throwing elbows

[idrivejunk]

Throwing elbows is a mosh pit reference, ha ha.

Man, I know I been around here long enough to know all about heater hose elbows but I have to replace them every few months now and I don't understand.

Mainly I don't understand how the design was expected to work in the first place. They move. It can't.

So, before I set about re-engineering something... talk to me. I could rattle off all that I have tried, and I think I have read it all but I have some questions.

Anybody tap the engine side for NPT threads?

Anybody block the holes with a freeze plug?

Anybody add a second O ring?

Anybody try something else I haven't thought of?

I am tempted to pack a rope seal of some kind in behind the O-rings.

I would like to try hose clamping the elbows to a bracket attached to the nearest available bolts. Just to avoid movement during thermal cycling. But the design leaves me wondering if the elbows are intended to move a little to avoid something else.

This is just a way way way too often repair. Two oil changes means elbow change. Is there hope or is this just my life now?

Thanks for any fresh input.

[Scottydoggs]

you could by pass the alt bracket by tapping the holes like you said. the aussies have a factory bypass they use iirc.

have you cleaned them holes out real good? 100 grit sand paper can help, mine had some kinda varnish looking crap in them that i had to chip out with a pick, then i sanded smooth. never leaked. also lubed them o rings up before i pushed em in. you also need to make sure the top elbow is square to the bracket and lim as you tighten the alt bracket bolts down.

[PurpleGuy]

I'm sure tapping or using freeze plugs would work. I haven't really had an issue on mine. My old purple car I put metal elbows in and even though lots of people say not too I load those things up with grey rtv. I did the same when I put the engine in my Buick. It's only been about 9K but hasn't leaked a drop. Same deal. Just loaded them up with rtv.

[bandook]

I'm with Scotty, ....again dang it. I think you have corrosion in there. Clean it until it's smooth as a snakes ass. Also, double check the o-rings on the elbows. I remember seeing people state that the o-rings were cut on their new ones. I think the o-rings are the weak link, as they can come with cheap ones. Then just a smear of Vaseline before you install them.

Only other thing I can think is you have a deep scratch where the o-rings seal. Might need a new alt bracket and/or LIM.

[ItHurtz]

My experience timing cover is to thin to tap directly, it was thickened with tig and tapped again.


20170605_174114 by Corey S, on Flickr

20170618_144702 by Corey S, on Flickr

[idrivejunk]

you could by pass the alt bracket by tapping the holes like you said. the aussies have a factory bypass they use iirc.

have you cleaned them holes out real good? 100 grit sand paper can help, mine had some kinda varnish looking crap in them that i had to chip out with a pick, then i sanded smooth. never leaked. also lubed them o rings up before i pushed em in. you also need to make sure the top elbow is square to the bracket and lim as you tighten the alt bracket bolts down.

Aussie bypass? More info please.

I clean them holes out real good every time. Gently. Inspecting with a mirror, cleaning with wire brush on Dremel and patiently scraping away deposits with a wooden tool. I would think that 100 grit on aluminum would knock off enough metal to cause a leak mighty quick

At least the top elbow can be grabbed and wiggled and moved, so it is not binding. Every set of elbows has always sealed when new.

[idrivejunk]

I'm with Scotty, ....again dang it. I think you have corrosion in there. Clean it until it's smooth as a snakes ass. Also, double check the o-rings on the elbows. I remember seeing people state that the o-rings were cut on their new ones. I think the o-rings are the weak link, as they can come with cheap ones. Then just a smear of Vaseline before you install them.

Only other thing I can think is you have a deep scratch where the o-rings seal. Might need a new alt bracket and/or LIM.

Haven't found corrosion, been in there with dentist's mirror and maglite every time, every hole. It is not just one trouble spot, it is random which spot leaks.


I have found a twist in an O-ring once. I rank metal elbows according to how long they last for me... Dorman worst, GM better, Napa best. I did a burnout at Napa yesterday, they were closed at 6:15 yesterday and don't open Sundays.

I would probably rather install my spare 135K engine than swap the timing cover. I don't recall that spot ever leaking though. Buying new parts is pretty much out of the question but I realize that would be GM's solution.

[idrivejunk]

I'm sure tapping or using freeze plugs would work. I haven't really had an issue on mine. My old purple car I put metal elbows in and even though lots of people say not too I load those things up with grey rtv. I did the same when I put the engine in my Buick. It's only been about 9K but hasn't leaked a drop. Same deal. Just loaded them up with rtv.

I have tried RTV when I was still daily driving the GT. Can't say it made much difference in time until leakage but it adds a great deal of fuss and potential for damage when cleaning and replacing.

I am just about fed up enough to use RTV and plastic elbows, although the metal ones are never in there long enough to corrode and break off. What type RTV have you used that seems to be working?

[idrivejunk]

My experience timing cover is to thin to tap directly, it was thickened with tig and tapped again.


20170605_174114 by Corey S, on Flickr

20170618_144702 by Corey S, on Flickr

Money shot! Thank you for this bit of info and pics. That is exactly what I suspected. I don't own a TIG nor have much faith in welded castings but again, thanks.

[idrivejunk]

So, not one of you thinks that holding the elbow still with a bracket could help?

Iron Pontiac V8 heads use a stamped barbed nipple which is driven in like the dust cap on a tapered roller wheel bearing and they don't leak or require sealant. If the existing bosses could be drilled to remove taper from the O-ring bore about a half inch deep, I could make barbs. If theres enough metal to withstand threading an NPT barb in enough to seal, it can withstand tapping a sheetmetal nipple in. IMO. But I don't have the access or the drill bit.

I will just have to venture into the garage and experiment. Seems the only way to win is to buy stock in coolant and elbow manufacturers.



Next questions:

How to get a thermostat that works as well as those made last century? Without ordering a robertshaw one online.

How to get a good radiator cap? Last one I bought for it didn't even fit onto the radiator.


Much obliged to you gents for your input so far. Think good thoughts.

[PurpleGuy]

I have tried RTV when I was still daily driving the GT. Can't say it made much difference in time until leakage but it adds a great deal of fuss and potential for damage when cleaning and replacing.

I am just about fed up enough to use RTV and plastic elbows, although the metal ones are never in there long enough to corrode and break off. What type RTV have you used that seems to be working?

I just use ultra grey. Ultra black would be fine as it's more oil resistant but the grey looks nicer when it's done. I smear it on the o rings, shove them in. Then once they're in I try to push some in.

Next questions:

How to get a thermostat that works as well as those made last century? Without ordering a robertshaw one online.

How to get a good radiator cap? Last one I bought for it didn't even fit onto the radiator.


Much obliged to you gents for your input so far. Think good thoughts.

I've always used Stant or Gates. Never had an issue yet. I put a 180* stant in my old purple car and that was in there for about 80K miles and never had an issue. It did overheat cause the rad was crap but that wasn't related to the thermostat.

[idrivejunk]

Alright then, thanks guys. I made a bracket to hold the leaking elbow still. Hose clamp, strap to intake bolt. I'll see if that makes a difference.It was leaking air on cooldown the other day but stopped when I pushed on the elbow. So maybe.

[GTPpower]

I always run a bead of red rtv around the orings. I've never had one leak in the 15 years I've been doing that.

[idrivejunk]

I always run a bead of red rtv around the orings. I've never had one leak in the 15 years I've been doing that.

So you have done one elbow replacement in that time?

What is red RTV?

I guess thats the trouble. I used RTV a time or two but stopped because of what I read here. Been replacing twice a year ever since. Just plain bad info causing me lots of hassle. The trust is gone, RTV is in.

Driving the GT until I get another paycheck or two and can solve the problem. Without further input. Thanks.

[GTPpower]

I've done it on many cars. Never has one leaked.

This is what I use.

Permatex(R) High-Temp Red RTV Silicone Gasket Maker - Permatex

[QUICKSILVER462]

For reliable coolant elbows on the S2 and S3 3800, I found best NOT to use the o-rings that come supplied in the replacement coolant elbows kits, but rather use an o-ring slightly over size (ring diameter, not overall diameter), the holes in the manifold and alt. bracket must be perfectly clean, small pits in the aluminum are not a problem, lube the o-ring with oil, then insert.
I have found the o-rings supplied in the "HELP" coolant elbow kits get hard with age and heat, then loose their elasticity and then leak when the engine cools down.

[idrivejunk]

Pretty much everyone who responded was right one way or another. That is the upper bore on the bracket.

I added old O-rings as RTV dams-



Smeared Ultra Blue in that one bore then did this-





Dry after a couple days' use. FYI

[bandook]

Lol, reminds me of the days where I was trying to fix my evil SD header leaks. Hey, here's to hoping!

[BillBoost37]

Wondering...why I never had these issues.

One thing I always did was lube the o-rings, refuse to rtv them and as I was tightening the various brackets..I would wiggle the elbows. If they don't look square to the holes they are in.. you are going to have issues.

[idrivejunk]

Yeah I grew weary of changing elbows. Any of the ones I have had, you can wiggle the elbows after installation. I don't have to understand, just solve! And there you have it. This engine does have 278K, not it's first rodeo.