Well wizards, heres one to test you're knowledge out.

As a continuation of 'Coughing and farting engine" on a previous post, it has turned into a cant start the bastard/bitch. the culprit is a 1200 40HP engine.

I've replaced:
leads
points
rotor button
dizzy cap
condensor
plugs

All the gaps are correct (plugs and points). Fuel delivery is fine as is the coil's output. The timing is correct. the mixture is fine erring on just a little bit rich.

I tried to push start her down a hill and the second i dropped the clutch to get her started, a pop of small flame came out from the exhaust, but the engine did not start nor did it even feel like it was going to start.

I checked the position of the rotor button and dizzy body to make sure it was firing when it was supposed to -- and it too was correctly timed and installed. (so not a stripped dizzy pinion gear then i suppose) Since i got a pop and a flaming fart from the engine (only once) it meant that i was getting good spark and fuel into the cylinders yeh? SO WTF IS WRONG?

someone please help

Do u have someone to help you??

Are you getting spark??
Have you SEEN a good healthy regular spark???

Sounds timing related.

I know u have replared those things - but are they working??
I have replace new points with duds.

Cany you see fuel when the accelerator is pumped???

Are you getting 4 even compressions when u turn the motor by hand??

"a pop of small flame came out from the exhaust"... sounds timing/distributor related

Are the leads on in the right order ?

yeh, the leads are on in the correct sequence and the spark should be fine coz i got the flame from the pipes... i also tested the spark with an old plug held up against the engine block and the spark was fine. Also conducted the same test with just the coil lead and the spark was jumping a gpa of about 1/8 inch so it was all good... yup blue spark!

any other suggestions? (besides getiing another engine?)

I am assuming you HAVE good compression on all pots. Take off the rocker covers & rotate the eng by hand & watch what the valves do. As it cycles, you'll see the inlet go down (suck) a bit of a pause (compression=bang) & then the exhaust will go down (blow). At each bang point, where is the rotor pointing to? eg when no 2 is on compression, does the rotor line up with no2 terminal on the cap?? Then is the lead from no2 actually going to no2 plug? Do the same for all 4 pots & report back.

You havent had the engine apart have you ?

If you have, check that the rotor is pointing at the right lead at the right time, because I have heard of people putting the dizzy drive in 180 degrees out, which causes funny timing problems like that.

Ask a silly question - full tank of fuel and good fuel pump ?

One time we were out in my cousins car and it stopped. We tried to start it and we got a backfire out of the exhaust and a cool flame burning in there. We checked everything and it all seemed fine.

It ended up being the distributor clamp. It wasn't perfectly flat, and was holding the distributor up in the air a little. Most of the time the drive dog would be engage, but every now and again it would spins around a lap and engage again. So basically every now and again it would fire whenever it felt like it. When you took the cap off and rotated the engine the dog stayed engaged, and it all looked fine. but it was only when you tried to start it that it would slip. Something to check out anyway.

same prob i had on our 1500 notch!!! we solved it by not having the leads in the right order on the dizzy cap!!! check where ur mark is on the dizzy for #1 cylinder and go from there!!!
cheers
rhys

Hate to say it but I bet it is your leads.

What dizzy do you have ?

Take out plug 1 and put a screw driver in the hole, turn the engine over till the screw driver gets pushed out all the way, now check the rotor. Is it pointing at the correct lead ?

Read the tinware and make sure you do actually have the right cylinder no to the correct order.

When I built my last engine I put it in, bolted on the webbers, and started her up, ran like a dog, I pulled it apart and put it back to geather again and again. Rang Wes up and asked him for any ideas, pulled the webbers apart again, checked everthing over and over and over. Swore a lot had others look at it they swore as well.

Then another less mechanical mate came over and I was bitching and he looks at the engine and goes " man these plug leads look wrong" WTF I said no way, changed em around to show him whqat a dick he was, turned the key and the baby came to life.... I think we know who the dick was on that day.

Morale to the story, those plug leads are tricky little buggers.
:bounce:bounce:bounce

Brad, No1 can be at TDC with the exhaust valve wide open! That's why you need the rocker covers off to see what the valves are doing! Also, use a pencil down the plug hole- less chance of damage.

Its got to be ignition...

1 check the dist drive for correct position... get # 1 on TDC and check position of drive gear. Theres a pic in most of the manuals which shows the odffset in the correct position.

If this aint right nothing else will be right.

Have you adjusted the tappets correct do they have 0.006" clearence on each cylinderat TDC.

Thanks for all the replies:

:beer

GORDON: I havent checked the compression or thetiming of the valves to the bang timing yet, thats the next thing to check i think.

DOUG SWEETMAN: the notch on th dizzy body is at about 4-5 o'clock.. I checked the leads and got someone else to cross check them too... they're all correctly installed. Plenny of Optimax in the tank (like 3/4 full) and the fuel pump is pissing like it's just been to the pub. So all good on the fuel feed front.

WES: Could be the dizzy clamp... thats the one you loosen up to adjust the timing yeh? I'll have a look and push the dizzy donw onto the black just to make sure.... I'll keep you posted. The dizzy cap is a tiny bit loose, but not up and down loose. Only a tiny bit about 1-2mm circular freeplay)

BRAD: man, i wish you were right. I got brand 'spank-your-ass-red' new leads - 8mm high temp silicon Top Gun ones... tested the resistance and they were all about 8K-9K ohms. I think i have a large 40HP dizzy. The vac advance is working( i can hear the diaphragm do its thing from the air it moves to and from the carby when i moe it by hand). I did theat screwdriver test already and that was ok. It's firing when it should be. Though i think a valve test will 100% sort that out. Dude, I'm saying WTF and dreaming WTF everyday i look at my idle bug under my verandah!

GEODON: i was thinking the same thing! I'll check it out this weekend. I used a screwdriver anyways... heh There was a noticable scraping of carbon on the end of the piston when i removed the screwdriver... so maybe i'm running a bit rich.. But the plugs have been cleaned (they were a bit black).

DAVE: gonna do that this weekend... i havent toughed the tappets yet. They seemed to be ok when she was running last... apart from that big ass flat spot which suddenly appeared AFTER work. (getting there in the cold cold morning was fine with the choke etc)

:cry
The good man Dean aka Grey57 may be coming around for a head sctraching session this weekend if another mate cant help me sort it out before Saturday. Please pray to all your respective Gods and superbeings for grace and patience and the knowledge to know when to walk away before you drive a sledgehammer into the enginebay....

:jesus

Tofu, I'll bring some copper cored spark plugs leads over with me. I am not a big fan of the silicon ones on a air cooled motor.
Dont ask me why , but I have had trouble with this type of lead before on VW motors. Never had a prob with the copper wire type.

From memory it is possible to get the dizzy rotor on a 40hp motor 180 degrees out. Later engines had the slot offset. But as long as the firing order was 180 degrees out too, it should start. Just have the No3 cylinder retard on the wrong. cylinder.

here is my suggestion...as I have had similar problems with engines I built and then left sitting for several months. If you know you are getting spark put a pencil down the barrel of the carby and get a 600ml plastic bottel with some two stroke and pour it down as someone cranks her over. If it kicks then dies its probably fuel related, if it runs I rock good luck.

??

the pencil down the throat guides the two-stroke oil down the throat of the carby yeh?

What does this do?

Well, everything I have thought has been mentioned by someone else...
old fuel can cause problems... not sure how long the fuel has been standing...
You shouldn't have any free play with your distributor body.. it should be tightened up with the clamp until it Can't move... Have You looked down the carby to see if there is fuel spraying into the inlet manifold... certainly a hard one...
Basically,if You have Spark-Fuel-timing OK-leads correct- it should go... Have You tried another coil... coils can short out and have a lower output than normal..
Does this engine have an electromagnetic idle valve?? Is it opening up with the ignition on??
Is the coil polarity correct?? coils will work (sort of) if wired up incorrectly..
cheers
Lee

I'm hoping i'm just a goose and hav forgotten something...

The fuel is about a month old... but i've poured newish/er fuel from the lawn mower can down the carb to no effect. The actual dizzy body has no play when the clamp is tightened, i just have to check that i haven't lifted it a bit (doubt it) But i dont have many options left, so WTF, I'll jsut check it. The coil is a goer... i tested it out.

An electromagnetic idle valve? WTF? Its a 28PCI... i think it was off the original 36HP engine, so it's still got a manual choke... and yes, it gets wet when i gas it up on my attemps to start it... quite sure the soil is wired up correctly... its too cold outside right now, so which pole goes to the dizzy body? Just so i can check it without looking through the manual (lazy)...

Tofu, I have found the lure of a new print of "The Good the Bad & the Ugly" & the chance to hear Ennio Morricone's best score on the fabled Astor sound system too much & I'm going to Melb on Friday pm. If that suits, I can have a sticky beak. U2U m.

the coil should be marked + positive to Power, and -- negative to the points/ condenser... It sure sounds like a spark problem or all the valves are closed!!
I think You said You checked the Coil lead & it was OK... make sure ALL the spark plug & coil leads are pushed firmly into the dist cap... and that the copper connections aren't corroded... it would be unusual for all them to be corroded !!
but if the Large 8mm (i think you said)spark plug leads are Not pushed into the distributor cap far enough, there will we No spark at the leads.... simple but it happens all the time...
best of luck
Lee

Lots of turning the engine over without starting can also flood the engine. You then either have to wait for the fuel to evaporate or sloooowly put the accelerator flat to the floor so as not to work the accelerator pump, then try turning it over again. If you don't do this you may fix the original problem but not be able to start because of the flooding!

yeh, I checked the leads, 68AutoBug, and since they were brand spanking new, they were a little too big to fit into the dizzy connections. So i bent them in a bit and i could still hear the grinding of the leads pressing on the brass contacts of the dizzy. So i'm pretty sure its touching ok. but'll triple check just to mark tripple sure tomoro. I'll have a crack at looking are the valves too so make sure they are in the correct position when #1 is firing.

MNS Kombi: I tried to flood the engine, but wheni did and pulle dout a plug to check if it was wet, It was dry as a bone... could smell the fuel from the plug hole though....do the plugs have to get wet to be considered flooded?


Cheers guys, wish me luck tomoro and maybe saturday!

God this is exciting!!
I wonder whats wrong with it?

I have had little to do with the VW motors, It either goes or it doesn't with mine and so far they both just go and go.
But I have just read this post from the begginning and although I may have missed it I havent seen a conformation of compression,
If you have fuel, spark, correct ignition timing, correct lead order, lets dig deeper into possible scenarios, Compression is a possible problem,I am thinking perhaps, is it possible that the Valve timing has changed, and so the valves are opening at the wrong times, perhaps a striped timing gear, Are they metal or fibreglass like a holden six has?
If, as you say, the motor showed no sign of even wanting to start then whatever the problem is, then its likely to be affecting all the cylinders at the same time, so its unlikely to be a poor lead conection or plug as its unlikely to be affecting all the leads and all the plugs at the same time,
So if there is spark, we can assume that the process has made it past the point where it can affect all the cylinders so perhaps we can rule out the spark presence,

this leaves only three more possibilities I think, exhaust,Fuel and Compresion.

EXHAUST.
Well its not likely to be a blocked exhaust without sabotage, and unlikely to stop it all from happening anyway.

FUEL, You say there is fuel, and you see it when you work the accelerator pump.
So unless you have a child that graciously filled your tank with the garden hose and so what you think is fuel is really water
then we can rule out fuel.

COMPRESSION
Although valve timing is usually set it and forget it, there is a slight possibility that something has gone wrong, Perhaps a stripped timing gear, or a bolt has come adrift keeping it all in check.

Perhaps it proves to be something else but this is the logic train I'd be catching if this were my car. as most problems disscussed so far would leave the engine at least attempting to start.
I'm not sure where you live but I would bet its too far for me to come have a look.

If all else fails, join RACQ,NRMA or RACV etc and make them earn their money, however I have met Mechanics from the RACQ that didnt have a clue {mainly because I was driving a rotary engined car}

Hope you have some success, Tony

Yes, when an engine is flooded, normally ALL the plugs should be wet with Fuel...
and the start a flooded engine, You hold the accelorator on the floor while turning the engine over.
It looks maybe its not getting enough fuel.. to check this... pour some fuel down
the throat of the carby... then if You have spark and compression it should fire up... until the fuel runs out... the needle & seat in the carby may be jammed closed...
Looking down inside the carby throat, when the throttle is opened, You should be able to see fuel squirting down inside the throat....
Lee

68AutoBug: You want to talk about flodded engines?! Youshould've sent he effort Grey57 and I put into my engine! It was gushing fuel out of the exhaust pipes! Now think about it- how high the valves are from the bottom of the cylinders and then how high the pee shooters are from the bottom of the muffler...yup... thats a lot of gas....

:vader

aaaaaaaaanyways, thanks to Dean, (and the majority of a days trouble shooting and 3 carbies later and a flat Pulsar SSS battery, WE GOT BELLE STARTED! :bounce Oh how good she sounded! And the cause?


i think i put the leads on the wrong way...




OMG you're all probably thinking, what a wanka.. but ask Dean, there was a myriad of other problems that didnt allow it to start even after we sorted out the firing order... We ended up changing the leads to old school copper cored ones (thanks for those again Dean!), re-did the timing and even adjusted some tappets. So apart form the WRONG FIRING ORDER (i had it looked at at least 5 times! i'm so ashamed!) we dont know exactly what was causing it not to start.. the fact that the compression was pretty shite, PROBABLY didnt didnt help things much.

After we left Belle idling over lunch, she was still farting and gasping when i tried to rev her. The warming manifold appers to be very partialy blocked and not heating up the intake throat under the carby. I drove her around for about 20 mins and the symptoms started to go away! After another 10'ish minutes driving in the rain (and nearly having a stoopid Bluebird locking it up and nearly taking off my fornt end) Belle was quite well mannered. So i'm thinking here that its icing of the manifold thats making the farting and coughing and general bitching. Perhap's its time to go and get one of those manifold heater blankets very very soon.. AND MAYBE AN ENGIE WITH BETTER COMPRESSION AND 12V!:alien

I tried again to start her this morning and she nearly started, but she didnt... and i had lent my jumper leads out to someone else... so I'll try again after work and i might still have to push start her after all...

BIIIIIG shout out to Dean... thanks fo much for your trek across sunny Melbourne to help a fellow oval in distress, and i think i owe you a slab... as long as you dont hog it all......


oval TOFU aka Belle

:beer

Glad to hear it was not too big a drama,
If the motor was really full of fuel, you might want to change your oil as it may have taken in fuel, Who knows?

Cheers Tony

Any time mate. Dont forget to set up and wire up that auto choke. Probably make it easier to start as it like a bit of fuel to get going. Glad to hear it got better after a bit of use.
Thats good advice about the oil change too. Give it a good service, valves, points timing.

Think part of the problem was a mismatched carby and distrutor. Carb was manual choke 28 and a vacuum advance only distrubutor. The point were the vacuum is taken off was pulling max advance at idle.
Changed to a 28 with electric choke, (different vac take off point) and timing was then behaving normally.

She did finally start today! I forgot how she likes to be started... gas, no gas, little bit of gas, gas first then close throttle, gas then open throttle... so fussy.... (its one press of the gas pedal (roller) and then close throttle...

she didnt seem to be flat spotting much, but i'll find out agian tomoro when i drive her... i'll try to drive her or at least run her a bit at least every second day,,, i dont think this engine likes to be left alone for too long....

compression is at nearly half as what one of my manuals say (they alwasy have varied and sometimes conflicting information)

very good point about the contaminated oil too... i should change it asap...

Thanks again to all that offered thier help:beer:beer:beer:party

I might be on the look out for a new engine on the holidays.....