Distributor Springs Advice

I was able to purchase advance springs at a local Speed Shop but that was several years ago.

The distributor mechanical advance should offer somewhere around 24 degrees advance. With an initial timing set at idle around 8-10 degrees this would give you a total of close to 34 degrees when fully advanced which should happen around 3,000 RPM with a very smooth introduction of timing as the RPM climbs from idle to 3,000.
If the initial timing really is set at -30 to make this engine run the advance mechanism was most likely rusted in one position and not working at all. Free it up, get it clean and lubricated and the new springs should have you good as new.
Mark

Thanks Mark!

I think the PO had it set so there (~30 on initial timing) so it would run good at top end, but it still wouldn't go past 4000. I set the timing back down to 10, and when I got up to higher RPM's, the engine made a very strange noise, and it did not like what I had done to the timing. So, I just keep it to around 2000-3000, which is where I run most of the time anyway, and it runs fine.   

I did put the vacuum gauge on it, and the needle really jumps around quite a bit, and is not steady. Hopefully the with new springs, it will settle the vacuum reading down too.

I did hit the weights with PB Blaster, and they are free. Hopefully all will be good with new springs.

Appreciate the advice.

Dave

When the little spring breaks, your timing which was probably properly set at about 10 degrees BTDC at idle, jumps up to about 30ish with the little spring having no ability to control the advance. Your total advance won't be much over that (maybe a few degrees) as the big spring starts to control the advance.

On your Prestolite the big spring isn't in the picture till around 4000 rpm (because of those oval shaped ends) not the 3000 mentioned above.

You won't find the original springs pretty much anywhere these days and you can't slap any old springs in there. In other words don't buy springs for an AC Delco distributor and expect good results.

The Hillman I mentioned works good and pretty closely duplicates the stock curve.

Fixing this really should have no effect on your top end rpms, it just gives you the stock curve with the same amount of total advance

Thanks Ken, I think the Marine guys stayed really conservative and your right it takes work to update it.

Andrew......Interesting. My boat also was having low speed stalling and idling issues, and I was wondering if it was due to the timing issue.   My marina guy ordered some springs from NAPA. It will be interesting to see if they are actually Prestolite springs. I can't believe these little buggers are such a PIA to source!

The ebay listing is for 10 springs, so not a horrible price, except I only need one... There is a local Ace hardware store that has a very large selection of small parts. They might have small springs but will one be labeled as a # 119? Maybe, maybe not. Total guessing game.

Sure, I'll spend $30 for an experiment for the good of the forum, worth it for all the problems i've solved here.

I did not check the timing up the acceleration range. I did check it Saturday at 1000 rpm and it's right on 10. I've checked the timing during previous seasons and it's alway been around 10. Is there a chart that tells me what is should be as I step up the RPMs?

I'm wondering if there is a simple measurement to compare springs of the same wire size and length? maybe hanging a couple of different weights on them and measuring the extension. I will spend a few minutes on the Net and see what's been posted.

Hillman provides the cabinet with drawers to the hardware store usually.

The drawer that say 119 has the springs sometimes in a bag, sometimes loose.

The dimensions are shown earlier in this thread in a picture.

So.....not too much of a guessing game

If you don't check your advance curve and total advance with the present springs, how will you know if the MC Parts Depot springs give the same curve and total advance if they're not an exact duplicate of what you have?

You can have the same 10 degrees at 1000 and everything from there up could be different. I'd check it every 500 rpm starting at 600 or whatever your idle speed is, 1000,1500 and continuing up and write it down. You won't find any numbers or graphs from PCM showing the curve, but I might know a backyard hack who'd have some numbers to compare with yours

I did see the specs on the #119 and found the same info on-line. It has a weight rating of 10.18 lbs. Which might be the same spec as something called the "working load" or it might be the " initial tension".

If my current spring is still giving me the originally specified advance curb then I don't need to replace it. The problem is I don't know if it is. it's pretty rusted and I would expect that to change it's properties and by extension, the advance curve.

i'm probably diving too deep in the weeds, but. If someone with a small distributor spring in good shape can give me the following information I might be able to use a fairly complicated online spring calculator to figure out all the properties and see if they have a similar spring in stock. I would try it with mine, but it's all rusted up.

Need the following: Wire diameter, overall spring length including the hooks, outside diameter of the spring, number of full coils (not counting the half coils at the ends), And the amount of weight you have to hang from the spring to cause light to just start showing between the coils, in other words just when the spring starts to extend. I played around with the calculator some and I'm guessing that weight is between 5 and 10 lbs. A picture would be great as well.

Meanwhile I will pick up a #119 and install it to see what happens. Probably be a few weeks till I do, we've got plenty of skiing planned and I don't want to take the boat out of service.

[QUOTE=MrMcD]   If the spring is rusted it is weak and your timing will come in early. /QUOTE]

In that case every distributor spring out there is weak, since they all get rusty

And for Andrew, I really don't think the distributor has anything to do with your idle issue right now. You still have the same 1000 rpm timing you've had in other years.

I tend to think you're on the right track with carburetor idle adjustment and checking for vacuum leaks like mentioned in the other thread..

Ken knows his springs! He also knows a thing or two about the curves as he helped me get things back to normal on my 78 commander about a year ago. Thanks again btw!

Ken....I appreciate you posting those numbers, and your help on this situation. I stopped by a NAPA today just to see what the response would be when I asked for these springs. Pretty much the same as AZ or OR....ie....what year, what make, what model, what engine, etc, etc.

Stopped at ACE on the way home. Took me 30 seconds to locate the Hillman bin. There was good ole #119 just waiting for me (three actually), so I grabbed 'em @ $1.69/ea.

My marina guy said he got me some springs too from NAPA. It will be interesting to see what those are since NAPA had no clue when I asked. Well, it's nice to have options anyway. I may throw the timing light on it to see what kind of numbers I get.

andrewmarani wrote: Compare the Napa springs to the # 119. Tell us how they compare in length (overall), number of full coils and diameter. If you have a spring fish weighing scale, pull just hard enough to cause the coils to open up slightly and tell us the weight for each spring.

Umm..........you should do that yourself at least for the Hillman, you'll go bug eyed trying to count the full coils on the Hillman. and the scale should be for miniature goldfish or something like that

I think you may be right on the gap changing when you put things back together.

I also think at least from looking at the picture that the NAPA spring is longer and a lot beefier and will give a slow curve and won't let you get to full advance very easily

Could be that I'm still bug eyed from trying to count the number of coils in the Hillman spring

TRBenj wrote: I’m sure you realize this can all be done on the trailer?

I do realize that, but, I wanted to use it today and also see how it did on the water. Nothing like an in-water trial once "fixed". But, today's conditions were less than ideal for doing what I was doing, plus the wife was helping me. Next time.....the trailer!

If you look at page 9 of the manual in the link from the reference section here on CCF you'll find the timing spec for the screw down cap as 10 degrees and the clip down cap as 6 degrees.

Reading the notes, they limit you to 30 degrees total advance with those numbers.

They're different because the slots in the timing plate are different lengths.

The screw down distributors have a white nylon type plate with shorter slots.

That's probably what you have. being an 87

You'll also see a note on page 9 referring you to page 6 of the manual for timing instructions on 87 octane that say to reduce your settings by 4 degrees.

Everybody will start yelling now that those are ultra conservative numbers..............yell at PCM and Ford, not me, they came up with them    It probably was to cut down on warranty claims while still getting OK ish performance

Myself, I'd set it at 10 and check total timing.to be about 30 with the Hillman spring and the heavy spring installed.and tweak things from there if you want to.

Note that they say 30 degrees max at 4400 rpm.

Depending on your prop, you may never see 4400 rpm

As far as your timing question, setting timing in neutral is perfectly fine but the idle could be lower like around 650 to 700 rpm , which when you put things in gear will drop the idle down to 600 or so if the carburetor is adjusted right.

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