Real time help - what are the 5 large plugs on the head's top?? (1 Viewer)

[landtank]

This thread makes me wonder how many times this has occurred to others - it must be rare, since we don't have other previous cases listed on the board - right?

actually right now i loose about a 1/4" in the coolant overflow tank every 10k miles. Gave up looking for any more external leaks as it's just too small an amount. I'l be having an oil analysis done soon on my extended life M1 and will ask them to look for coolant in the oil at that time. I wouldn't be surprised if I needed these seals as well.

 

[IdahoDoug]

Turns out to be a 14mm. I would have purchased one if I could find it, but nobody carries allen socket larger than 12. Borrowed a 14mm allen wrench and will use a pipe on the short side to torque it down. Anyone find a torque setting?

Rick,

What about a lesser level of Loctite? The reason I mention it is the plug is large diameter and that red will give it huge surface area and basically make it permanent. Allen heads are not known for being sturdy, so even a milder Loctite might be impossible to remove. With such a large thread surface area (well over an inch diameter threads), could I use a milder loctite and would it also hold up environmentally to an engine head? I ask this because it would be quite the bummer to find out some day I need that plug out for some head issue - from converting the truck to run on propane, to future head work. So I'd like to be able to get it out again.

Excellent tips on using a bolt backwards with a couple locked nuts - nice solution.

As for whether this has happened to others. I did some Googling last night and found a couple engines that are known for a similar head plug issue. Nissan 3.0 V6s have one on the front of the head behind the timing cover that does it, for instance. So, mine was clearly a fluke but had I paid someone else to diagnose and fix my "coolant leaking in oil" problem I'd be willing to bet I would have paid for:

1- A new head gasket.
2 - Extensive subsequent diagnosis including a complete engine teardown.
3 - A rental car for the weeks it would have taken to find this.

So, I wouldn't be worrying this is going to happen to you.

Keep your fingers crossed as I'm really not out of the woods yet. A week from tomorrow when the coolant has stabilized I'll be picking up a bottle of Bailey's and kicking back in front of the fire, but not yet.

DougM

 

[cruiserdan]

I can not find a torque spec. Our guys suggest "quite tight" and to use FIPG on the threads in addition to the new gaskets. We have not encountered this on 1FZ engines but sometimes in other engines, probably a function of the total number out there.

 

[Rich]

Another approach to dealing with the allen wrench problem is to buy the right size allen wrench, and cut off a bit from the long end and insert it into a 14 mm socket.

 

[Nomis]

We have not encountered this on 1FZ engines but sometimes in other engines, probably a function of the total number out there.

In other words Doug is one unlucky SOB

Sorry Doug, I really hope this was the culprit and solves your issue.

 

[landtank]

Doug the locktite is for the nut to bolt surface so the nut doesn't move on the bolt. Using 2 nuts on the bolt as Robbie suggests works well for tighteneing as that motion actually tightens the lower nut onto the other. But when truing to loosen the plug that motion will want to also loosen the nut on the bolt. That is why I suggested locktite on the nut cause that bitch ain't moving no way.

So to clearify it's on the threads of the bolt to the nut and not the nut's surface to the plug.

Hope this helps.

 

[landtank]

I'd like to give a great big mud solute to both CDan and IdahoDoug for each taking one for the team as having probably the two most obscure unwanted repairs under their belts.

 

[IdahoDoug]

Rick,

Gotcha. I'll be able to see tomorrow when I pull the plug to replace the gasket if Toyota put anything on it from the factory. I like the FIPG suggestion as torch heat can one day blast that out for loosening. Rick, it's funny that I was thinking the same a couple days ago as I paged through Dan's post on fixing his oil gallery plug. A couple of "off the map" failures if ever there were some. What is completely ironic is that if this proves to be the problem, I could actually make a case that I never suffered a head gasket failure!! I have a very strong suspicion that this was the issue all along, though clearly my head gasket was on its very, very last legs. I'll look forward to posting a picture of it as it's quite dramatic.

DougM

 

[Beowulf]

I'd like to give a great big mud solute to both CDan and IdahoDoug for each taking one for the team as having probably the two most obscure unwanted repairs under their belts.

Agreed. The good news is that we might also benefit from a HG video if we are lucky.

-B-

 

[Lockd97]

Rick,

I'll look forward to posting a picture of it as it's quite dramatic.

DougM

I'll look forward to seeing a pic too! Your multiple threads with no pictures
is killing me!!!!LOL

 

[IdahoDoug]

Yeah, I'm not adept at doing that picture thing. And last night the laptop's power supply crapped out so I just got done ordering a new one online. It's amazing how annoying it is to have to sit at a desk to surf MUD when you've been doing it from the deck, the garage, bedroom, etc wirelessly. Anyhow, the laptop's got the software on it to D/L pictures off our camera and it's down until Tuesday when the power supply gets here.

DougM

 

[Riley]

Agreed. The good news is that we might also benefit from a HG video if we are lucky.

-B-

Double agreed. This was some journey to watch (read) from a far. Sorry it happened to you Doug but at least it was to someone who had the smarts and guts to dig deep and work through it (touch wood).

I feel much more enlightened now.

 

[landtank]

I'm also interested in seeing that HG shot.

 

[honk]

9/16" fits 14mm

 

[John E Davies]

Doug, I am so happy to hear you found the leak. This firmly reinforces my conviction that a pressure tester is a must-have tool for the home mechanic. Since the area of the plug is bathed in oil, there were no telltale crusty stains, correct? Would there have been any other way to see the leak, other than the tester, or taking the head off and to an engine shop?

Personally I wouldn't bother with the other plugs - just fix the one that is leaking, let your sealer set overnight, and pressure test again before reinstalling the cams. I am sure you just have a weepy gasket, but there could be a hairline crack. The odds of any of the other plugs leaking is astronomically small IMHO.

Good luck, and post pics!

John

 

[IdahoDoug]

John,

Thanks - appreciate it. You're right the area is normally literally flowing with oil, so absolutely no traces at the leak. The plug location is even slightly elevated, so drops flow immediately away from the spot so that simply removing the valve cover and looking wouldn't pinpoint it. Only actually watching the drops appear and flow away from the plug got it. Since it's under the valve cover there's no way it could be seen without beginning the teardown and normally once someone's doing this they'd just keep on going. I'm fortunate I had time to think it through and elected to stop at the valve cover and pressure test.

Agree on the other plugs. If I find this one comes out normally when I finally get to put a wrench to it in a few hours (waiting for parts to arrive at 11), I'll consider pulling the others and replacing the gaskets. If it's a struggle to get it off, I have little desire to struggle with the other 4, taking the chance on bunging one up and getting it halfway out. Allen heads are not known for durability, so I'll make the call atop the engine.

At the moment, I'm going off for a 2 hr road bicycle ride to chill and breathe some sweet Idaho air...

DougM

 

[Rich]

I would suggest taking a very careful examination of the plug, gasket, and head and endeaver to determine the root cause of the leak. The defect could be soley due to installation, or could be a defective plug, gasket, or head.

Keep in mind that the same person installed each of the plugs, and most likely the gaskets and plugs all came from the same batch. The nature of mass production enables the replication of errors.

 

[IdahoDoug]

Ah, back from the bike ride. Nothing like 34 miles of winding country roads at 165 heart rate to clear your mind. Got a call midway through it that my parts are mistakenly on the way to Montana. Didn't order from Dan as they were going to be here a day faster and the truck's sitting (shakes head...).

Anyhow, gonna get some things done and might do a timed leak down on the leak so I can repeat it after the plug's installed and hopefully find zero leak down.

DougM

 

[firetruck41]

...Got a call midway through it that my parts are mistakenly on the way to Montana. Didn't order from Dan as they were going to be here a day faster and the truck's sitting (shakes head...).

That'll teach ya! Cdan uses his voodoo on those who try to "get around" him. Another good reason to buy from Cdan:
1. Help feed his dogs
2. He will use black magic to thwart you if you don't buy "American"

Glad to see you are getting this sorted without having to redo the HG

 

[IdahoDoug]

Ben,

Thanks - we'll see. Jury's still out until the fat Cruiser sings...

DougM