98 Suburban- heater hose HUGE LEAK-can I clamp or bypass it?

Discussion in 'General Chevy & GM Tech Questions' started by phoebeisis, Jul 27, 2011.

  1. phoebeisis

    phoebeisis Epic Member 5+ Years 1000 Posts

    I have been smelling coolant for a long time.1998 Suburban 2wd 5.7 1/2 ton 216,400 miles
    1.5 years ago I paid and ham handed power tool equipped "mechanic" to strip my harmonic balancer bolt, my oil pan drain bolt,several oil pan bolts.
    and who knows what else.
    Oh he was supposed to be changing out the intake manifold gaskets -and they were leaking-I don't think they are leaking much now, but I'm dreading ever going back over that to see what else he stripped(idiots should be allowed around electric wrenches!!)

    Well I checked my coolant-I had been using a little- maybe 8 ounces 3 months-
    Today it seemed to be smelling more-so I checked it- 1.5 GALLONS LOW!!
    Looked around-and I found coolant dripping very rapidly from this hose- it seems to be leaking right where the hose bulges out into this bigger hose-there appears to be some sort of metal clamp(not a hose clamp- more some sort of crimp thing)
    It seems to be just past a plastic manifold(where 2-3 hoses come together)

    My question-just what is this hose- heater hose I'm guessing?
    Can I just clamp off both hoses?
    Or can I just stick one hose into the other- bypassing the heater??
    It would be easier and cheaper to just clamp both hoses-I don't need a heater in South Louisiana
    I am broke, what do you think is the cheapest easiest way to just bypass everything for now.
    I haven't gotten under the truck yet to get a really good look.
    Here is a picture of where it is dripping-where the hose sorta bulges out- it is the hose dead in the middle- second from the bottom-the one that enlarges for some damn reason
    What is the simplest cheapest way to get it running quickly-forget the heater for now
    PS it didn't overheat-guess most of the leaking happened after I parked it. P1010057.jpg P1010057.jpg
    Last edited: Jul 27, 2011
  2. Crawdaddy

    Crawdaddy All hail the Mad King!! Staff Member 5+ Years 1000 Posts Platinum Contributor

    Can we get a picture with a wider view of the issue? If it is indeed a heater hose, one heater hose should be going to the intake manifold, either all the way at the back of the intake or all the way at the front of it. The other heater hose should be going to the radiator, usually pretty high up on the side tank. If it is a heater hose that's leaking, you can bypass it by getting a heater hose repair kit from the parts store and hooking up the line coming from the intake directly to the hose going to the radiator. That'll bypass the heater.
  3. phoebeisis

    phoebeisis Epic Member 5+ Years 1000 Posts

    Thanks for the response
    When it quits raining I'll get a picture.
    It looks like one hose comes out of the intake,and one comes directly out of the water pump.
    They both head rearwardward- BUT THEN 2 hoses turn into 4 or 5 hoses!!

    The 2 hoses go into a couple of manifolds and split up-2 going into firewall and two going rearward(one intake one return I guess)
    It looks like the hose from the intake manifold springs a leak just after it goes into the splitting manifold-
    It is a real mess of hoses in there!!
    So there is some sort of cheap out heater hose repair kit- that is good to know.
    Autozone will have some sort of generic repair kit that I can adapt to just bypass the whole mess?
  4. stephan

    stephan Rockstar 4 Years 5000 Posts

    A good reason to work on your own rig Charlie. Just wait till you're not looking & the same "ham handed" mechs twin brother at the tire shop rams your lug nuts on with an impact wrench & warps your drums, as many have posted on here.
  5. Crawdaddy

    Crawdaddy All hail the Mad King!! Staff Member 5+ Years 1000 Posts Platinum Contributor

    Do you have rear heat? If so, the manifold is to split the hot water between the front and rear heaters.
  6. phoebeisis

    phoebeisis Epic Member 5+ Years 1000 Posts


    Yes I have 2 good reason to work on my own stuff
    1) Broke
    2) Don't have to worry about some FU making things worse- heck I can make things worse for free-I don't need to pay anyone to do it!!
    I was actually happy to see the heater hose leaking- sure beats manifold gaskets, or radiator, or heater core.
    Can't say I was happy to see it was 1.5 GALLONS LOW!!But most must have leaked after I got home.Probably been seeping for a while, but it must have really split/blew! Hope I didn't miss the gauge pegging itself!
  7. 2COR517

    2COR517 Epic Member 5+ Years 1000 Posts

    You can't block the heater hose, but you can bypass the heater cores. You just need to make sure the hose coming from the top/front of the intake manifold returns to either the water pump or radiator.
  8. phoebeisis

    phoebeisis Epic Member 5+ Years 1000 Posts

    Right I wasn't thinking.
    If I clamped a pressurized hose-BOOM- coolant would blow all over the place.
    I kinda thought that maybe the heater was supplied as some sort of a partial bypass circuit where it was getting some low pressure flow, but if blocked would just bypass like a plugged oil filter.
    So the heater core ALWAYS is getting fresh hot coolant- but only pumps heat into the cabin when fans are on and some duct is open?

    Two questions;
    1) is the line to the top of the water pump a return line?So the line from the intake is the line sending coolant to the cores?
    2) In my picture-there is a line-probably the leaky one-that suddenly is sleeved in a floppy rubber sleeve. WHY is it sleeved like that-what is that kinda fragile looking rubber sleeve for?? It is clapped on with a narrow metal clamp-which might be where the leak is- it- the metal clamp might have cut the hose?Sleeve doesn't look like it would protect the line from abrasion much , but maybe it does???
    PS- I'm going to spend $20 on a whole bunch of hose connectors-ebay- various sizes and some are different ODs on either end.Pretty sure the lines are different diameters,so I need the connectors with two different ends- think they are 5/8 x7/8 OD or some such.
  9. 2COR517

    2COR517 Epic Member 5+ Years 1000 Posts

    You can't block the heater hose because its part of the cooling circuit for the engine. Coolant flows from the intake fitting, through the heater core, and back to the water pump. From the water pump, through the block, up through the heads, into the intake manifold, back out the heater hose. As the engine warms, the thermostat opens and directs some of the coolant to the radiator through the upper hose. The coolant transfers heat to the air as it flows through the radiator, the cooled coolant returns back to the water pump in the lower hose. The cooled coolant mixes with the coolant coming back from the heater core and circulates through the engine to keep it cool.

    So yes, hot coolant is always flowing through the heater core. The exception would be when you go to Max AC. There should be a vacuum operated bypass valve in the heater core lines. When you switch max AC, the valve "closes" and directs hot coolant directly back to the water pump.

    There are two size heater hose lines. 5/8 id connects the intake fitting to the heater core. 3/4 id connects the heater core to the water pump. So the only adapter you need is a 5/8 x 3/4.

    If you have a heater hose connected to the radiator, that's fine. It still goes back to the water pump through the lower hose. Some vehicles are setup this way to warm the transmission up faster, and it's possible that if you have both front and rear heat one goes to the water pump the other to the radiator.
    Last edited: Jul 28, 2011
  10. phoebeisis

    phoebeisis Epic Member 5+ Years 1000 Posts

    So the heater circuit gets the full flow of the coolant circuit except after the thermostat opens and sends a little to the radiator- ??
    Wow I never have had a heater line leak in 40 years of screwing with cars/trucks etc- never gave it any thought. I always pictured it as having no flow until you hot the heater switch and some sort of valve opened.
    The kit I ordered-$15 delivered has several 5/8 to 3/4 fittings-and a bunch of others.It would have been 1/2 that to just get the single fitting-and I might eventually use one of the other straight sizes to "repair" cut out my leak- I think the leak is to the back circuit.
    When it quits raining I'll get a better look

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