a small hole in block behind block core plug on driver's side under cylinder 5 or 6 (pretty far back). Not sure what that hole is for and what specs it may have. Started the 55 and she runs as well as she ever has. That low #2 compression reading from last week still sticks with me so I'll repeat that test in a day or two.
Anyone know the specs on that hole?
Get the engine warmed up. Pull the valve cover, start it up. I'd use a lead hammer and strike #2 valves in their line of action several times while they are closed, hard enough to pop them open and let the compression blow the sealing area clear. Then check your compression again. A leak down test lets you listen to see which valve is bad if its only one. If you need a valve job this will not fix it, but if its speck of a deposit it could very well solve the problem.
On my 74, that port is where my oil pressure sending unit lives. I'm not sure what specs a plug for that port would be, but better find something before you run it anymore.
- Thread starter
- #40
This is an early (1975) 2F. I'm reading that 1Fs and early 2Fs had their oil sender there? On my vehicle, the PO installed a mechanical oil pressure gauge in the oil cooler. Note---My leak from that hole is water though.
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