TheSamba.com :: View topic - 2 questions- Cold starting and a hissing noise

Wed Nov 18, 2009 6:32 am

Pretty cold this morning, 25 degrees. I have started the bus before at about 30 degrees with no problem. This morning it would not start. Stopped short of killing the battery.

It bothered me so I did some forum searching. Went out about 15 minutes later. Reseated a few wires, starter, CSV, etc. Started right up! So what should I be checking over? Is it a connection or did the 15 minute sitting period have anything to do with it?

After starting it up I could hear a very audible constant hissing noise. Is this normal or do I need to look for a vacuum leak?

Also a pretty loud ticking noise until the engine warmed up about 5 minutes later.

So that's 3 questions I guess.

Thanks.

Wed Nov 18, 2009 6:58 am

What oil weight is in the engine? If it's 20-50 I'd put in some thinner oil IMO. Keep your foot off the gas pedal when trying to start it. Not sure what the hissing noise is, you may have dislodged a vac line jostling wires around. The ticking noise may have been one of your hydraulic lifters that finally pumped up once the engine warmed up. The later Bay guys may have better input/thoughts/suggestions.

Wed Nov 18, 2009 7:05 am

There is plenty of normal hissing going around in there, mostly from the intake air plenum in the middle.

Wed Nov 18, 2009 7:22 am

Or you could have a vacuum leak causing excessive hissing.

Wed Nov 18, 2009 7:42 am

Sounds like it was probably your CSV connection.

If you're worried about vacuum leaks, the traditional test is to take a propane torch, unlit, on low, and move it around to all the various connections and see if the RPM's go up.

Some ticking is fairly normal when the engine is cold. Solid lifters will tick because they have a 0.006 gap until the engine warms. Hydraulic can tick until they pump up.

Wed Nov 18, 2009 11:52 am

If the hissing is lasting for more than a moment it is probably in the vacuum system for the brake booster leaking somewhere.

Cleaning all the electrical connections, especially the grounds and protecting them with dielectric grease is the way to go.

I agree that running something thinner than 20W-50 is needed in colder areas, synthetics rock up in the tundra.

Wed Nov 18, 2009 1:08 pm

Traveling Writer wrote:
Quote: There is plenty of normal hissing going around in there, mostly from the intake air plenum in the middle.

Wildthings wrote:
Quote: If the hissing is lasting for more than a moment it is probably in the vacuum system for the brake booster leaking somewhere.

???

I am still learning the sounds of my engine. The hissing is constant. I am not sure if it just started or I am beginning to be more in tune with how my engine sounds.

Wed Nov 18, 2009 1:14 pm

aopisa wrote:
Wildthings wrote:
Quote: If the hissing is lasting for more than a moment it is probably in the vacuum system for the brake booster leaking somewhere.

???

I am still learning the sounds of my engine. The hissing is constant. I am not sure if it just started or I am beginning to be more in tune with how my engine sounds.

Sorry, for some reason I thought you had said the hissing was audible after shut down, and that is why I replied as I did. If it hisses while running it could be any number of things.

Wed Nov 18, 2009 1:23 pm

You can start with the shotgun vacuum leak finding method and use a trickling garden hose on the induction system if you like (don't get the distributor wet and do drive or run the bus for a few minutes after), if you find an area where it runs crappy when you hose it look closer there.
This test won't expose a booster leak though, you'll have to cap that port temporarily and see if it runs better with it capped.

Wed Nov 18, 2009 4:04 pm

Thanks for the suggestions everyone.

busdaddy wrote: You can start with the shotgun vacuum leak finding method and use a trickling garden hose on the induction system if you like

Hate showing my ignorance again, but do I start somewhere in particular? Is there someplace a leak is more likely to be than another?

Wed Nov 18, 2009 4:31 pm

Follow the path the air takes, start where the AFM connects to the S boot, down the S boot to the plenum, where the intake runners connect to the plenum and where the runners connect to the heads. Also do the bases of all the injectors and any hose connections, all along all the hoses infact.

Wed Nov 18, 2009 4:36 pm

Will do, thanks! I just have to get on it before my garden hose freezes up for good!