Distributor Refurb

Hi Everyone, I have a "Dino" project car and trying to get it running cleanly. Cyl 5 and 6 are wet plugs and not firing. Confession! It's a Fiat Dino but there's little activity over there and I know from my 308 how much help you get on Fchat.

I took the distributor off as too cold to work outside and I want to check it out. Check the advance works but mostly check out everything else. Questions are
1. Point contacts are way out of line but how do I get the "spoked cover off to change? Pullers?
2. how do I check the advance? I can't get into it and wonder if there a video guide or similar on disassembly
3. Is there a EU supplier recommended for value and service without bad Chinese quality.

I appreciate any help. Thanks in advance

Andrew
8 I

 

https://www.ferrarichat.com/forum/threads/r1-r2-ignition-phasing-6lobe-cam.221650/#post-138187462

https://www.ferrarichat.com/forum/threads/dino-246-ignition-advance.224628/page-3#post-139985132

these posts by daviekj should help you out but to do it accurately you really do need a sun machine to check the advance curves. Most now run with slightly more advanced ignition.

Check the heat range of your plugs, some advocate the EVIX NGK plugs but i dont like them as they tend to foul very easily. I use the NGK EP7ES.

Wet fouling sounds more like a over rich condition on those two barrels, bad HT leads or a cracked dizzy cap.

Tony

 

Thanks Tony, I swapped the BP6 plugs around and problem stayed. There's what looks like new Superformance leads. But...i did clean the dissy contacts and rotor arm a day ago and the problem was worse! so there is definitely a distributor issue and my cleaning wasn't good. While I have the distributor off I wanted to check it.

Another thing is when it turn the shaft its like a generator and it doesn't spin freely but clicks noticeably 6 times per rev. Is this notchiness normal?

 

Andrew, try photos in post 56 of https://www.ferrarichat.com/forum/threads/rebuilding-a-dinoplex-aec103a.276251/page-3#post-139967459 For the distributor disassembly.
If you have the points still in place, you will feel the 6 notches on hand rotation (distributor out of car). If you have the unit out, suggest check bearings while there.
Kevin

Tony, I gave up searching for a good second hand Sun machine... would have been nice though...

 

BP6 are slighter hotter and should be Ok, BP7's are good and slightly hotter than the manufacturers equivalent ie BP8. Good idea to fully service the dizzy while its out, the clicking sound is just the points opening and closing.

It doesnt sound like the dizzy is at fault otherwise you would get a problem on another cylinder apart from 5 & 6. ie firing order 1,4,2,5,3,6.

Make sure the new leads are pushed home firmly into the distributor cap, the SF leads have a really tight fitting shroud and some need a little adjustment to get them to fit properly. I just bought a new set from them and it was a real pain to get them pushed into the cap properly, a cracked cap can lead to a short to ground thus losing the spark to those 2 cylinders. With a new plug fitted to the # 5 & 6 leads and ground to earth, do you get a healthy spark.

For me i would look at the carbs to those cylinders first, check float levels, mixture settings and especially the accelerator pump circuit to ensure no fuel is dripping from the jet.

With new plugs fitted do they foul up after a run or when left idling. You may need to dig deeper with a compression test.

tony

 

I've been using the plugs suggested by Mike Elliot at Superformance some years back. They are NGK with the multiple electrodes. they seem to work well, and not be prone to fouling. Also, the Dinoplex AEC-101 (big brick) helps it run smoother etc. The distributors are quite the little pieces of machinery. Take your time and study carefully. The advance mechanism is prone to wear and corrosion. Check for divets worn in the drum. This can be tuned with them to some extent, so long as the action is smooth. You want it stable at 500-600 (distrib rpm) so idle is consistent. Then start to advance consistently for best throttle response. A synchrograph is essential. The Sun unit is very good. To remove the top bearing support, I use a small gear pull. It doesn't take too much force. Generally just above what can be done by hand.

As others have mentioned, carb's must be good. If the distributor is set up on a synchrograph, you can usually just align it and get underway checking other bits.

 

Your write up is excellent and a valuable post for future reference Kevin, I sent my dizzy to Initracing and they set it up perfectly with slightly better advance curves for HC pistons. A static advance of 10-12 degrees makes starting so much better.

 

Thanks Guys. I totally agree with carb needs doing. Choke on 1/4 is stuck off, so they're obviously needing work.

No Dinoplex any more but a PO put Superformance Super4 box on it.

Spark on 5 and 6 is orange, weak and doesn't even jump to the tip but to the edge. One set of points doesn't even align or overlap properly.

The noise is not points as its at 5rpm when turning by hand. Its coming from inside. For some reason the mp3 recording of the noise won't upload. Rotating is the opposite of smooth, moderate force to get the shaft moving as if its at a stop and then it flies around to the next stop 60 deg later. At each stop it makes a deep noise.

I feel bad advance is the noise problem
I feel points are the spark problem.
All I need to do is try to make a puller now

 

Hi Andrew, I just striped my distributor down and used a windscreen wiper puller bought from eBay for around £6 to remove the upper bearing.

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This is not the best alternative. It does not deliver much power to the spark.

 

I don't think the Super4 is the problem. Yes, there are better alternatives available now, but the Super4 is perfectly OK. I had one in my US Dino for at least 18 years and never had a problem with it. Also, a problem in the ignition box is unlikely to show up only on two cylinders.

Andrew McCrae seems to be on the right track by looking at the distributor. To me, though, the fact that he has weak spark mainly on cylinders 5 and 6 indicate a problem somewhere around rotor/distributor cap/ignition leads. But of course points also have to be operating correctly.

 

You're right. The problem for these two cylinders must be somewhere else. That's why it's also not a question of the type of plugs.

Are the plugs on 5&6 firing at all? If not, I'd look on the distributor and the leads. If they are firing, but have poor combustion, I'd also look at this carb.
If this is fixed, I'd still replace the ignition box. Best choice would be a Dinoplex, but a Winterburn, MSD or Bosch would do the job cheaper.

 

That photo shows the right idea of neat and tidy. I was going to possibly try today to create a simple puller with a few bits of steel and tapped holes on a lower cross piece under the bearing. Patience for eBay is thin and post into Ireland is mad at the moment with Brexit causing customs delays.

 

As you have the dizzy off its a sound idea to completely rebuild it, there are some good tutorials for members detailing how to go about it. Use the search function and look for distributor rebuild including Corbani's corner. You need to be careful how you re-assemble the weights and springs though. I would still recommend you find someone with a Sun type machine to set it up once fully rebuilt though, this will ensure the points are phased correctly and the advance is working as it should. IMO there is no need to fit the 4 spring points sold by some suppliers, the 3 spring type is more than adequate. Beware the points sold by some are very bad quality and some fiddling / adjustment is required to make sure they operate correctly. I had to bend the arm slighlty on two sets as the points face were not even parralell to each other.

Not to sure what the noise is, it sounds like the points but spinning it at 5 rpm does not actuate the bob weights, they kick in around 750 rpm. or it could be the pins are badly worn.

do you get a good spark on the other 4 plugs using NEW plugs, if so then the problem is elsewhere?

The Super 4 ignition works OK for the Dino engine but better ignition systems are available if you want to upgrade and can be retrofitted in the old MM box. From what others say it does improve but i have the S4 box and it works fine.

A small bearing puller is ideal but it can be pulled off by hand with very little force.

Ignition related problems are an arse to identify and difficult to diagnose but working in a logical manner usually identifies the problem.

Tony

 

The distributors are almost always totally worn out, especially on Fiat Dino's that most of the times have more than 100.000km on them.
I've rebuild many of these distributors and i have all the parts. Basically it does not make sense to try to repair them partly because everything from pins to advance mechanism to 3-lobe cam etc. etc. wears. Just put all new parts in there, set it up on a distributor testbench and you will enjoy it for many years without issues.

 

Stefan, thanks for posting. I enjoyed that. Informative tests for chatters to see.
Green with envy on your test machine...
Kevin

 

That's great Stefan. I'm in agreement on the rebuild and have on order all the parts excluding the weights and springs as I got frightened by the tales. I don't have access to a distributor machine here in Dublin and I've no idea how to get access to test with different springs. (as an example my 2 nearest repair shops looked blankly and here in Dublin the two largest parts suppliers looked blankly at me when I wanted to get a spark tester.

I think Kevin, you setup without a sun machine? I've looked at so many posts I've lost track. I am wondering if I can escape the need for the machine.

Thanks Andrew

 

Doesn't have to be a 'Sun' machine. You just need the functionality to know the advance for a given RPM, where the advance occurs, and alignment of the points to give evenly spaced spark. There are a few makes out there of dizzy machines.

 

What i've noticed with these Dino distributors is the following:
-You always need to replace/repair the 'base cup' because the pins from the advance mechanism leave indentations. An economical repair is to TIG weld the indentations and machine it afterwards on a lathe.
- The 2 bearing pins on which the advance weights rotate are always worn. This causes to much play between the pins and the advance weights and unexplainable behaviour of the mechanism.
- The advance weights itself are mostly worn and the springs loose pressure. From an economical point of view it does not make sense to leave them in place because when you set it up on a testmachine you will need to take the distributor apart 10 times to add shims to get it right.
- The 3 lobe cam itself is actually quite good but when the advance mechanism is worn, chances are that the part that guides the weights are worn and than it needs to be replaces as well. But in 25% of the cases this part can still be re-used.

The main reason to set the distributor up on a testmachine is not even to check the advance curve. Yes that is important, but more importantly you can check if all 'cilinders' fire evenly every 60 degrees and you can set your rotor phasing perfectly, the 2 breaker points in relation to each other and you can set your dwell perfectly. Dwell might not be that important when you use the original Dinoplex or an equivalent CDI system but i like to have it correct anyways.

It has happened to me many many times that i've placed new parts inside a distributor and that i only noticed that there was a problem with the new part until i tested them on my testbench. Just a small tolerance problem with a 3-lobe cam will set you off 3 degrees easily, you will never notice this without a test bench but you will run your car with 6 degrees of difference in ignition timing between cylinders. And that is just one example of many problems i've seen (with new parts as well).

If you can't find anyone locally to help you, and you don't mind shipping it, i can help you with it.

 

Andrew,
First thing to do is ensure your distributor is in good condition as per others comment above. Sounds like you are on that path. Ie. Bearings, advance weights free to move and minimal wear at pivots and piston contact points (as per Stefan,s comment above, see photo of this in thread path below). If that all looks good, the distributor dynamic advance can be observed using a car timing strobe (distributor on car). Easy to set up and check advance behaviour consistency with work shop manual. What is more tricky is solving any advance issues, eg springs, piston spacers. Without a Sun machine, it’s is time consuming and not ideal, as each new set up requires reassembly to car and re-strobing. None the less this is the approach I took in https://www.ferrarichat.com/forum/threads/dino-246-ignition-advance.224628/#post-138254922
However, still not sure any of this will address your original issue with just no. 5&6 sparks. Did you rule out the distributor cap as potential cause?

Lots of others here more expert than me on this.

Kevin

 

Ah, this is great gentlemen. I expect it could take a couple of weeks to get my bits. Stefan I will order more parts as you suggest. I truly appreciate your kind offer but will try the DIY method first. Patience may get me there.

Thanks a lot.

 

Stefan, is there a supplier of parts in the EU that you know of please. Brexit makes things incredibly slow and expensive these days.

 

So bearing is off and needed the windscreen puller with force. . [emoji16]. Everything stuck together with black glue that used to be grease.
Question now is how do I get this off, puller I have won't budge it, I need this off to get to the circlip that allows full disassembly.
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Andrew,
I see from your photo you have removed the distributor case and therefore exposed the advance system for servicing. I have not removed the base assembly in you photo above, so can’t help on this part. What is the reason to disassemble this part, does the lower bearing need replacing?
Kevin