Odd place for coolant to come out of (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Joined
Jan 19, 2019
Threads
6
Messages
78
Location
San Luis Obispo
Hi, I searched on here and Google and cannot find what the hole in the picture is for and why it is directly connected to a coolant passage. It leaks coolant once you fill it up to that level and if you blow air in it you can hear it in the radiator. It seams to be threaded but the head doesn't give it a seating surface if it were a gasket-ed plug or something. Maybe it is a taper thread. Inside the hole you can see the head bolt. So the hole is cross drilled right into the head bolt hole on the head. It seams very intentional so I don't think it is a weird rust hole which seams unlikely. BTW, this is a complete engine freshen up and when I had the head off and was cleaning it, I noticed this hole and it was filled with crud that I was able to chip away at until clear. This should have been a clue to investigate what it was for when I had it apart but I didn't.

Any ideas. This is located right behind the coil.

IMG_3341.jpg
 
Hi, I searched on here and Google and cannot find what the hole in the picture is for and why it is directly connected to a coolant passage. It leaks coolant once you fill it up to that level and if you blow air in it you can hear it in the radiator. It seams to be threaded but the head doesn't give it a seating surface if it were a gasket-ed plug or something. Maybe it is a taper thread. Inside the hole you can see the head bolt. So the hole is cross drilled right into the head bolt hole on the head. It seams very intentional so I don't think it is a weird rust hole which seams unlikely. BTW, this is a complete engine freshen up and when I had the head off and was cleaning it, I noticed this hole and it was filled with crud that I was able to chip away at until clear. This should have been a clue to investigate what it was for when I had it apart but I didn't.

Any ideas. This is located right behind the coil.

View attachment 2265662


do u have a plug like this facing towards the fire wall

NOT towards the front of the engine ?





this is Your OIL, GALLEY Plug ,

however i have Never seen one personaly facing the front of the engine bay

nor Leaking Coolant either ?


maybe :

@cruisermatt
@OSS
@Living in the Past
@4Cruisers
or
@Spike Strip

will have the 411 on this unique photo ?

These folks , are the 60 Series JEDI's in my opinion , one or more with have the diagnosis and a repair remedy for you thats By the FSM BOOK !


1586402831449.png



hang tight .......
 
Since I posted I have found links on the oil galley fix. It happens to be the same head bolt hole. You can see in my photo to the left of the hole is the location of your oil galley plug repair. I'm wondering if I have 2 things going on. 1. a PO drilled and plugged that hole maybe thinking that is where the oil galley plug should be drilled and tapped (?) 2. my Felpro head gasket isn't sealing the nearby block to head coolant passage and it is leaking into the bolt hole. When the head was off I did confirm the head bolt holes in the block are blind holes so no coolant is leaking up through the threads.
 
What is the Casting # on the head? (where this representative pic says 61030)

1586404245918.png
 
That's a '74 F1.5 head. I don't know if that hole is from factory or not. It's a transition engine only made one year.... Others more familiar with it will chime in...
 
does the hole go deep enough to the head bolt?
my WAG is a headgasket issue, I don't think any of the headbolts are surrounded/encased by coolant.
seems the hole is the path of least resistance for the coolant to escape.
is there a gap between the washer and the head of the headbolt?
 
My 74 with the F.5 has the same casting number as yours but I have no hole there.
Do you have a galley plug where it typically is?

F.5 Head 4.jpg


Here's a pic of the oil passage from head bolt to rocker tower, hence the galley plug for machining.

F.5 Head 2.jpg
 
You guys are great and have lead me in the right direction for things on here to search for. I looked at dozens of photos of different years of blocks, heads and head gaskets. Seems someone put a F1.5 head on the original F block. BTW I don't think I mentioned this is a but the 40 is 11/1970 and engine number is F 333 022. I think I may have the wrong head gasket since from photos it appears my engine has a coolant passage in the block where the F1.5 and F2 engines have an oil passage. So in my case the head Felpro gasket might be more of a universal fit POS (?) and joins my coolant passage on the block with the head bolt oil passage to the rocker arms on my F1.5 head. I think I just have to take it apart to find out. unfortunately.

For the head gasket, I keep reading in older post to use a Toyota gasket but it looks like they are discontinued now. Who sells a good gasket that is engine generation specific without combining holes generic fit
 
Try Mark at Mark's Off Road for the correct gasket/s.

818-953-9230

@65swb45
 
I found these photo comparisons from a long ago post. I hope it is OK to copy and reuse photos on here. If not let me know and I will remove it. Wrong head gasket from Felpro seems the most likely. I will keep you posted if so.

Head Gasket Compare.PNG
 
I'm pretty certain that coolant doesn't flow through that hole that you're pointing to in the top pic.
I have the keyhole shaped hole in my gasket (F.5). On there 20 yrs and no mix of oil and coolant. It was oem 11115-60033 NLA.
I remember so well because the first gasket came from Napa. It did not have the keyhole and I got no oil to my rocker assembly. Pulled the head again and got the oem.
Check out the pic on post # 167 of this "LINK" by MadMace. You can see a bit of rust around all the coolant passages but not at the hole in question.
I have a recently ordered non oem made in Japan gasket for my F.5 on the shelf and it has the keyhole shaped hole.
 
Now that I think about it, I believe the oil comes up out of that hole from a cam bearing and travels over to the head bolt via the keyhole and then up and over the rocker tower. I'm guessing you'll won't find a matching hole in the head.
Can't be certain on this but I'll bet a :beer: on it.
 
Last edited:
Now that I think about it, I believe the oil comes up out of that hole from a cam bearing and travels over to the head bolt via the keyhole and then up and over the rocker tower. I guessing you'll won't find a matching hole in the head.
Can't be certain on this but I'll bet a :beer: on it.
Not on an F engine. The rockers on an F engine get oiled from a tube that runs from the lifter area originating from the oil pump through the cam and up through the head and connects to the rocker shaft. Different from the eternally feed as you describe from an oil hole in the block through the oblong hole in the HG and up through the head bolt then through the drilled oil passage in the head and up into the rockers. I know for certain that this hole in the block is a coolant passage on an F engine because I spent a lot of time spraying water and air into all the coolant holes to flush and you can see the water exit the block coolant drain plug and freeze plugs. Also I dug out my old HG from the trash and discovered there isn't even a hole there (coolant passage F engine or oil passage F1.5 or F2) nor one on the head either. I am at stopping point waiting for a now until I get my HG from SOR. One more piece of info, this wasn't an issue before taking it apart. It ran really well not coolant escape. I even ran it without oil pressure (Dizzy not seated into pump). That's why I took it apart and took the while I am here I might as well do this, that and the other approach. Nothing even looked that bad. Slight grooves in the bearings and my cam looked not to sketch and definitely usable but I replaced it anyway. Everything is so darn expensive for these engines but I am nostalgic so I did not want to go the cheap route SBC.
 
Ah! My confusion. I thought it was established you had an F.5. So it must be an F.5 head on an F?
 
Ah! My confusion. I thought it was established you had an F.5. So it must be an F.5 head on an F?
Sorry no your right, I am learning about the possible ways this has failed bits at a time so in my first post I didn't have all my vehicle details. PO must have put on the F.5 head for reason unknown. The block is F and needs a F gasket which I am 99% sure wasn't provided in my Felpro kit. Also before I continue to bash Felpro, I should first check to see I ordered the correct part number. This may be all on me.
 
Last edited:
I just figured out why the hole was put there. It is threaded and I would bet it is a tapered thread. At one point a PO probably tapped into that oil passage so they could use the newer style rockers. Somewhere on here I read somebody bought a FJ and a PO had an oil feed line going through the valve cover. Apparently in the day this was a mid west repair.
 

Users who are viewing this thread

Back
Top Bottom