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steve kuiper
08-19-2007, 03:24 PM
i've had my avanti for years and,it seems, i always had to shift into neutral at traffic lights to keep it from killing. this was no big problem until i recently puchase a 1962 lark. the lark 259 runs great in traffic all day long. whether it is in drive or not it still runs great.
that brings us back to the avanti. it is an r-1 w/automatic which has had(at some point in the past) supercharged pistons installed to lower the compression. car runs good until fully warmed up(15-20 minutes) then, when in drive, at a light, idle slowly drops off to nothing. if you put it in neutral idle goes back up. hot idle is much rougher in reverse than drive.
car has new plugs,new cap & wires, timing has been set, new coil, i've re-routed the gas line through water pump(away from exhaust manifold). also i notice the car blows oil once it is warmed up but, not(visibly) when it is cold.
motor,trans, radiator& carberater have been rebuilt. temp gauge is usually between 165-180. i've varied the idle setting from 700-1000 rpms. i've toyed with the richness screws. problem stays the same. car drives down road good. when stopped in drive it wants to kill. when engine is cold it operates o.k. any ideas?

StudeRich
08-19-2007, 03:36 PM
Hi welcome to the SDC Forum, I assume you are a SDC member, if not you can join at a discount right here on the top of the forum main page!

Your R1 Avanti should have a "throttle kicker" which is different than a dashpot, they merely slow the throttle return. The kicker has a vacuum line to tell it when the vac. is high at idle and it speeds the idle as required.

If it is defective or missing, it would cause this. The R1/R2 cam causes the idle to need to be higher than stock 289 (1000-1200) and the need of a Kicker!

StudeRich
Studebakers Northwest
Ferndale, WA

KOOL R2
08-19-2007, 05:12 PM
What are the vacuum readings from a reliable gage?
My guess is that you have a vacuum leak somewhere. If it is OK cold and stumbles when warm it may be a lean condition caused by a vacuum leak

Peter Sant
KOOL R2

PackardV8
08-19-2007, 06:32 PM
Hi, Rich,

Does your Avanti need to idle that high all the time? The manual calls for 650 RPMs in neutral. I thought the throttle kicker was mainly for AC cars.

The other function to check is the "hot idle compensator." This is the spring-loaded valve on top of the secondary bores. From the Shop Manual:

1. After making the idle adjustment (to 650 RPM in neutral), close the compensator valve by pressing on the balve 'button' (not the spring). If the engine speed is not affected the valve slows down the idle speed, the adjustment must be repeated with the valve held closed.

2. See page 8 of the Gasoline section, Fig 10. "If any doubt exists concerning the operation of the (hot idle compensator) valve, it should be replaced."

thnx, jv.

PackardV8

bige
08-19-2007, 08:17 PM
All of the above and try lowering the idle as far as you can and then check the timing. Sometimes the timing is set with idle too high and some of the centrifugal advance is starting to come in. Then when you put the car in gear the idle drops, the centrifugal goes away and the car stalls as the timing retards.

Of course the vacuum advance should be disconnected while you're doing this.

ErnieR

http://i146.photobucket.com/albums/r241/AvantiR2/track.jpg

steve kuiper
08-19-2007, 08:28 PM
these are some interesting ideas. my car does have a.c. it is non-functional. could it still affect the idle? i'm a little unsure as to what the "throttle kicker" is.
avanti will idle pretty low in neutral. vacume gauge in dash is around 15. i'm using the avanti's tach for rpms. so it could be a little off...however the idle has to be pretty high to keep it running in gear. that... or keep one foot on the gas and the other on the brake. i'm not to excited about power braking at every stop light.
i'll check out the compensator valve in the shop manual. the last time i had a question the studebaker forums' answers were "right on target" thanks, steve

bige
08-19-2007, 09:06 PM
Forgot to add "raise idle after timing is set (G).

ErnieR

http://i146.photobucket.com/albums/r241/AvantiR2/track.jpg

StudeRich
08-19-2007, 10:12 PM
quote:Originally posted by PackardV8

Hi, Rich,

Does your Avanti need to idle that high all the time? The manual calls for 650 RPMs in neutral. I thought the throttle kicker was mainly for AC cars.

I could be running it a bit fast so the Automatic doesn't kill it when in gear, but in the real world not the engineer's mind, they do tend to run rough at under 800, I don't know why they called out the same RPM as the Std. 289 with a milder cam, it should be at least 800.

But the parts Catalog does call for the Kicker on all Jet Thrust Lark/Hawks, Std. and Auto. A/C and non-A/C. I do not have my Avanti parts catalog handy right now but I am sure it is the same, my Auto. non-A/C Avanti originally had one, also my R1 '63 GT Hawk.

StudeRich
Studebakers Northwest
Ferndale, WA

1956 Hawk
08-20-2007, 02:16 PM
I had a similar problem with my hawk. The problem ended up being that the valves were adjusted to tight. I had always set them on the tight side of what the manual suggests. Readjusting the valves a little looser fixed all my idle problems.
David

http://thumb2.webshots.net/t/58/158/2/53/30/2596253300089385702FxImoa_th.jpghttp://thumb2.webshots.net/t/54/154/6/1/46/2168601460089385702KmSKeM_th.jpg

PackardV8
08-20-2007, 05:13 PM
Hi, David,


quote:I had always set them on the tight side of what the manual suggests. Readjusting the valves a little looser fixed all my idle problems.

How much on the tight side were you and how loose did you go?

thnx, jv.

PackardV8

1956 Hawk
08-20-2007, 05:39 PM
I figured out the problem when I tried to adjust the valves to .023 cold, at which point the car would not idle at all. My valves were around .025 when I was having the hot idle problems. I now adjust my valves to .028, and have not had a problem since. This is all on a R2 engine.
David

http://thumb2.webshots.net/t/58/158/2/53/30/2596253300089385702FxImoa_th.jpghttp://thumb2.webshots.net/t/54/154/6/1/46/2168601460089385702KmSKeM_th.jpg

steve kuiper
09-07-2007, 01:36 PM
i installed a new hot idle compensator. runs about the same. i wedged open compensator. idle increased a bit. but not enough to make a difference. choke is fully open when hot. so i don't think that is it. engine has good vacumm. hoses are clamped.
only notice two symptoms. when in drive... stopped with brake on idle dies. exhaust smokes(looks blue to me) when hot but not noticibly when cold. avanti runs ok otherwise.

StudeRich
09-07-2007, 02:20 PM
Have you tried disconnecting the Power Brake booster hose from intake manifold and plugging it with a 3/8" bolt. It does sound like a bad unit and or master cylinder, is it using any brake fluid?

StudeRich
Studebakers Northwest
Ferndale, WA

Roscomacaw
09-07-2007, 03:18 PM
I too, would suspect that brake booster. Sounds like (blue smoke) it's sucking a little brake fluid outta the booster. I've experienced this on a couple of cars in my past. One was a Rover TC2000 and the other was a '56 Caddy CoupeDeVille.[:I]

Miscreant adrift in
the BerStuda Triangle
http://images.andale.com/f2/115/106/906179/2006/12/7/truckonhill3.jpg

1957 Transtar 1/2ton
1960 Larkvertible V8
1958 Provincial wagon
1953 Commander coupe

steve kuiper
09-07-2007, 03:44 PM
brakes have not been overhauled in over 10 years. i have bled them a time or two.it is a power brake system. yes it does lose small amounts of fluid on a regular basis. i'll give that a try.