Mystery Noise

[gary_electric]

I've got 1,500 miles on my rebuilt sedan engine, and just started getting a ticking sound that sounds like an under-dash rattle. I traced it to the heater box, but I think it's just broadcasting the noise from the engine. It sounds like a cable spinning within a jacket, sort of like a spedo-cable, but it coincides with RPM and not speed. I can hear it in the engine compartment, though it's much louder in the cabin. I add ZDDP when I do my oil changes, and have changed it three or four times since installing the engine. Unfortunately, I'm more of a cosmetic restoration guy, and not so much a mechanic, so any help would be appreciated!

[TOM THIES]

Gary
a good tool to have is a  auto stethoscope so you can hear inside the motor.  also if you add a hollow tube you can chase down outside noises.  a dowel pin works well too for the inside the motor noise, just hold the dowel pin to the motor in different places and than put it to your ear.  Watch out for any moving parts,,,lol.  hope this helps
Tom

> ----- Original Message -----
> From:
> gary_electric
> To:
> 2cylinderhondas@yahoogroups.com
> Sent:
> Thursday, May 30, 2013 5:18
> AM
> Subject:
> [2cylinderhondas] Mystery
> Noise
> I've got 1,500 miles on my rebuilt sedan engine, and just started getting a > ticking sound that sounds like an under-dash rattle. I traced it to the heater > box, but I think it's just broadcasting the noise from the engine. It sounds > like a cable spinning within a jacket, sort of like a spedo-cable, but it > coincides with RPM and not speed. I can hear it in the engine compartment, > though it's much louder in the cabin. I add ZDDP when I do my oil changes, and > have changed it three or four times since installing the engine.
> Unfortunately, I'm more of a cosmetic restoration guy, and not so much a > mechanic, so any help would be appreciated!

[dm600z]

Without listening to your car,   the problem could be a bunch of things.  But there are a few things you can do to help isolate the problem;
1)  disconnect the fan belt from the crank pulley to see if the source of the noise is related to the fan blower or pulley system.  You can run the engine without the fan for several minutes without doing any damage.
2)  disconnect the  speedometer at the reverse gear cover to see if it is the source of your nose
3)  remove the bellows which go from the heat exchanger to the hot air blower.  I have seen the heat exchanger loosen and develop a rattle.
you can use a screw driver or dowel pin to push on the heat exchanger (you will see it inside the heat exchanger when you remove the bellows) and see if it changes the sound of the noise.
4)  remove the cover to the air cleaner box and remove the air filter.  you may be developing a rattle in this area if the filter is not secure.  Also check the flap at the front of the air cleaner horn to make sure it is secure in either the winter or summer position.
If none of these ideas helps out,  the problem may be inside the engine or transmission.
good luck,
Dale

> I've got 1,500 miles on my rebuilt sedan engine, and just started getting a > ticking sound that sounds like an under-dash rattle. I traced it to the heater > box, but I think it's just broadcasting the noise from the engine. It sounds > like a cable spinning within a jacket, sort of like a spedo-cable, but it > coincides with RPM and not speed. I can hear it in the engine compartment, > though it's much louder in the cabin. I add ZDDP when I do my oil changes, and > have changed it three or four times since installing the engine.
> Unfortunately, I'm more of a cosmetic restoration guy, and not so much a > mechanic, so any help would be appreciated!

[richmccolman]

Just as Dale said, we don't have the advantage of hearing the noise ourselves, but as another data point, I'll mention that I have a noise in mine that seems to come through from the heat exchanger -- it sounds like a sporadic metallic buzzing, and reminds me a bit of a dry speedo cable. It gets louder when I turn on the heater. The noise starts up a few minutes after the cars has been running and is warmed up, and kicks in starting around 4,000 rpm.
I was worried at one point that it was inside the engine, but with a stethoscope, it now seems to be coming from inside the heat exchanger.
I only mention this as a point of comparison, so take this with a grain of salt, You shouldn't close out any possibilities, especially if it turns out to be something more serious.
Richard

--- In
2cylinderhondas@yahoogroups.com
, goinhm@... wrote:
> Without listening to your car, the problem could be a bunch of things.
> But there are a few things you can do to help isolate the problem;
> 1) disconnect the fan belt from the crank pulley to see if the source of
> the noise is related to the fan blower or pulley system. You can run the
> engine without the fan for several minutes without doing any damage.
> 2) disconnect the speedometer at the reverse gear cover to see if it is
> the source of your nose
> 3) remove the bellows which go from the heat exchanger to the hot air
> blower. I have seen the heat exchanger loosen and develop a rattle. you can
> use a screw driver or dowel pin to push on the heat exchanger (you will see
> it inside the heat exchanger when you remove the bellows) and see if it
> changes the sound of the noise.
> 4) remove the cover to the air cleaner box and remove the air filter.
> you may be developing a rattle in this area if the filter is not secure.
> Also check the flap at the front of the air cleaner horn to make sure it is
> secure in either the winter or summer position.
> If none of these ideas helps out, the problem may be inside the engine or
> transmission.
> good luck,
> Dale
> I've got 1,500 miles on my rebuilt sedan engine, and just started getting a
> ticking sound that sounds like an under-dash rattle. I traced it to the
> heater box, but I think it's just broadcasting the noise from the engine. It
> sounds like a cable spinning within a jacket, sort of like a spedo-cable,
> but it coincides with RPM and not speed. I can hear it in the engine
> compartment, though it's much louder in the cabin. I add ZDDP when I do my oil
> changes, and have changed it three or four times since installing the engine.
> Unfortunately, I'm more of a cosmetic restoration guy, and not so much a
> mechanic, so any help would be appreciated!

[Bill]

There are a number of tools that help find the problem, but one tool close to my work bench is the book, "Troubleshooting Old Cars by Ron Bishop".   As it says in the introduction; "Troubleshooting is a process of elimination to establish the facts, find out whether or not a suspected trouble actually exists, and to then track down the source in a logical manner." Ron goes on to say "I recommend that you do not make any adjustments or repairs until a complete analysis of the trouble is complete and that you are positive the source of the trouble has been located.  Working slovenly, trying this and that, while hoping to stumble on the cause of trouble could result in changing the effect of the trouble and thereby entirely disguise the actual cause of the trouble."
Bill

[gary_electric]

Thanks, Dale. Those are all great suggestions, and sound like possible causes. I'll let you know what I find.

--- In
2cylinderhondas@yahoogroups.com
, goinhm@... wrote:
> Without listening to your car, the problem could be a bunch of things.
> But there are a few things you can do to help isolate the problem;
> 1) disconnect the fan belt from the crank pulley to see if the source of
> the noise is related to the fan blower or pulley system. You can run the
> engine without the fan for several minutes without doing any damage.
> 2) disconnect the speedometer at the reverse gear cover to see if it is
> the source of your nose
> 3) remove the bellows which go from the heat exchanger to the hot air
> blower. I have seen the heat exchanger loosen and develop a rattle. you can
> use a screw driver or dowel pin to push on the heat exchanger (you will see
> it inside the heat exchanger when you remove the bellows) and see if it
> changes the sound of the noise.
> 4) remove the cover to the air cleaner box and remove the air filter.
> you may be developing a rattle in this area if the filter is not secure.
> Also check the flap at the front of the air cleaner horn to make sure it is
> secure in either the winter or summer position.
> If none of these ideas helps out, the problem may be inside the engine or
> transmission.
> good luck,
> Dale
> I've got 1,500 miles on my rebuilt sedan engine, and just started getting a
> ticking sound that sounds like an under-dash rattle. I traced it to the
> heater box, but I think it's just broadcasting the noise from the engine. It
> sounds like a cable spinning within a jacket, sort of like a spedo-cable,
> but it coincides with RPM and not speed. I can hear it in the engine
> compartment, though it's much louder in the cabin. I add ZDDP when I do my oil
> changes, and have changed it three or four times since installing the engine.
> Unfortunately, I'm more of a cosmetic restoration guy, and not so much a
> mechanic, so any help would be appreciated!

[gary_electric]

Thanks Tom, I'll give that a try!

--- In
2cylinderhondas@yahoogroups.com
, "TOM THIES" wrote:
> Gary
> a good tool to have is a auto stethoscope so you can hear inside the motor. also if you add a hollow tube you can chase down outside noises. a dowel pin works well too for the inside the motor noise, just hold the dowel pin to the motor in different places and than put it to your ear. Watch out for any moving parts,,,lol. hope this helps
> Tom
> ----- Original Message -----
> From: gary_electric
> To:
2cylinderhondas@yahoogroups.com
Sent: Thursday, May 30, 2013 5:18 AM
> Subject: [2cylinderhondas] Mystery Noise
> I've got 1,500 miles on my rebuilt sedan engine, and just started getting a ticking sound that sounds like an under-dash rattle. I traced it to the heater box, but I think it's just broadcasting the noise from the engine. It sounds like a cable spinning within a jacket, sort of like a spedo-cable, but it coincides with RPM and not speed. I can hear it in the engine compartment, though it's much louder in the cabin. I add ZDDP when I do my oil changes, and have changed it three or four times since installing the engine. Unfortunately, I'm more of a cosmetic restoration guy, and not so much a mechanic, so any help would be appreciated!

[gary_electric]

Good point. Thanks, Richard. I can't wait to tear into it this weekend. Fingers crossed for the heat exchanger being the cause...

--- In
2cylinderhondas@yahoogroups.com
, "richmccolman" wrote:
> Just as Dale said, we don't have the advantage of hearing the noise ourselves, but as another data point, I'll mention that I have a noise in mine that seems to come through from the heat exchanger -- it sounds like a sporadic metallic buzzing, and reminds me a bit of a dry speedo cable. It gets louder when I turn on the heater. The noise starts up a few minutes after the cars has been running and is warmed up, and kicks in starting around 4,000 rpm.
> I was worried at one point that it was inside the engine, but with a stethoscope, it now seems to be coming from inside the heat exchanger.
> I only mention this as a point of comparison, so take this with a grain of salt, You shouldn't close out any possibilities, especially if it turns out to be something more serious.
> Richard
> --- In
2cylinderhondas@yahoogroups.com
, goinhm@ wrote:
> > Without listening to your car, the problem could be a bunch of things.
> > But there are a few things you can do to help isolate the problem;
> > 1) disconnect the fan belt from the crank pulley to see if the source of
> > the noise is related to the fan blower or pulley system. You can run the
> > engine without the fan for several minutes without doing any damage.
> > 2) disconnect the speedometer at the reverse gear cover to see if it is
> > the source of your nose
> > 3) remove the bellows which go from the heat exchanger to the hot air
> > blower. I have seen the heat exchanger loosen and develop a rattle. you can
> > use a screw driver or dowel pin to push on the heat exchanger (you will see
> > it inside the heat exchanger when you remove the bellows) and see if it
> > changes the sound of the noise.
> > 4) remove the cover to the air cleaner box and remove the air filter.
> > you may be developing a rattle in this area if the filter is not secure.
> > Also check the flap at the front of the air cleaner horn to make sure it is
> > secure in either the winter or summer position.
> > If none of these ideas helps out, the problem may be inside the engine or
> > transmission.
> > good luck,
> > Dale
> > I've got 1,500 miles on my rebuilt sedan engine, and just started getting a
> > ticking sound that sounds like an under-dash rattle. I traced it to the
> > heater box, but I think it's just broadcasting the noise from the engine. It
> > sounds like a cable spinning within a jacket, sort of like a spedo-cable,
> > but it coincides with RPM and not speed. I can hear it in the engine
> > compartment, though it's much louder in the cabin. I add ZDDP when I do my oil
> > changes, and have changed it three or four times since installing the engine.
> > Unfortunately, I'm more of a cosmetic restoration guy, and not so much a
> > mechanic, so any help would be appreciated!

[gary_electric]

Thanks Bill. I was thinking the same thing. The last thing I want to do is pull a perfectly good engine, only to find the noise is being caused by a fan pulley bearing.

--- In
2cylinderhondas@yahoogroups.com
, "Bill" wrote:
> There are a number of tools that help find the problem, but one tool close
> to my work bench is the book, "Troubleshooting Old Cars by Ron Bishop". As
> it says in the introduction; "Troubleshooting is a process of elimination to
> establish the facts, find out whether or not a suspected trouble actually
> exists, and to then track down the source in a logical manner." Ron goes on
> to say "I recommend that you do not make any adjustments or repairs until a
> complete analysis of the trouble is complete and that you are positive the
> source of the trouble has been located. Working slovenly, trying this and
> that, while hoping to stumble on the cause of trouble could result in
> changing the effect of the trouble and thereby entirely disguise the actual
> cause of the trouble."
> Bill