And water in the petrol I suggested earlier but was said wouldn't cause total failure to fire just poor performance?

 

Well, a couple of months or so ago, I tried to fire my trusty lawn mower.
Fire a bit on Ether, then go silent. Dumped it's old "stabilized" E10,
siphoned off some more from the Jaguar and it fired right up. Excuse gone, "pasture" mowed.


My present "excuse" is that we are having "clear the air day". compounded by smoke from the Big Sur fire, circa Monterrey.


Reminds me of my early LA days.


A couple of hours in the shop after in door chores is about the limit.
102 F the last couple of days.


At one time, OK, so what. No longer, I am aware of my limits. Seniors, like me, don't fare well in 90 F+


Carl

 

Recleaned the spark plugs and rechecked the lead plugs from the dist. but still no joy.
lot of healthy rev'n but no firing. try different battery and new fuel next as I can't think of much else unless the engine is entirely seized beyond my repair and i just don't know it, oil level seems good.

 

No, probably not. But, the end of my 4.2 cranked heartily, but not a bang....


Compression test, "0" in all holes. This after a huge over heat leading to a stall. 4.2 done for.


If you have compression, it will run.... If not, not a chance.


So, now all you need is fuel and spark, each in the right amount and at the right time.


Spark: Use a strobe timing light on each HT lead. Light is good, dark is bad. If no spark, jump 12v from the battery to the coil + post. crank. Firing up very likely.


Fuel. start with fresh fuel in a tank and try. If no bang. remove each spark plug and prime with a bit of fuel in each. Fires briefly, good.


Baby steps> do each and report back....


Carl

 

Petrol sample. I could have pet fish in this 1 liter sample jar. Time to drain the tank I guess.

 

And the carbies also.

 

Had cleaned all the spark plugs two weeks back and they smell of petrol now so I assume this suggests fuel is reaching them. Then that takes me back to electrics, as I am certain fuel is getting thru and is clean now.
Could it be that the battery is not powerful enough to kick the engine even tho it is showing 14.1v? Maybe amps dropped too low? Just dead.
Could it be the alternator? Not sure at which stage this kicks in, might it be faulty? But expect that isn’t relevant to ignition.
Back to distributor. Perhaps the spark coming off the dist. Just isn’t enough, the one from the coil to dist is powerful but what I think I see at plugs is not as great.
Tested each cylinder for compression today and each one blows/sucks with ease when plugs out so assume no issue there.

Back at a loss again

 

Whew, that "fuel" could not be ignited by lightening.


1. Puffing at the cylinders is good, but not precise enough. Use a guage.
An inexpensive one will work.


2. Is the spark from the coil to the distributor cap sharp and blue
or yellowish and wimpy? Do you mean that the spark from the cap to each cylinder falls into the yellowish and wimpy description. Not good enough to fire the fuel charge. May not exist in a compressed air cylinder. Investment in strobe light would help track the issue.


3. Examine the inside of the distributor cap. Cracks?? Worn or non existant center button? Each terminal inside and outside. Clean and tight.


4. The rotor. Contact to the cap center. If a spring, lost it's spring???


If all that checks out as you have fuel, and it still refuses to fire up, report back for more help.


For clarity, refer to starter action as cranking and engine "revving" as
running.


Ie, it cranks, but does not run on it's own...


Goal in any IC engine. fuel, spark, and compression, each in the right amount and at the right time.


Got my one banger lawn mower that refused to "run" by checking each of these elements out and fixing the bad. In its case, it was stale fuel.


Carl

 

definitely rule out 3 and 4 as cap and rotor replaced earlier in this 'trouble shooting' process for certainty. will try and re-check items noted in 1 and 2 to make sure I am not missing anything.
as to what I am hearing, re clarity, not totally sure. the starter is doing it's thing and the electrics come to life with a rev rev sound like when a battery is flat but it doesnt fire. the battery shows 14.1v.

 

Battery should be mid 12 volts not 14.1, do you have a charger connected? If you have any battery doubts why not jumper up another one to test?

Maybe try some "start ya *******" spray to see if you can get a sign of life? to point you more toward spark or fuel.

Had the distributor been out for any of the work? just wondering about timing.

 

both my batteries usually show between 13.1 and 13.6 when fully charged. yes, have been trying to obtain the use of another 'known good' battery in case.

distributor has never been removed, I understand it can be complex to reinstall and want to avoid that unless it proves to nexus of the problems.

 

To clarify. The starter in your engine cranks heartily! True or false?


However, the engine does not start and run when the key is released from the crank position to the run position. True or false?


No comment from you yet on the quality of the spark at the spark plug. True or false?


No use of a compression guage to determine engine health. True or false?


No use of a strobe to establish the existence of spark at the spark pugs. True or false?


Answers may clarify just what state your engine is in.


Carl

 

I can 100% assure you, from a rather exciting experience in a light aircraft, that water can stop a petrol engine stone cold. It just depend how much arrives where in what concentration.

 

yep they will read high disconnected and then drop back when you connect them up and a bit of current flows, as you drop voltage within the battery. All academic really , the main point is you feel they are fully charged.

Wasnt suggesting pulling the distributor, just trying to understand if it had been out and the likelihood of timing as an issue.

 

"The starter in your engine cranks heartily! True."
"engine does not start when the key is released from the crank position to the run position. True."
"No comment from you yet on the quality of the spark at the spark plug. True or false?" Checked again tonight in darkness and clearly getting strong archy blue spark which fades on each ignition attempt as battery drains until yellow.
"No use of a compression gauge to determine engine health. True."
"No use of a strobe to establish the existence of spark at the spark pugs. True."

Battery only lasts around 4 or 5 ignition attempts before it is 'below' required voltage.

Plugs smell of fuel so fuel vapor is getting thru.

Rechecked all electrical terminals again today to be sure. If it's not the distributor then i wonder if something else elementary has slipped passed or come unstuck since the primary problem starts three weeks back.

 

1. Inadequate compression on cranking to run!!!!


2. Poor batteries?


3. Dragging starter.


Should survive many more craning efforts than that!!!


1. Must be resolved or any other efforts are for naught..


Extra:


As you have two batteries, charge each fully. Gel celled units need "smart" chargers. Ordinary ones will not fully charge gel cell units, ala "Optimas".


Use one to crank the engine.


Use the other for ignition. Battery + to coil +. Battery - to a bolt on the engine nearest the coil.


Try some more...


Carl

 

compression test about 4 months back cyn1 120, cyn2 & 3 150, cyn4 120, cyn5 130 and cyn6 140.
(hard to do test with battery fading so fast, results varied)
start of week with AA 530 cca battery I had cyn1 105, cyn2 115, cyn 3 115, cyn 4 100 cyn 5 110 cyn6 95
put in new 600 cca Century battery today but results still inconsistent.
as battery takes successive attempts to start it wares down. not as far now.
so
cyn1 was 120 cyn2 was 50 then 115 cyn3 was 120 then 135 cyn 4 was 95 then 105 cyn5 was 125 and cyn6 150.
so in a way without the engine going the results are neither scientific or useful I suspect.

 

Although your compression test is a bit shaky, it indicates just enough to run. Cyn 6 is the only one with really decent numbers!!


One thing left. A dragging starter. From your description, it quits cranking far too soon. Or another way to say it, too much battery drain... Not enough left for ignition.


You've not hooked up one charged battery to crank and the other to the coil for ignition. Why?


Carl

 

With all this cranking and testing you now have bore wash.

Squirt a shot of engine oil, NOT a flood of oil, about a teaspoon amount, into each cylinder. This will assist the rings to seal until this thing starts and rebeds those rings.

You need to sort why the spark is SO weak at the plugs.

I have hundreds of questions/suggestions.

I will assume you have a "volt meter"??.

Turn ON the ignition, probe the +ve of the coil, WHAT volts are you getting?????. This will assist me to understand IF you have a ballasted ignition system, or not.

With that probe still attached to the coil, crank the engine, WHAT do you have now??????.

Once you tell me that I will continue.

 

You've not hooked up one charged battery to crank and the other to the coil for ignition. Why?
done today, no result.