[BenMC]

imported post

My 1500 has a hising sound coming from the engine somwhere. When I blip the throttle lightly I can hear it and the idle doesn't seem as stable as it was last week. Any suggestions as to where I should start looking?

 

[wexy]

imported post

While I am not a guru ,it sounds like a vacum hose has come loose ,,check all the small hoses around the carbs,I also think there are some just inside the fuel tank filler ,,But I am sure one of the GURUS will come on line and tell you exactly what it is ..cheers Ciaran ,:waving:,,

 

[Jack Joyce]

imported post

One of the most common vacuum leaks occurs at the vacuum take-off on the intake manifold. There's a hose there that makes a sharp bend right off the connection to the manifold and it often cracks at the stressed point. You'd find the one that leaked on me on the right side immediately above where the intake manifold mates to the head. I think there's another one on the opposite side of the engine.

These are the same points at which you'd connect to synch the carbs.

You'll have to peel off the same plastic necessary to change the plugs to get to it on each side.

Jack

 

[GWEddie]

imported post

Sonds like a vacuum leak all right, specially if the idle is going a bit odd.

 

[Jason]

imported post

The vac hoses on the manifolds are usually the first to crack at the edges, like Jack says. Also the plastic T junction under the left fairing pocket can just break (Honda replaced these under warranty) and suck in air. Check all those easy ones before digging deeper.

 

[exavid]

imported post

Check the saddlebags for a cat stowaway! :jumper:

 

[Goldwinger]

imported post

Snakes are a possibility too.:shock::shock::shock:Now if you lived on the Emerald Ile, you wouldn't have to worry about snakes..:grinner::grinner::grinner:

 

[exavid]

imported post

Get a piece of tubing like vacuum line and use it like a stethoscope. (for REDWING that means stick one end in your ear)Should be able to localize the sound that way.

 

[BenMC]

imported post

It was a plastic T piece on the left side of the carbs that had failed and was sucking air. Got a new one and it's all fixed now. I had teh carbs balanced while the mechanic was at it. Thanks for your help everyone, spot on as usual.

 

[Eamonn1200]

imported post

BenMC wrote:

It was a plastic T piece on the left side of the carbs that had failed and was sucking air. Got a new one and it's all fixed now. I had teh carbs balanced while the mechanic was at it. Thanks for your help everyone, spot on as usual.

I think there was a Honda service bulletin about this T pieceyears ago. Can't be sure as I don't own a 1500, but it does ring a bell.

 

[BenMC]

imported post

I think you are right Eamonn. The mechanic mentioned this when he came back with the new part.

 

[Heffo]

imported post

I had this happen once, the hose on the right head cracked and itcaused terrible problems. The engine would cut out and idle very rough. I was relieved that it was only a cracked hose and nothing more expensive.