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Option for sealing throttle coolant bypass on the block

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Old 02-09-14, 08:59 PM
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Option for sealing throttle coolant bypass on the block

I deleted the bypass on the throttle body and I don't know what to do about sealing the entries on the block I though about using caps but I don't think they will hold up to time and pressure, I've though about threading it and using a plug for now I just have a hose looping them together. What have you guys used?
Old 02-10-14, 07:54 AM
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I'd previously been using the TB coolant line for my (aftermarket) temperature gauge sensor. I deleted it along with AWS and emissions during a rebuild, but kept the line. Like you, I just looped it front to back with my sensor. No issues over the years.

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Old 02-10-14, 09:45 AM
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Keep the loop going to the front. It helps get the air out of the motor.

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Old 02-10-14, 01:51 PM
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Believe it's been tapped 12x1.75 (?), and a ball valve installed. We've had that line split in the past, when running the stock system, rust on the nipple and assuming a line off a import motor was good, probably contributed.
Old 02-10-14, 03:10 PM
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The only problem I see with tapping it while the motor isn't torn apart is you could get shards of cast iron in the cooling system when cutting the threads. If the plates were separated from the engine, say during a rebuild, then it would be easier to avoid any contaminates getting in the engine.
Old 02-10-14, 06:04 PM
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Easy solution is to pump some water or coolant through into and from a bucket.

Clean passages.
Old 02-10-14, 07:03 PM
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The problem is that the rubber hose coolant line from the block to the throttlebody is damned near inaccessible with the engine in the car.

The end of the hose that goes onto the throttlebody is no problems.

But the end that goes down onto the barb on the back of the block is not possible to reach with the engine in the car, and all the stock accessories bolted on. The firewall is in the way, and the barb on the block is buried down too deep to reach the clamp.

Unless I am missing something really obvious here?
Old 02-11-14, 02:06 AM
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Originally Posted by riwanika
The only problem I see with tapping it while the motor isn't torn apart is you could get shards of cast iron in the cooling system when cutting the threads. If the plates were separated from the engine, say during a rebuild, then it would be easier to avoid any contaminates getting in the engine.
Usually just heavy grease down the nipple while you drill it out and on the tap does the trick to get the bulk. If you wanted to be doubly sure, you magnetize the tap as well.

You probably won't be able to use a standard tap holder with the engine in the car, unless you do half turns or less forever. I normally use a long, collet style T bar type to clear all the crap.
Old 02-11-14, 05:50 AM
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Originally Posted by SA3R
The problem is that the rubber hose coolant line from the block to the throttlebody is damned near inaccessible with the engine in the car.

The end of the hose that goes onto the throttlebody is no problems.

But the end that goes down onto the barb on the back of the block is not possible to reach with the engine in the car, and all the stock accessories bolted on. The firewall is in the way, and the barb on the block is buried down too deep to reach the clamp.

Unless I am missing something really obvious here?
^This is absolutely true. And a valid risk to keeping the line. No getting around it, that rear iron nipple would a bitch. I mitigated it with new hose and double clamps. But it's a good place for the sensor. And with typical fatalistic rotary logic, I also figured that the original stock hose lasted ~15 yrs and I'd probably be back into the engine before another 15 yrs.
Old 02-11-14, 08:44 AM
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Originally Posted by SA3R
The problem is that the rubber hose coolant line from the block to the throttlebody is damned near inaccessible with the engine in the car.

The end of the hose that goes onto the throttlebody is no problems.

But the end that goes down onto the barb on the back of the block is not possible to reach with the engine in the car, and all the stock accessories bolted on. The firewall is in the way, and the barb on the block is buried down too deep to reach the clamp.

Unless I am missing something really obvious here?
It's actually not that bad. If you have a LONG straight set of needle nose pliers, you can get the hose clamp to move up, then use a pair of hose pliers to break it free.

I've done a number of these hoses on the car with the rat's nest and everything there. It's not super easy, but it's far from impossible.

Now, if you foolishly replaced the hose clamp with a worm drive clamp, forget it.

To answer the original question, loop the hose from the back of the block to the water pump housing. That's the easiest and actually most reliable way to do it. Welding it shut can be problematic (pinhole leaks), rubber caps ALWAYS fail, just loop it.

Dale

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Old 02-11-14, 10:09 PM
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Thanks for the input guys
Old 02-12-14, 10:51 PM
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Cut it. Crush the pipe together. TIG weld it. Worked for me!
Old 02-13-14, 09:33 AM
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anybody cut and threaded the pipe and put a threaded cap on it?
Old 02-13-14, 02:00 PM
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I welded mine while rebuilding the engine, Wouldn't be as easy with the engine in the car.
Old 02-14-14, 01:24 PM
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Originally Posted by neit_jnf
anybody cut and threaded the pipe and put a threaded cap on it?
Nipple is 10mm OD with sub 1mm wall thickness at a guess....if you could without destroying it, the poofteenth of material that remains after the threading operation (what thread?) would be less reliable than retaining the hose.
Old 02-14-14, 01:55 PM
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You could cut the bead off the pressed in nipple and put a compression fitting/plug on it.

I have drilled and tapped them before.

I have put a section of fuel injection hose on it and a hitch pin (like a bolt, but not threaded) in the hose with clamps.
Old 02-14-14, 06:24 PM
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+1 for looping the line.
Old 02-17-14, 01:14 AM
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Loop.
Old 02-17-14, 12:03 PM
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I just cut the hose off, inserted a sufficiently size bolt with some RTV, clamped the end over the bolt and tied it down with a zip tie.

No leaks in 3 years or so.

Whenever the engine comes out I will do it properly.
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