Bad coolant leak for a few minutes during cold mornings

[Cubey]

Two days ago, I cranked up the van and got going. I heard squealing like a belt or empty power steering pump. I pulled over and found everything soaked in coolant. It wasn't very warned up yet but was from a few miles on the highway.

I shut it off and looked around good. Back driver side of the radiator looked wet.

I have a safety radiator cap with the red lever and I let off the pressure. It was entirely full. I got going again and the squeal went away. I pulled over at two more gas stations at the next to little towns only about 8-10 miles apart. It was dried up fully by the 3rd stop so i kept going. No more leaks for the 72 mile total drive.

Yesterday wasn't as cold and i left a little later. Saw no leaks at all.

This morning was colder and i didn't check because i kinda forgot again i heard squealing. Stopped and it was soaked. Popped the cap again it's full. Cranked it up again and saw no obvious leaks. Again about 70 miles and no leaks. Back side was wet..I can't see the back side in unless the engine is off because i have to shove a long tube type light against the fan to see.

It's as if it's shooting a stream from the radiator but only on cold mornings. Engine temperature is fine, 190ish going 60-65mph.

The radiator does have pressure that pushes into the bottle when i pop the cap.

 

[chickenpot]

Ive had this happen around 0F it puddles coolant while warming up., maybe a palm size after 15 mins. It could be the water pump shaft seals or one of the hose fittings on the top of the pump. It didnt leak after it was warm so i never saw where it was coming from

 

[ihc1470]

Get a pressure tester on it when it is cold that should show you where the issue is. Might just tighten all the hose clamps. Sometimes they will be loose enough to leak cold and as things warm up they will seal again. Pressure tester is the best bet though.

 

[Cubey]

Get a pressure tester on it when it is cold that should show you where the issue is. Might just tighten all the hose clamps. Sometimes they will be loose enough to leak cold and as things warm up they will seal again. Pressure tester is the best bet though.

Could be the lower hose. I'll look into that.

Ive had this happen around 0F it puddles coolant while warming up., maybe a palm size after 15 mins. It could be the water pump shaft seals or one of the hose fittings on the top of the pump. It didnt leak after it was warm so i never saw where it was coming from

I hope it's not the water pump. I replaced it in January. It seems like its coming from further forward but who knows. Either the lower hose or the radiator.

 

[chickenpot]

Id start with your hose clamps and see

 

[Clb]

In a fwiw sorta way...
I replaced the heater hoses with napa's best product some time back.
The core connection started to leak, tightened, nope, trimmed and replaced the clamp, nope.
Replaced the hose with more of the same, nope.
Got pissed and took the first new hose and plugged 1 end and put h20 pressure into it, set it aside to observe....
M.F ing hose was porus.
Reconfirm with remaining sections, yepr **** leaked.
Ymmv
Also found that a new hose will now require retorquing once it sets for a while.
Never had these issues b4.

 

[Cubey]

Id start with your hose clamps and see

Yeah I'm thinking it's the lower hose at the radiator. The RV's always dripped a little, even though it was replaced and the clamp was tight.

I replaced this hose too and it has been more leaky than the RV's. I found it starting to drip this evening despite the radiator still being pretty warm. I saw a big area on the cement but it turned out to just be dry old spot from someone else who parked in the same spot.

I have a t-bolt clamp on it with a lock nut at the radiator end, so you'd think it wouldn't have worked loose. I don't know if I can even tighten it anymore without risking damaging the radiator. I put the t-bolt clamp because it kept leaking a fair bit from worm gear clamps working loose constantly.

I might have to just leave it alone until next spring and just put up with that problem until then. I need to drain the radiator and pull off the hose, so I can examine the hose barb on the radiator.

Unless I get a bunch of clean 1 gallon jugs and drain it like I did last winter when I replaced the water pump down in the desert.

I dunno if I should replace the hose again after it gets disturbed or not.

 

[ihc1470]

If room for a second clamp you might try that.

 

[franklin2]

All you usually have to do is go around and snug the hose clamps. Do them all with a 5/16 nut driver. I bet it will stop. It's just from the rubber in the hose shrinking under the clamp.

I used to hate those aggravating hose clamps the factory used that were made out of wire and you had to squeeze to release. I just thought they were cheap junk the factory used. Found out from a mechanic those clamps are actually the ones to use. They are called constant tension clamps, and keep pressure on the hose connection, even when the rubber shrinks underneath. Those type clamps will not have this problem.

I just had to tighten the clamps yesterday on my BII, it was doing the same thing. It has worm clamps all over it. I just went around and snugged them all with a nut driver, they were all a little loose. Once you get some age on the hoses, they will stop shrinking.

 

[Cubey]

Well i tightened the lower clamp a bit. And it sprayed again.during a slow 1mi drive to a park

It might have been the upper hose at the radiator, since that side seemed to be more soaked when I looked. I got out the hand driver again and it did tighten up a bit (worm gear clamp).

So maybe that's all it was. It's just hard to see where it's coming from because it only does it during driving and the fan blows it everywhere. I saw nothing leaking when I looked immediately after cranking it up first thing this morning.

I probably won't know until tomorrow now.

 

[IDIBRONCO]

They are called constant tension clamps, and keep pressure on the hose connection, even when the rubber shrinks underneath. Those type clamps will not have this problem.

This is not true at all. It is the theory though. Back in the 90's, I put new radiator hoses on for a customer while replacing his engine and reused his constant tension clamps. He and his wife stayed at a local motel overnight. The next morning, it was cold and there was a big puddle of coolant underneath their truck. Two out of the four clamps were leaking so I replaced them with worm style clamps and have never used constant tension clamps again. Maybe it was a fluke, but that's how I do it.

 

[franklin2]

I do not know how shops do it. If I ran a shop and replaced any hoses in the cooling system, and used a worm clamp, I would have to reschedule a visit 2 or 3 weeks later. Tell the customer to stop by and I would have to tighten the worm clamp.

It's like clockwork, If I replace a hose with a new one, a few weeks later it's going to do this leaking thing. Usually not when hot, but in the warm-up stage or the cool down stage. Now if I re-use a old hose, and carefully put the old clamp back on like it came off, sometimes I can get by without any leaks.

They make worm clamps with springs behind the screws. I wonder how they work, I have never tried one.

 

[Cubey]

They make worm clamps with springs behind the screws. I wonder how they work, I have never tried one.

I've seen photos of t-bolt ones with springs but not worn gear ones.

 

[franklin2]

Here's one. Don't know if they are available in all sizes or not.

Constant Tension Hose Clamp 2.59in-2.94in High Torque | 1405208

Spring loaded 300 Series Stainless Steel band clamping force remains consistent through heat cycles. Sold individually.

us.bddiesel.com

 

[MtnHaul]

I have had two ring clamps that looked OK but had actually split and the connection was leaking despite visually checking out. Once I lost my lower rad hose and the other time I thought my thermostat housing was leaking but the clamp was allowing coolant to leak out at a steady rate.
Constant tension clamps would be nice on the rad hoses. The guy at the local hose shop explained constant tension clamps as being particularly suited to high heat applications because the spring is rated to expand before the metal comprising the circular clamp portion so the extra tension is applied before the clamp can loosen due to heat expansion. Phew. I plan to swap some basic clamps to constant tension, but you do have to get the size just right as the constant tension offer almost no range of adjustment.