'65 fuel injection

[Rob M.]

Re: '65 fuel injection

one of our members placed two little computer fans (app. 2" square) at the rear of the FI unit at spider high to suck the hot air out of the area below the FI unit. Seems to work a bit, also he had a little electric fuel pump with a little jar of fuel which could be activated briefly after a short stop in hot conditions which worked very well to get the car started...

[Harold W.]

Re: '65 fuel injection

Message for Paul Young. Thank you and others for all the pointers. The only adjustments I have ever made are the idle speed and idle mixture. I haven't touched the "choke" cover position, and the fast idle speed is fine, as cold starting is not a problem. Are there any other adjustments on the air intake side? Does the economy stop fuel meter adjustment affect the idle perfomance? I did get rid of the "blue" return spring and put a stronger spring on it, as the throttle had a tendency to stick. Is there an adjustment for idle position of the throttle blade? I mean is it supposed to close completely or is there a little bypass opening?

[Jerry G.]

Re: '65 fuel injection

Start by going through All steps regarding idle timing Jim and Jerry suggested, don't fiddle with unit adjustments until you are positive idle advance is stable.

[Jim L.]

Re: '65 fuel injection

Does the economy stop fuel meter adjustment affect the idle perfomance?

Yes it will affect the idle mixture but trying to adjust idle mixture by fiddling with it is the WRONG thing to do.

The purpose of the Economy Stop is to set the cruising air/fuel mixture under road-load conditions at hiway speeds.

You should always get the hiway cruise mixture correct by adjusting the Economy Stop screw and THEN adjust the idle mixture using the Idle Fuel screw on the air meter. NEVER the other way around.

Is there an adjustment for idle position of the throttle blade? I mean is it supposed to close completely or is there a little bypass opening?

The idle speed adjustment varies the position of the throttle blade. Throttle blade will always be slightly open at idle.

Jim

[John D.]

Re: '65 fuel injection

Message for Paul Young. Thank you and others for all the pointers. The only adjustments I have ever made are the idle speed and idle mixture. I haven't touched the "choke" cover position, and the fast idle speed is fine, as cold starting is not a problem. Are there any other adjustments on the air intake side? Does the economy stop fuel meter adjustment affect the idle perfomance? I did get rid of the "blue" return spring and put a stronger spring on it, as the throttle had a tendency to stick. Is there an adjustment for idle position of the throttle blade? I mean is it supposed to close completely or is there a little bypass opening?

Harold, Late jumping in here but I see you have gotten a lot of good advise. "Is there an adjustment for idle position of the throttle blade?" You also mentioned you had a sticking throttle issue and solved it with a strong accelerator return spring.
The large brass throttle butterful must be centered in the bore. Failure to have this part installed correctly will result in idle issues and if it's drastically off the throttle may stick like you have cruise control.
Air meter must be off the plenum. Idle adjusting screw must be backed off 100%. Hold the air meter up to a bright light to make sure you have the same gap the whole way around. Hard to explain so I will try again. When the throttle butterfly is installed correctly you should not see any light on the two opposite ends of it. You may see a tad of light where the throttle shaft holds the butterfuly on with two of oval head screws. These screws should have a drop of Loctite on them and be tighten big time as they can work loose and cause issues.
Yes the butterfly should be closed but for all intensive purposes once you set the regular idle it is no longer closed.
Don't forget a part that many do. The fast idle compensator is a much overlooked part. It's purpose is to increase idle when the engine is hot. Test if with a match (yes a match) to see if it will open. Then use compressed air to cool it of to make sure it closes.
You can pretty much forget parades in hot weather if you are using crap fuel. Even with good fuel it's a tough thing to accomplish. A 30-30 cam fuel car isn't the worlds greatest parade car you know.
I had a new 65 in the old days. My Dad complained that it sounded like a poc diesel as he said. So I had the cam lash tightened down. It really affected the power as I recall. So I took it back to the dealers and my friend Tim set the valves cold at 30-30. Although it made some noise it sure did scream.

Why not try the M&H 1 wire set up or go back to the stock ignition points that NAPA has. Also use a NAPA condenser. We are not a big fan of your set-up .
As Jerry mentioned you need to get some better fuel. The phone rings all day with calls like yours and for the most part it's the ethanol. Go to racing fuel or the cheaper 100LL. Or goggle: Pure-Gas.org and click on your state. Then you will see all the stations that have pure gas without ethanol.
You mentioned your fuel unit was rebuilt in the 90's. That's not a good thing either as todays it's a whole new ball game with ethanol, etc.
We actually have better parts today than we did then.
Another forgotten part is the 64-65 starting solenoids. Today there is a kit available to upgrade/rebuild those critters for alcohol.
Back to work. John

[Duke W.]

Re: '65 fuel injection

This is incorrect.

Turning the mixture screw (AKA "Idle Fuel" screw) CCW (out) richens the idle mixture on all Rochester FI units. CW rotation (in) leans the idle mixture.

Mixture enrichment happens because correct adjustment of the Idle Fuel screw permits a small amount of manifold vacuum to supplement the venturi signal which is very weak at idle speeds. CCW rotation increases the amount of supplemental manifold vacuum; CW rotation decreases it.

Jim

Thanks for the correction. I misinterpreted Figs.63 and 65, page 6M-34 of the '63 Shop Manual.

Duke

[Paul Y.]

Re: '65 fuel injection

Message for Paul Young. Thank you and others for all the pointers. The only adjustments I have ever made are the idle speed and idle mixture. I haven't touched the "choke" cover position, and the fast idle speed is fine, as cold starting is not a problem. Are there any other adjustments on the air intake side? Does the economy stop fuel meter adjustment affect the idle perfomance? I did get rid of the "blue" return spring and put a stronger spring on it, as the throttle had a tendency to stick. Is there an adjustment for idle position of the throttle blade? I mean is it supposed to close completely or is there a little bypass opening?

Harold, my 63 throttle blade has a little blade type apparatus that looks like it could give it a little more air and I make sure it is clean from time to time with choke cleaner and then lube with a little Gibbs spray. Also I failed to mention that I use a paper filter versus the oil saturated filter. Do you use the original air filter. Have you cleaned and serviced it recently or at the least checked it? I also have backed out my idle adjustment screw and cleaned it up and sprayed choke cleaner through the hole and reinserted and readjusted it. The only two idle adjustments are the idle air enrichment screw and the idle screw that the fast idle screw resides on. The choke does have a tendency to get carbon contaminated at times but at only 1000 miles I would not suspect that as much. Have you checked the screws on the main control diaphragm to make sure they are snug. Be sure not to over tighten and use a cross pattern to snug. The enrichment diaphragm also could be checked for snugness. Be sure not to over tighten.

[Paul Y.]

Re: '65 fuel injection

I just read about the throttle sticking and I think I would find out why that is happening and remedy that first. Check it with the engine off and see if you can find a bind somewhere. Unhook it from the foot throttle coming through the firewall and try to isolate it etc. Good hunting and let us know what you find. Paul

[John D.]

Re: '65 fuel injection

Paul etal, If you find carbon in your 63 to 65 FI choke housing that's a sure sign that your need a new heat tube installed in your exhaust manifold.
Nothing worse than restoring of those units than going back and cleaning up the messy choke housing, etc that is packed full of carbon.

As Paul mentioned the top main diaphragm cover screwss should not be that tight. Lightly snug the screws down. If you crank them as tight as possible you can bet you caused the round main diaphragm cover to warp. Warp then means vacuum leaks. John

[Fred Y.]

Re: '65 fuel injection

All great advice from everyone. One thing I will never do is use the GARBAGE GAS they sell @ the pumps !! My 65 FI drinks 110 LEADED ONLY & runs sweet at all RPM ranges. Harold , you've got the best so treat her to the best. Happy Motoring !!

[Tom P.]

Re: '65 fuel injection

Paul,
That little blade "apparatus" on the throttle blade is called a Hot Idle Compensator (63-65 models only). It is supposed to open up under severe hot idle conditions to provide more air to improve idling. With an increase in flow, fuel pressure in the nozzle lines will also increase to help push along the vaporized fuel.
Does it work? Maybe.
At what temperature does it open? I don't know, maybe Jerry knows.
I installed a hot idle compensator on the throttle blade of the modified unit that is on the SB400 in my 56. Has it helped under hot idle conditions? Sometimes maybe.