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Coolant Pipe Bolt Hole Stripped! 850 Topic is solved

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Dmck
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Re: Coolant Pipe Bolt Hole Stripped! 850

Post by Dmck » Wed Jul 11, 2018 1:55 am

Apologies, I stopped getting the emails for this thread so I didn't know there were more responses.

I tapped the hole tonight.

I went to Home Depot and got a 8mm 1.25 tap and drill set. The drill bit was an H but did not have a hex bottom. I also bought an 8mm x 1.25 25mm bolt to match the tap and length of original 7mm x 1.0 25mm bolt.

I also bought a 11" flexible shaft bit extension. (I bought the angle drill adapter but it was going to be to hard to keep it place for the task)

The flexible shaft had a magnetic hex hole so I bought a few different drill bits specifically for this. I bought a 17/64, 9/32, 5/16.

I first cleared out the hole using the 17/64 and used the original bolt length to know the depth to put the sharpie mark.

Then just to expand just the coolant pipes hole I drilled it out 9/32. After that I pulled out the 5/16 and it kept jamming in the hole, so I had to take my time getting the drill up to speed before inserting slowly and not letting the bit fly into it.

After that I was able to get tap into the coolant pipe without having to tap that because the hole was big.

I made sure to mark the tap with sharpie and tapped hole.

After tapping i tested bolt and it held. I then placed top bolt in and tightened down.

After tightening I was still getting a coolant leak! So I tried tightening a little more and little more, until I just didn't feel comfortable tightening any farther. Still a coolant leak!

The original bolt had a much wider base on it than the new one so that may be the issue. I'm going to go to the bolt/nut store here in town and see if I can find one.

If that bolt doesn't work or I can't find the specific bolt needed (an 8mm x 1.25 x 25mm w/ wide washer like base) then I will try gaskets.

I have a question about these coolant gaskets here are my options, what route would you take.

1) keep old gasket in and try to add another on top.

2) somehow get old gasket off (with very limited space) and shimmy in two gaskets

The coolant flow is happening in the middle of the coolant pipe connection (in between the upper and lower bolts) so it's not an issue with the tapped hole leaking itself.

I'm thinking it's possible that drilling the hole broke the gasket off its sealed mark and isn't as flush and lined up as it should be.

If I'm super lucky I will go out tomorrow and the gasket will have dried out and made a better seal and will have stopped leaking... (doubtful)

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Re: Coolant Pipe Bolt Hole Stripped! 850

Post by SuperHerman » Wed Jul 11, 2018 6:25 pm

I vote new gasket and a washer on the new bolt hole. Excellent work by the way.

I use a paper punch to enlarge holes or if I make the gasket myself (also an option).

Just clean it all up well and skip the sealant.

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Re: Coolant Pipe Bolt Hole Stripped! 850

Post by Dmck » Wed Jul 11, 2018 6:42 pm

SuperHerman wrote:
Wed Jul 11, 2018 6:25 pm
I vote new gasket and a washer on the new bolt hole. Excellent work by the way.

I use a paper punch to enlarge holes or if I make the gasket myself (also an option).

Just clean it all up well and skip the sealant.
Hi SuperHerman,

Have you ever replaced this gasket without removing the coolant pipe or head before?

Do you think me using two gaskets instead of one is a bad call?

What do you use for making the gaskets?

Thanks

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Re: Coolant Pipe Bolt Hole Stripped! 850

Post by SuperHerman » Thu Jul 12, 2018 1:11 am

I looked back at your pictures and realized the beast of the job you have undertaken. I now realize you had the head on - the picture I focused on was pre-head install - I didn't focus on the other pictures with respect to the gasket.

To answer your question - yes I have, but I avoid using sealants which makes matters worse in your case. I see your problem.

How much space can you open up between the pipe and head? Can you get a nice wide paint scrapper blade in there to clean off the old gasket and sealant (those flat 3 inch blades)?

What I do is use a small screw driver in the easiest to access hole (usually the one on the outside) and then push in the gasket when I think the screw driver will go through the hole. This fixes one end. From there I swing the other end up and try to get the bolt in a few threads. Then I square up the screw driver so the hole is centered and either tighten up the other bolt so the gasket stays or push the pipe in and pull the screw driver out and put the second bolt in. It is way easier to write about than to do. Sometimes it is easy and sometimes it is a beast.

Without knowing what the gasket looks like it is hard to tell why it is leaking - so I don't know if a second gasket will help.

That said, I buy generic gasket stock (you can get it at most auto part stores) that is suitable for coolant. I then trace what I need, cut with a scissors, razor blade and paper hole punch to size. If you go this route - it would not hurt to cut out two gaskets and try your idea.

Next question - how hard is it to remove the coolant line or at least loosen it enough so you have a good look and working space?

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Re: Coolant Pipe Bolt Hole Stripped! 850

Post by Dmck » Wed Jul 18, 2018 7:56 pm

Complete failure...

After an 3 hour long process of getting a new gasket in between the coolant pipe and the head, I have the exact same leak...

I tightened the bolts to the extreme.

What I plan to do next is a Hail Mary and I wanted to hear what you guys have to say.

I am going to turn on the car and let it run till hot, then drain the hot coolant. Then unbolt the coolant pipe and pry a space inbetween it and the head, while it's all still hot. Then inject anaerobic sealant in between the coolant pipe and head.. bolt back down and give a chance for anaerobic sealant to seal with heated engine. If I try to seal it with any sort of anaerobic sealant the coolant pressure will blow it out before heat could seal it, that's why I want to try this method.

Is there some specific sealant you would use other than anaerobic to do this?

If you replaced the gasket and had bolts on super tight and still had a leak what sealant would you use?

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Re: Coolant Pipe Bolt Hole Stripped! 850

Post by JimBee » Wed Jul 18, 2018 9:33 pm

I'm wondering if the flange somehow got out of plane so it's not totally flat. Not sure how that could happen but that seems to be how it's behaving.

Re: the anaerobic sealant. The main producer is Permatex. They have a technical assistance line. I once spoke with the tech on picky questions. My memory is kind of fuzzy but seems like it's rated for oil, transmission fluid and gas. There might be 2 or 3 differently rated versions. You used it on top of the cylinder head. (It's a while since I've had the camshaft cap off so I don't recall if coolant comes in contact with it there.)
I'm thinking that absent oxygen, it will swell to fill a gap the thickness of a fingernail. What we don't know is how much pressure it will hold. Or if it's best to apply it to cool surfaces. I'd probably call Permatex with those questions.
The problem you'll have is getting a liberal coating between those surfaces. If I were in your situation, I might well try it, knowing that if it doesn't work the head will be coming off again. If so, ask a rebuilder if you can reuse the head gasket. For sure you can reuse the o-ring spark plug seals, camshaft seals, etc.
Good luck!

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Re: Coolant Pipe Bolt Hole Stripped! 850

Post by SuperHerman » Wed Jul 18, 2018 11:02 pm

I don't think anaerobic sealant will work. It dries through the absence of air - so heat will not matter. It may not even cure.

How hard is it to pull that coolant pipe and check to see if it is true and if your block is clean of old sealant?

If you are going the Hail Mary route I would use some Right Stuff, put it on extra thick (but even) on both sides of the gasket so that it absorbs any imperfections. Then tighten to torque. As you may have to pull the pipe anyway - I suppose it wouldn't hurt. Just be diligent so that you don't get any into the cooling system.

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Re: Coolant Pipe Bolt Hole Stripped! 850

Post by Dmck » Thu Jul 19, 2018 12:04 am

What sealant would you reach for in this SuperHerman?

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Re: Coolant Pipe Bolt Hole Stripped! 850

Post by SuperHerman » Thu Jul 19, 2018 6:43 am


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Re: Coolant Pipe Bolt Hole Stripped! 850

Post by mrbrian200 » Thu Jul 19, 2018 7:36 am

JimBee wrote:
Wed Jul 18, 2018 9:33 pm
I'm wondering if the flange somehow got out of plane so it's not totally flat. Not sure how that could happen but that seems to be how it's behaving.
That's what I was thinking, the flange needs to be milled flat. Theory: The car is old enough, the original gasket compressed over time or that gasket started soaking up coolant and expanded, warping the flange, at the points where compression force is weakest - right in the middle.

I was reading through all this last night. I like to solve problems. A couple hours later I had an idea as to how to get these surfaces to mate with each other without taking the head or pipe off the car. Take a piece of 600 grit reinforced sandpaper, place it between the head and the flange with the sanding side facing the pipe flange. Apply moderate pressure to the flange holding it against the head while drawing the sandpaper back and fourth between them. Use feeler gauges to keep track of your progress. Then finish with 800 or 1000 grit to smooth it out.

When you're happy with it, you'll have grit inside that pipe that will need to be cleared. So you're going to need to disconnect the hose at the radiator, cover over the hole on the head with something, like thin plastic, and blast the grit and junk out of that pipe with water or compressed air or something.

This might be time consuming, but short of removing or replacing the pipe (and/or the head) I can't think how else you might get these surfaces to mate properly. These gaskets get much of their strength through compression force. A weak spot in the middle where the flange is warped would have a higher risk of blowing out under pressure even if it were sealed up with an adhesive sealant.

Some gasket materials are more 'squishy' than others. You might investigate aftermarket gaskets that might be designed to accommodate imperfections like this.

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