More on the '60 FI problems

[George W.]

Re: More on the '60 FI problems

Unfortunately all that shows is that it does not appear to be a duplicate of the original. What idle speed is the engine comfortable at and how accurately are the clearance set? feeler gauge, Hot or cold, Initial timing setting (distributor?)

Are you referring to the area below the cam lobes? Both of my other 914 dists. have this "stop" under the points cam lobes which limits the downward vertical movement. Again, the downward movement is great enough to allow the advance weights to "clear" the breaker cam.

If you're referring to the cam grind, then what should I do---it's advertized as the 097. Do I get another cam? Do I somehow "tweak" the engine, valve lash, timing, FI unit to "fit" this cam?

Idles nicely at 850, but I bumped it to 900 once the engine began stalling once hot.

Have checked and re-checked valve lash ---currently 12/18 (hot and cold)--feeler gauge.

Initial timing set at 16 advanced---total at 3,000 rpm is 34 advanced. Use both timing light and vacuum gauge when setting timing.

On another note which may be a clue, when adjusting the fast idle (big screw), there is almost no change in idle speed.

Up til lately, all of the adjustments were made without the air cleaner installed. Now that the air cleaner is installed, the problem is worse. Not enough air flow?

G

[William C.]

Re: More on the '60 FI problems

Based on the cam graph, I'd start with the distributor. There is way too much movement in places it shouldn't be and the pin that serves as a stop should not be able to come out of the slot. The cam may be the wrong place to focus if the distributor is off kilter, and the movement in that one is scary to say the least. Find a shop with a dist machine that can check and adjust to get the distributor stabilized without excess movement and matched to the original curve before you go to any more effort. There are some members recommended on this forum that can help.

[Timothy B.]

Re: More on the '60 FI problems

George,

Looking at your second picture in the original post, I don't know how you can even time the engine with the distributor problem that's shown in that picture. After the distributor is repaired you may not have any more problems.

Could it be possible someone changed parts in that distributor, I can't believe someone overhauled this and gave it back for you to use.

[George W.]

Re: More on the '60 FI problems

Replaced distributor with another and idle vacuum is now 14.

Questions:

How much rpm change should I be able to get from the fast idle screw?

Since I think the unit has been running rich, will a revved up engine "clean" any fouled plugs, or should I just remove and clean?

Going back to the cam specs, is there anything I should try in order to "match-up" the other components to this cam (valve lash, FI unit, timing, ???)?

Thanks again,
G.

[George W.]

Re: More on the '60 FI problems

George,

Looking at your second picture in the original post, I don't know how you can even time the engine with the distributor problem that's shown in that picture. After the distributor is repaired you may not have any more problems.

Could it be possible someone changed parts in that distributor, I can't believe someone overhauled this and gave it back for you to use.

Just to be clear, when you refer to the second photo in the "original" post, are you referring to post #1 (as opposed to the second photo in post #13)?

If so, (post #1), then yes, this is how the distributor was returned to me. There was also about .026" main shaft end play which I have now shimmed to .004".

G.

[Joe M.]

Re: More on the '60 FI problems

Having all this fun, it is ashamed not to go back to basics and sound the old refrain.... have you to checked the accuracy of the balancer marks to the timing tab via a piston stop....

[Timothy B.]

Re: More on the '60 FI problems

George,

Post #1

[George W.]

Re: More on the '60 FI problems

Having all this fun, it is ashamed not to go back to basics and sound the old refrain.... have you to checked the accuracy of the balancer marks to the timing tab via a piston stop....

Hi Joe,
No, I have not.
But, when the timing marks line up, all valves are in the proper position for checking valve lash, so how far off could it be?
Also, I've played with the timing using a vacuum gauge to achieve the best idle, and it always comes back to the original settings via the timing light.
Am I missing something here?

Just to re-cap, the engine/FI unit fires right up, every time, when cold and idles and runs well until temp reaches about 150 degrees.
No gas smell or black smoke from the exhaust--ever. (No white smoke either).
Engine/FI unit will now re-start when hot, but will not idle.
Engine/FI unit still "breaking-up" under WOT and load (revs up great in neutral).
I've replaced the distributor and have better vacuum (14 at idle)

Is it time to re-lash valves to a "looser" setting?
Any other ideas/suggestions?

Thanks,
G

[George W.]

Re: More on the '60 FI problems

Just curious,
Would it do any harm to the engine to re-set the lash on one bank of the engine? The passenger side is easy to get to, but the driver's side is a bear.
If there were a noticeable change in vacuum and FI unit performance, then viola.
If it's a stupid idea, then say so.
G.

[George W.]

Re: More on the '60 FI problems

George,

Post #1

Have you seen the 1st photo in post #13.
Can you tell me what's happening there?
To me it looks like there should be a bushing/washer/seal there, but I've looked at many exploded views of these distributors and see no reference to such.

Thanks,
G

[Timothy B.]

Re: More on the '60 FI problems

George,

I can't comment on a FI distributor but on a tach drive distributor the weight base cam sits in a cup (for lack of a better word) that's part of the points plate, I don't see that in your picture #1 post 13. Inside that cup I have seen a thin felt washer and I have seen some without the felt washer. I don't think the felt washer is your problem with that much up/down play.

There is also a felt washer below the points plate that sits on top of the oil seal.

[George W.]

Re: More on the '60 FI problems

Pulled plugs to inspect. They are dark, almost black, with brown color on the end of the ground electrode.
Did another compression check--All cylinders range between 175 and 180 psi.
For what it's worth, the 283 engine is .060 over, and is fitted with flat top hyperkinetic pistons.

[George W.]

Re: More on the '60 FI problems

George,

I can't comment on a FI distributor but on a tach drive distributor the weight base cam sits in a cup (for lack of a better word) that's part of the points plate, I don't see that in your picture #1 post 13. Inside that cup I have seen a thin felt washer and I have seen some without the felt washer. I don't think the felt washer is your problem with that much up/down play.



There is also a felt washer below the points plate that sits on top of the oil seal.

Thank you for the info.

I was hoping that the re-builder was following this thread and hoping that he would contact me privately with some insight---but have not yet heard from him.

Well, another 11 1/2 hour day spent gathering/exchanging info, changing out distributors, testing, double checking, taking a test run, etc., etc. and no change to the operation of this engine/FI unit.

I'd be scared to add up the hours I've spent trying to figure this unit out. (gotta be in the hundreds of hours).

I've contacted the re-builder, and couple of other re-builders asking if they would "repair" this unit. So far, no response?

Owner of the Vette is going crazy: he comes by and sees his newly repainted, new chrome, stainless, new interior, beautiful Corvette and he can't drive it.
Thinking of putting a carb on it for now so he can enjoy the car while I figure out this problem.

Oh well, it's whiskey time.
G

G.

[William C.]

Re: More on the '60 FI problems

Keep in mind that by now, you likely have trashed a set of plugs, while changing them, it would be a good time to check the resistance of the wires from the distributor. Also, what rotor are you using. The current rotors are much shorter than the OEM units and the FI engines need all the spark they can get. Back in the late 69's when my daily driver was a '58 FI with Hi-comp 327 and 30-30 cam, a set of plugs was good for about 3000 miles before falloff in Perfoarmance, I used to pull them and give them to friends to put in their 283 2 bbl Impalas so I could keep the FI running sharp!

[George W.]

Re: More on the '60 FI problems

Keep in mind that by now, you likely have trashed a set of plugs, while changing them, it would be a good time to check the resistance of the wires from the distributor. Also, what rotor are you using. The current rotors are much shorter than the OEM units and the FI engines need all the spark they can get. Back in the late 69's when my daily driver was a '58 FI with Hi-comp 327 and 30-30 cam, a set of plugs was good for about 3000 miles before falloff in Perfoarmance, I used to pull them and give them to friends to put in their 283 2 bbl Impalas so I could keep the FI running sharp!

Good stuff Bill.
i've changed plugs twice now, but with the price so low, why not throw in another set.
i can look it up , but what should I be seeing for resistance in the wires?
not sure on the rotor; what brand/type should I get?
g