RB26 Head Freeze Plug Size EMERGENCY!!!

[Beat92240]

I was attempting to finally fire up my car tonight. Unforunately I found that there was a left out freeze plug from the rebuild. Now that motor has been secured in a position that makes this plug nearly impossible to get to, I was hoping someone here could help out and let me know the size of the one I have in the yellow circle of this picture. It would help me save the time of trying to make multiple plugs work.




Thanks in advance.

[Carl H]

thats not a freeze plug...maybe a bolt hole but def not a plug.
the freeze plug would be the one under it.

[Beat92240]

Yeah we can't tell if its threaded or not. Needless to say its in the absolute worst position possible when its installed in the car. A thread would be nicer...so hopefully its something along those lines. Thank god you're back carl

[RRRRB]

is it leaking oil or anti freeze?

did the head have an oil drain fitted to the back of it at one point?

[Carl H]

might have to pull it out to fit a fix...else pull the head.
the former is easier than the latter.

[Beat92240]

It's actually water for sure. You can force it out when you squeeze the rad lines. So unfortunately (or fortunately) we know it's water.

We're hoping to just find out what it is...then probably blow a hole through the cabin side of the firewall behind the dash where the hole on the head is and plug it that way if it's a freeze plug type...if its something threaded I think I have enough room to get something in there, which is why I'm hoping it's threaded.

[Beat92240]

And never had an head drain as far as I can tell....

[Carl H]

drilling a hole in the firewall sounds like an awful lot of work, not to mention unsightly.
by the time the dash is out and hole drilled the motor could have been out and back in, but thats just my 2c.

[Beat92240]

Eh youve done a lot more work on RB's than me. Ive only put the motor in once. I've had the dash in and out on multiple occasions. So for me its a half hour job to pull the dash. I just personally feel a lot more comfortable doing it that way.

And Im doing the work at a car audio shop with a lot of spare grommets layin around so I'm going to plug the hole after its drilled. Its just unfortunate that it has to be done period. I may miss my tune date because of this since I'll be out of town all next week, and only have Monday, wednesday, and Friday of this week to get this fixed, get it started, get it aligned, exhaust put on, and inspected. Time is not on my side....

[jetdriver]

If the 26 head is similar to the 25, that hole should be the drain for the spark plug wells. It should be open. If you have coolant coming out there, you have bigger problems. Here is a picture of the 25 head for comparison.
http://i207.photobucket.com/albums/bb18 ... 008216.jpg

[gawdzilla]

^ uh oh that doesn't look good. that said, you might be mistaken about where the water is coming from. There are some hard water lines that run back there for the twins. maybe you crushed one on install, have a cracked line, or a loose rubber line back there and it just looks like it's coming from there. i'd pull the radiator and slide the motor forward a few inches and take a better look. don't need to yank it all the way out.

[Beat92240]

If the 26 head is similar to the 25, that hole should be the drain for the spark plug wells. It should be open. If you have coolant coming out there, you have bigger problems. Here is a picture of the 25 head for comparison.
http://i207.photobucket.com/albums/bb18 ... 008216.jpg

Yeah I agree that does not sound good at all. Unfortunately I know it was comin from there because I replaced the hard lines with AN's that are ran lower than where the water is. U can also hold a mirror back there and watch the water coming out of the hole. So unfortunately I'm very certain it was coming from there, which makes me sad. I'll have to investigate my plugs tonight.

That being said, what is this the drain for? Like if I pull the plugs youre saying I should see water? Or if I just pull the coilpacks there should be water in there?

[jetdriver]

I can't remember if it is line bored to all spark plug wells or just #6. Pull #6 coil and see if it is wet around the spark plug.

[Beat92240]

thanks for the help. Unfortunately it probably wont be a good outcome. and it meant i wasted all yesterday plugging that hole, but better you to tell me now than try starting it that way. I'll take a look at it tonight and let you know my findings.

[Carl H]

uh...there are no holes in the spark plug valley...anywhere.

[Shocker]

Easiest way to be able to get back there IMO would be to remove the rad, unbolt the trans, motor mounts and just slide the whole engine/trans assembly forward to the rad support. Should have ~ 4 inches of room then to work.

[Beat92240]

If the 26 head is similar to the 25, that hole should be the drain for the spark plug wells. It should be open. If you have coolant coming out there, you have bigger problems. Here is a picture of the 25 head for comparison.
http://i207.photobucket.com/albums/bb18 ... 008216.jpg

This is accurate for the 26 too. I pulled the coil packs and sho nuff, water in the number 5 spark plug well:

The water was pretty significant, enough to fill the spark plug well in that cylinder. You can also see the problem pretty clearly in the picture...There are 3 coolant plugs in the spark plug galley. The rear most being in the 5th spark plug well. This one was so loose I could freely turn it with my fingers. So I pulled the plug, through some sealant on it, snugged it back down, and sweapt the water out. Problem solved!

Guess this was a good learning experience for all if this ever randomly happens again. Thanks everyone for the help.

[Carl H]

wonder why that plug was loose, i've never seen anyone take it out even for head cleaning.

[Darius]

I'm confused now. How was coolant from the #5 spark plug well making its way to the hole in the back of the head?

[Beat92240]

wonder why that plug was loose, i've never seen anyone take it out even for head cleaning.

Thats exactly what the engine builders said. They didn't bother checking it out because they didn't loosen it. So must have been loose from the previous owner for some reason. And these guys have built multiple engines for me and I've known them for over 10 years, so they would have told me if they left it loose for some reason.

The motor was pretty beat in the past, which is why I was forced to rebuild it all. So who knows in what ways it was abused or messed up before I got it....

[Beat92240]

I'm confused now. How was coolant from the #5 spark plug well making its way to the hole in the back of the head?

Ya know I was wondering the same thing. There are no visible channels for the water to get from 5 to this drain hole...and 6 wasn't wet so it didn't overflow from 5 to 6 then to the hole. There may be some access cast behind the spark plugs (to the bottom in the picture, where the left side around the spark plug tube is lower than the right side). That's where it would seem to be with how the water seemed to be routing itself.

[Carl H]

atleast it was a simple fix...stupid to have to have fixed it but still, beats drilling thru the firewall.

[Beat92240]

no doubt...beats having a bad head gasket or something too. It was a pretty big relief. Now onto the next project of trying to locate a new Ignitor Chip by next saturday for my tune date....haha. Never ends!

[Carl H]

lol, if you dont mind repinning i have a few spares with me.

[Beat92240]

Pm'd you about it...thanks

[jetdriver]

If the 26 head is similar to the 25, that hole should be the drain for the spark plug wells. It should be open. If you have coolant coming out there, you have bigger problems. Here is a picture of the 25 head for comparison.
http://i207.photobucket.com/albums/bb18 ... 008216.jpg

This is accurate for the 26 too. I pulled the coil packs and sho nuff, water in the number 5 spark plug well:

The water was pretty significant, enough to fill the spark plug well in that cylinder. You can also see the problem pretty clearly in the picture...There are 3 coolant plugs in the spark plug galley. The rear most being in the 5th spark plug well. This one was so loose I could freely turn it with my fingers. So I pulled the plug, through some sealant on it, snugged it back down, and sweapt the water out. Problem solved!

Guess this was a good learning experience for all if this ever randomly happens again. Thanks everyone for the help.

You can see the drain left rear of #6 spark plug well. If the coolant plug was leaking it probably sprayed coolant over the wall between 5 & 6.