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Tips
Tips

Installing a spare distributor in an emergency

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Bayless said:
Since you can buy a leak down tester for so little (think Harbor Freight) is it really reasonable to try making one at home.....
Click to expand...

Thanks for the response Bayless.

I had bought one of the HF testers and took it back to exchange. The exchange unit was no better so I took that one back. This was about 5 years ago - maybe they have got better? Anyway, that was why I made my own, following plans I researched on the innertube.

Yeah, the compressor is a small one - good enough for a small nail gun or inflating tires but it is questionable for using in this test.
 
Before you do anything, you may consider running some seafoam through the intake as well as some in your oil. A worn ZS carb can really gunk things up, and your low numbers could be caused by sticky rings and gunky valves.
 
Morris, thanks for the suggestion about the seafoam.

I've swapped out the ZS for a new SU and had the head looked at a couple years back (anybody remember the crank nut fiasco?)

That leaves the sticky rings possibility - should I go by the instructions on the bottle?
 
The HF leak-down tester had pretty dismal reviews the last time I looked at it. Maybe it is better now. Obviously you can spend the same amount or more making your own. I was/am fortunate in that I throw nothing away and was able to make my own for virtually no investment in new components.

Adrian, re-work your leak-down tester and re-run the test before making a final decision on doing a ring job. The needle method of making the orifice hole sound good if you have a large diameter needle. If not, the large size (jumbo) paper clips are typically made from 0.040" wire that you could try instead. Smear with a little grease as a mold release and you should be on your way.

I like trying cheap fixes first. Morris' SeaFoam suggestion would certainly be an inexpensive thing to try that might help and won't hurt.
 
Sorry to hear about the HF tester. I got one a couple years ago on sale just thinking I might need it someday. Haven't need it yet though.
 
Just got the bottle of Sea Foam.

Here's the plan:

After warming up the engine, inject slowly 15 ml into each cylinder, every hour, until the bottle is empty. Ha! Should be **** to play tomorrow when I fire it up.

I'll crank the engine over, with the plugs still out, to be sure there isn't any left in the cylinders. Plus I'll do it early when the neighbors are still sleeping.

Hurry and tell me if this is asinine - I'm up to the second injection.
 
I have an assortment of HF tools. Some good, some temporary. I am amazed how some of their products have very bad reviews posted on their own web site. In the case of the leak down tester... 2.2 out of 5 stars from 44 reviewers... on their site (as of 9/18/14). Were I HF and I saw a product had 200 reviews and 2.2 out of 5 stars, I would go to my Chinese supplier and ask for design improvements to address the issues.
Link to HF tester: https://www.harborfreight.com/cylinder-leak-down-tester-94190.html

When I Googled it this afternoon, the first hits included YouTube links. I think it very telling that in the first couple of YouTube videos (links below) one reviewer modified the tester to make it work, and the second reviewer complained that the instructions provided with it did not make sense and were contradictory to common sense.
https://www.youtube.com/watch?v=3RNqoVcPEEE
https://www.youtube.com/watch?v=wEYfQbhtNPs
 
Lots of smoke but no improvement - still "missing" after a 25 mile drive. I'm going to need to think about this.
 
Adrian, not that this necessarily has anything to do with your car's problem, but today I had a smokey start with the Mini. It turned out to be a stuck float valve over-fueling the engine. A few gentle taps on the float bowl to free the float and the smokey behavior was gone, the idle stabilized, and off we went. If your car was sitting for a while it might be worth taking a look at its float bowl.
 
Thanks for that info, Doug. I'll have to investigate. Also, reminds me to take a look at the return-choke mechanism, that isn't working.
 
How about.... proactively install the spare dizzy, get it timed correctly, mark the correct position with paint or a punch/chisel, then store it in the boot. If you ever need it, it should be plug and play.

dklawson said:
I would use a slightly modified method of what Kurt is suggesting.

Turn the engine until you are somewhere between 5 and 8 BTDC for #1 on its firing stroke.
Fit the new dizzy and connect its low- and high-tension wires.
Turn the dizzy body so the rotor is pointing roughly at the cap terminal for plug wire #1.
Turn the ignition key to the run position.
Rotate the dizzy body slowly counterclockwise until you are sure the points are closed.
Now VERY SLOWLY rotate the distributor body clockwise until you see the points open as indicated by a tiny spark.
Lock the distributor down a bit, refit the cap and rotor, and start the engine. Now do your dynamic timing.

In the boot I carry a length of wire soldered to a turn signal bulb. I use that setup as a test lamp when/if needed and can cut the wire off the lamp to make repairs on the road. You can also use it as a static timing light so you don't have to watch for the spark across the points. To do that, modify the procedure above. Stuff the stripped wire on the test lamp into a connector on coil (-)... the distributor side terminal of the coil. With the ignition in the run position hold the test lamp against ground. As above, turn the dizzy counterclockwise until the lamp is OUT/OFF and then a few more degrees counterclockwise. Then SLOWLY turn it back clockwise until the test lamp just turns on. Finish as above by fitting the cap and rotor and carrying out the dynamic timing.
Click to expand...
 
You could certainly paint mark things after you set up a spare distributor. I don't find static timing that difficult and I always have the test lamp and wire in the boot.

If you want to use marks, I suggest paint instead of punch marks. You might change something dramatic on the engine at some point requiring very different timing. Those permanent marks would then be a source of confusion instead of being helpful.
 
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