![]() |
Loud Whistle From 94 Carburetor I've got a nice rebuilt 94 carb on my '52 Customline, borrowed from my brother till I rebuild mine.
Had it on before and it worked great, gave it back to him to try and determine some problems he was having on his '41 PU. Now I've got it back and it has the loudest whistle you can imagine. I'm sure it's a vacuum issue, it's not the line to the wiper motor, all bolts and screws are tight. I've actually had it stop whistling at initial start-up, but it quickly goes into whistle mode. My brother mentioned the possibility of the power valve. I can't leave it like it is, any suggestions for a solution? |
Re: Loud Whistle From 94 Carburetor It could be the spring loaded little disc on the choke flapper is not opening when choked fully to let in some air??? ken ct. PV will not make any noise that i know of even if bad. Does it whistle when the choke plate is full open ??
|
Re: Loud Whistle From 94 Carburetor Could possibly be warped base of body where it mates to the carb base. I've had vacuum leaks there before on a 94 model 59 carb. Creates a very loud whistle.
|
Re: Loud Whistle From 94 Carburetor Had this just this year and
I Traced it with a stethoscope to a hole in my cast base. |
Re: Loud Whistle From 94 Carburetor Quote:
Both the bottom of the bowl body and the mating surface of the throttle body must be flat. File or machine as required. Thicker gaskets there sometimes cure the whistle. |
Re: Loud Whistle From 94 Carburetor Quote:
|
Re: Loud Whistle From 94 Carburetor Great information, suspect base gasket as it's not in pristine condition,
That's an easy solution to try initially. I'll update. |
Re: Loud Whistle From 94 Carburetor Suggest while you have it apart to take a piece of glass and tape a sandpaper sheet to it. Slide the 2 mating surfaces over it until have a uniform sealing surface. Sometimes using just a new gasket will still not seal good enough.
|
Re: Loud Whistle From 94 Carburetor I would go with base gasket as well, a buddy's rpu was making the same noise with strombergs. We traced it to the carb base by pulling the windshield and I climbed over the engine while he drove, the sound was loudest going down the road about 35 mph.
|
Re: Loud Whistle From 94 Carburetor Ralph, I guess no speed bumps in Alaska, or your buddy would have heard some pretty substantial thumps and bumps!
|
Re: Loud Whistle From 94 Carburetor Quote:
|
Re: Loud Whistle From 94 Carburetor lucky no moosie stepped out on road....yikes....the things we do, eh??....done the old ride-the-fender-and-dribble-gas-down-the-carb-while-moving thing back when....and still alive to tell about it...lol....Mike
|
Re: Loud Whistle From 94 Carburetor Ralph, I'd have thought that whistle would have frozen solid, before it got out, at the Pole.:D
|
Re: Loud Whistle From 94 Carburetor It was definitely not the proper way to do it. Don't try this at home kids. But our roads are not that crowded and it worked!
|
Re: Loud Whistle From 94 Carburetor Had the same problem years ago. it was the hidden screw that faces up when the carb is in place. I found it by rocking the top of the carb while the engine was running. Tightened the screw and the whistle stopped.
|
Re: Loud Whistle From 94 Carburetor That screw up from the bottom is really not long enough,use a longer one cut down to just short of the bottom of the hole.Works just fine. ken ct.
|
Re: Loud Whistle From 94 Carburetor Problem solved.
Removed the carb and didn't realize there were remnants of an old gasket on the manifold. Wire brushed that with a small wire wheel in my drill motor till clean (was surprised to discover the manifold mating surface was textured like a cheese grader). Installed a new base gasket.........no more whistle. And nobody needed to ride under the hood. Thanks for all the input. |
Re: Loud Whistle From 94 Carburetor Well that's no fun:(
|
Re: Loud Whistle From 94 Carburetor Darn. I'm west of you over on the peninsula and was hoping to run over for that thrill ride... ;)
|
Re: Loud Whistle From 94 Carburetor Some people pay good money to hear a whistle.........
|
Re: Loud Whistle From 94 Carburetor REVIVAL ::
Have a rebuilt 91-99 Ford carb on a stock 59AB flathead/intake. Truck starts, idles & runs well, but have whistling vacuum leak. 3 times now have started the truck cold & timed it. Parked, it takes about 7 minutes for the truck to warm to the point the carb starts whistling, and it's quite noticeable. Wiper port is plugged. Once the upside-down bolt was loose, turned out the threads there were partially stripped. Epoxied in a stud and used a nut. Checked all surfaces, all gaskets, replaced bottom one twice with new, sprayed exterior with carb cleaner along all seams (no effect), rocked carb by hand (tight- no effect), checked all screws... cannot find the source. If I rev the engine after the whistle starts, it's still there. Seems logical the whistling is triggered by the heat once it warms up. Why/ where/ how? Prior to that the cab base was sweating & very cool while running. Would a phenolic spacer be prudent? |
Re: Loud Whistle From 94 Carburetor Someone told me once that he used a propane torch to track down a carb. whistle/air leak.
With the engine idling crack open the torch without lighting it. Pass the torch around the suspected areas of the carb. If the idle goes up then further pinpointing should lead to the source of the leak. |
Re: Loud Whistle From 94 Carburetor Its possible to get a small vacuum/ pressure gauge as used for checking fuel pressure and air leaks. The vacuum gauge will be a safe method for checking and with a small nozzle on end of flexi hose finding sound not be too hard.
Phil NZ |
Re: Loud Whistle From 94 Carburetor Tried the hose/listening method, and it is difficult. With engine/fan running and the carb so relatively small, there was nothing conclusive heard anywhere around the outside. IMO, a torch gas test would be the same thing- difficult with the fan blowing and even less targeting than carb cleaner shot via a straw. Fuel is running thru a regulator @ 2psi. There is no change in RPM pre- versus post-whistle.
I realize this sort of thing is basically impossible to diagnose remotely, but it's certainly not easy on-scene, either. I'd like to find someone local whose been around flatheads for a few decades... |
Re: Loud Whistle From 94 Carburetor Quote:
|
Re: Loud Whistle From 94 Carburetor SO this HAS to be related to something heating up if it consistantly takes about 7 mins of run time to happen. The aluminum sections of the carb never get this warm, and I believe the cast base of the carb never got 'hot'- it was sweating & cool for most of that time.
Unless it's the intake that somehow is sucking air, but I've not disturbed that and by looks, no one else has since FoMoCo bolted it down. If I install a phenolic spacer- that still needs a gasket on both sides, correct? I'm not driving this in really cold weather (no heat anyway)- icing shouldn't be any issue. Oh- the mechanical fuel pump is still there- I covered all 3 ports while running- no change. Should I plug those ports for any reason? |
Re: Loud Whistle From 94 Carburetor since you say you had a stripped out stud, that would be my first place to start. I'm guessing your carb is leaking between the carb flange and the intake. epoxy is nowhere near as strong as metal....
|
Re: Loud Whistle From 94 Carburetor Quote:
Reminds me of the guys that drove non stop across the country back in the fifttys I think. They had running boards all around the car and could walk around and fill gas, check the engine. I think they even had a set up where they could change a tire while going down the road. |
Re: Loud Whistle From 94 Carburetor (Partially) stripped threads were at the upside down screw, between the bottom & center sections. I JB Welded a stud into the upper section so the sections tightened down with a nut instead of turning threads in the aluminum.
I've read mention of 'thicker copper' gaskets- where are these available? |
Re: Loud Whistle From 94 Carburetor I bet the vacuum was loudest at idle. Goes away when you speed up. Figure that....
|
Re: Loud Whistle From 94 Carburetor Only ever heard of copper head gaskets, not carb gaskets.
|
Re: Loud Whistle From 94 Carburetor Whistle remains when revving motor. Only variable it the truck has to warm up first (7 mins of idling), that's when it starts. One of these clues has to be tell-tale (7 mins, still there when revving)....
|
Re: Loud Whistle From 94 Carburetor Had anyone mentioned a leak around the Throttle shaft? Did you try spraying WD 40 or carb cleaner around the carb?
|
Re: Loud Whistle From 94 Carburetor Sprayed the outside all over- no difference in RPM.
UPDATE :: Took carb off (Ford script 91-99). Tilting it in mid-air and fuel was running out the throttle shaft. This is a 'truck' carb with the manual throttle on the other end of the throttle shaft- that's where it was dripping. I have an 8BA carb, so swapped bases. Put everything back together, truck ran a good 12 mins with no whistle. Problem now is I lost a really smooth idle- it would not idle without throttle and even then ran rough. Adjusted mixture screws for some time with not much in the way of results. Can't drive it this way. Any issue in swapping the bases as far as idle quality? I'm not above sending both out in a box to a reputable rebuilder.... |
Re: Loud Whistle From 94 Carburetor Looks like time for the rebuild.
|
Re: Loud Whistle From 94 Carburetor I did rebuild the carb that was on the truck- cleaned the swapper base but of course there's not much to that. Idled so nicely before, feels like a bit of a sucker punch.
I read someone recommending a carb rebuilder on this board somewhere - anyone recommend anyone? |
Re: Loud Whistle From 94 Carburetor There is a big difference between cleaning up a carb and installing new part and having it completely rebuilt. All the surfaces will be squared up and all the rod holes resized, etc. There is NY Charley and Uncle Max. One specializes in 94s, but don't remember which one. A quick search of the Barn should tell you all you need to know.
|
Re: Loud Whistle From 94 Carburetor Charlie NY is the man you want to talk to.
|
| All times are GMT -5. The time now is 06:36 PM. |
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2026, vBulletin Solutions Inc.