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tru-jack

Heater went cold

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tru-jack

Heater was working fine until today and now it only blows cold air... any ideas?

It was dark when I got home but I did take the hose off the block and blew the water out through the other hose that I disconnected from the y pipe and it didn't seem clogged. the fans blow, just cold air and I know you must be moving to make heat as it worked fine yesterday.

thanks

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stonelx

Try blowing air through both hoses again. Dump water down each and see if it comes out both.

Also, next time your out, feel both hoses. Both should be hot. ( I think :blush: )

If one is hot and the other cold, then something is blocking the water flow at the core.

Edited by stonelx

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tru-jack

thanks, the hoses at the heater weren't as warm as the one on the engine block, and the return at the y pipe wasn't as hot as the supply from the block, so I was thinking there was a possible blockage as well. Please correct if I'm wrong, but other than the supply and return water, the vent hoses and the power supply there isn't anything else to the heater core, so it must be a blockage? I sure hope it isn't anything else as it's basically a new boat.

thanks again for any help.

Edited by tru-jack

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stonelx
and the return at the y pipe wasn't as hot as the supply from the block, so I was thinking there was a possible blockage as well.

I woud guess so. Just had this same problem with my truck's heater. Back flushing it out fixed it.

I had blockage, or air pocket. (my rad fluid was low too) Maybe thats the same with your core.

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eyepeeler
and the return at the y pipe wasn't as hot as the supply from the block, so I was thinking there was a possible blockage as well.

I woud guess so. Just had this same problem with my truck's heater. Back flushing it out fixed it.

I had blockage, or air pocket. (my rad fluid was low too) Maybe thats the same with your core.

Thermostat? Is the temp gauge on 160?

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tru-jack

yes, the temp guage is at 160, and I can pour water into either the supply and return hoses and blow them out. They do feel a little retsricted. Any suggestions or cautions to flushing with a hose? don't really want to take the unit out if I don't have to. I did notice when I blew it out from the return end it was a little rusty or maybe just dirty? I would think there is a thing as too much flush out pressure, would a garden hose be too much? thanks all.

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VinRLX

I would think the garden hose would be ok, but maybe don't run it at full pressure. Also possible that you had a blockage at the Y fitting, perhaps weeds or something drawn in from the impeller through the raw water fitting. You may have already fixed the problem and not know it until you run the boat again.

Were you in weedy or mucky water when this happened???

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Lovetoski

I have the same problem! Interesting. Was told it only works when the boat is moving. But it isn't very warm at all??? Let me know if you come up with anything

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tru-jack

Jack, yes I was in some weedy and mucky water, and hopefully it did fix up as I ran the hose through it at lunch, but didn't dunk it in the lake because I unfortunately have to work, this job thing is really cutting into my skiing time... I used the hose to flush the heater from both connections at the motor and also in the Y fitting so I'm hoping something was stuck and is now gone, I will know tonight if I can get out for a rip. I hope I don't have to pull the core out, as I can't do yoga and can barely fit under the dash...

L2S, I will post if this fixed the problem, because on saturday is was nice a warm, then sunday, no warmth so I'm hoping it was as simple as just being clogged up a bit. I'll let you know.

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tru-jack

still no heat so I pulled the Y fitting and it wasn't full of debris as I hoped, but man is the hole small.. I would guess the hole within the y or smaller portion of the fitting is about the size of a #10 screw at best.. So I can easily blow water through the heater from the supply hose from the block and it comes out of the hose that connects to the Y but if I leave the Y on, I can barely blow water through, almost as if the hole is too small? The funny thing is this thing worked great 2 days ago and I'm pretty sure the hole in the Y didn't shrink. One more thing, when I pulled the return hose off the Y there wasn't any hot water coming out, so definately the hot water is not going through the core and back through the Y, the question is why not, where is it not getting through because when it's not on the Y it's easy to blow through. Need help on this one, thanks everyone.

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SunriseH2OSkier

Not sure what else to tell you to check. FWIW I can confirm that the hole in the Y fitting is indeed a small one - and it works just fine that way on my boat. I think that is how they regulate the flow of water through the core. Just doesn't need to flow any faster to provide sufficient warming through the exchanger.

As for your comment on pulling the hose from the Y and not getting any hot water out - I'm not surprised by this. You need the return hose hooked up in order to get the benefit of the raw water pump pulling the water through the core. Water will not flow naturally out of the intake manifold port that supplies the hot water to the heater.

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tru-jack

perhaps raw water pump line is clogged enough not to pull the water? isn't there a screen somewhere I should check? thanks

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tru-jack

Took it apart before work this morning and pulled a bunch of weeds out of the screen just south of the transmission cooler. This was good to get out as this would have been greatly restricting cool water flow to the tranny, and hopefully it was this reduced flow that wasn't providing enough flow / suction to the Y adapter to flow through the return hose of the heater. but now at work, and we're supposed to get thunder storms and rain for the rest of the day. Please all comments or suggestions are welcome as I think I'm covering almost everything, but advice is always appreciated. thanks

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SunriseH2OSkier

Is your Y adapter installed between the thru-hull and the raw water pump, or between the raw water pump and your tranny oil cooler? If the latter, it is definitely not as effective as it could be, even if things are clean as a whistle. Maybe the weeds you pulled are enough to make it that much less effective?

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tru-jack

It is between the raw water pump and tranny cooler as per factory install. If I move it I will have to cut into steel re-inforced line? (any tips to do this) Is it really that much more effective? I do know that it worked well last week.

thanks, and hopefully the removed weeds will help out the current problem.

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wienrdog
I will have to cut into steel re-inforced line? (any tips to do this)

1) Use a cutoff wheel.

2) Use a knife to cut though hose around the wire, then clip wire with nippers.

3) Use a hacksaw to cut & make sure when you run into the wire to rotate the hose so the blade cuts the wire from outside to inside, not along the wire.

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VinRLX

As above on cutting the reinforced raw water line.

Yes, it DOES work noticeably better at low RPM if the Y is placed BEFORE the impeller.

I think the weeds you pulled out of the tranny cooler screen will take care of your problem. Reinstall the Y before the impeller and you will love it. This was one of the first things I did to my 08. Factory has the proverbial thumb up the proverbial A$$ when it comes to this.

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tru-jack

thanks Jack, so the new location of the Y sounds simple, what did you do to fill in the void from where you removed it? Would this be a good place for a Sherwood raw water strainer? thanks

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VinRLX

No, a strainer would be first after the raw water fitting.

I think I used a 1" pvc fitting for the gap.

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Lovetoski

I took my boat in to the dealer (warranty) for heater not working. They said something was hooked up backwards. Tested it out today. Still blowing cold air? Brand new boat. Any ideas???

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VinRLX
I took my boat in to the dealer (warranty) for heater not working. They said something was hooked up backwards. Tested it out today. Still blowing cold air? Brand new boat. Any ideas???

yup. Take it back again. And/or search this site and see what you can learn about heaters.

Aside from that, give more info (boat model, year, motor) and give us more detail/questions.

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Lovetoski
I took my boat in to the dealer (warranty) for heater not working. They said something was hooked up backwards. Tested it out today. Still blowing cold air? Brand new boat. Any ideas???

yup. Take it back again. And/or search this site and see what you can learn about heaters.

Aside from that, give more info (boat model, year, motor) and give us more detail/questions.

It is a VLS 20 ft v drive. I tried it again yesterday afternoon, after the boat was running for a really long time. Warm air finally did start blowing out. Does this make sense????

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VinRLX
I tried it again yesterday afternoon, after the boat was running for a really long time. Warm air finally did start blowing out. Does this make sense????

Yes. The motor needs to be up to operating temperature (160°) before the air will really get warm. Also, in order for the water to circulate through the heater, you need to get the boat up and running. Unless, of course, you have the Y fitting installed before the impeller.

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Lovetoski
I tried it again yesterday afternoon, after the boat was running for a really long time. Warm air finally did start blowing out. Does this make sense????

Yes. The motor needs to be up to operating temperature (160°) before the air will really get warm. Also, in order for the water to circulate through the heater, you need to get the boat up and running. Unless, of course, you have the Y fitting installed before the impeller.

The boat is up and running and at temp of 160---it took about an hour b4 anything half way warm started coming out...this doesnt seem to make sense.

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VinRLX
I tried it again yesterday afternoon, after the boat was running for a really long time. Warm air finally did start blowing out. Does this make sense????

Yes. The motor needs to be up to operating temperature (160°) before the air will really get warm. Also, in order for the water to circulate through the heater, you need to get the boat up and running. Unless, of course, you have the Y fitting installed before the impeller.

The boat is up and running and at temp of 160---it took about an hour b4 anything half way warm started coming out...this doesnt seem to make sense.

Then you had a blockage or some other problem with circulation.

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