Air leak, carbs or dizzy problems

[maximillion]

HI,

Got some running issues at the mo, classic dying on tick over, popping and farting and very lumpy. Trying to narrow it down, the symptoms came on over a period of time but then got much worse quite quickly.

Its a 2l air cooled cj engine

I cant find any air leaks on the vac lines and sprayed WD40 around with no effect on engine tone, the elbow and t piece were a little loose but i have jubilee clipped them up.
Its got electronic ignition with a dual vacuum dizzy, the one with two vac lines, the top one is pulling a decent vacuum but the bottom one isn't, how should these operate?
I have timed it to about 7º ATDC and revs to about 30º BTDC, but if i disconnect the vac lines the timing stays about the same but the engine runs a bit worse.
I have played with the timing but not been able to get it running any better.
Smells of fuel, almost feels a bit flooded when i'm trying to start and takes a few revs to stabilise it.

I am just a DIY mechanic and not sure where to go from here, any thoughts appreciated or does anyone know a good Aircooled mechanic near Maidenhead, berkshire?

This may or may not help: https://www.youtube.com/watch?v=8aiYVjE ... e=youtu.be" onclick="window.open(this.href);return false;

cheers

[bigherb]

Take some pictures of the engine especially the vac pipe layout. It doesn't look right.

[maximillion]

A few photos of the vac hoses etc

IMG_1298 by antnoyce72, on Flickr

IMG_1299 by antnoyce72, on Flickr

IMG_1300 by antnoyce72, on Flickr

[bigherb]

Ok The vac lines appear to be connected correctly just badly done there is a potential for leaks.
Buy some 3mm silicone hose and do it properly comes in different pretty colours if you like the bling.
http://www.ebay.co.uk/itm/3M-Vacuum-Hos ... 5oR5sAatVw" onclick="window.open(this.href);return false;

The fuel line T piece is too high, the fuel line should be below the top of the carburetor to stop syhoning.

Which is the top vac line you checked for vacuum?

[maximillion]

Thanks, your right - it is a mess!

Could the fuel lines cause problems like this? There is a fair bit of excess fuel line behind the tin too. Its always had intermittent power loss and hesitation so would imagine thats not helping.

Looking at it now, i think i removed the pipes from the t piece, and had a vac off the top left line, but not off the bottom one from the dizzy, i didn't actually remove the one from the top of the dizzy looking at it now?

[bigherb]

The fuel line should not cause those symptons but a problem after the engine is switched off. But it is all these little problems that should be eliminated.

Vac pipe 1 should have a strong vac signal at idle decreasing as the throttle is opened.
Vac pipe 2 should have no vac signal at idle increases when the throttle is opened.
First check the the diaphrams in the vac units are not split you should not be able to suck any air through them.

[maximillion]

Thanks, just ordered pipe and the servo elbows etc so will change all of that and see how it goes from there.

[maximillion]

So... had a busy evening.

Re-Adjusted valve clearances, number one was really tight, almost no slack. Changed all vac pipes in the engine bay and renewed elbows / t pieces - a few cracked pipes but no major holes or splits. Cleaned air box, new filter. Checked the advance and retard by sucking/blowing on pipes, they seam to be working and not leaking. With engine on, the retard has good pressure that the advance has pressure but maybe not as much.

Ran much better but still wont idle, got it to just tick over by bottoming out the idle screw (only half a turn)... smells of fuel, the left carb is popping and exhaust backfiring... advanced and retarded the timing to no massive effect to the better.

Worst still, went for a quick drive around the block, drove ok ish, but after a couple of mins i could smell burning, it seamed a bit smokey / maybe rubber / oil / wiring? But i cant find any damage to plastic, belts or wires, not something i have had before...

[kevtherev]

So... had a busy evening.

Re-Adjusted valve clearances, number one was really tight, almost no slack.

There are no clearances to adjust unless your engine has non standard cam followers fitted.
Hydraulic cam followers were fitted at the factory

[maximillion]

There are solid ones for some reason

[bigherb]

So... had a busy evening.

Re-Adjusted valve clearances, number one was really tight, almost no slack.

There are no clearances to adjust unless your engine has non standard cam followers fitted.
Hydraulic cam followers were fitted at the factory

Its a 2l air cooled cj engine

CJ was a Bay window engine only the very last engines produced had hydraulic tappets.

So... had a busy evening.
With engine on, the retard has good pressure that the advance has pressure but maybe not as much.

That's correct but it is when you have those vacuums that is important.

Ran much better but still wont idle, got it to just tick over by bottoming out the idle screw (only half a turn)... smells of fuel, the left carb is popping and exhaust backfiring

Check the float valves are not allowing a carb to flood and check the idle solenoids are working.

[maximillion]

Solenoids click and engine slows / dies if i remove the wires

To check the floats i assume i have to strip the carbs down?

Making a bit of a screeching noise from the right hand side too, not sure how clear you can hear it, you can hear it clearer from the front...

Running (Dies if i let go of throttle)
https://youtu.be/yJL2FD8j6yo" onclick="window.open(this.href);return false;

Noise? (air box is off)
https://youtu.be/6G2zEGy3ksQ" onclick="window.open(this.href);return false;

[maximillion]

Bit of progress... sprayed some throttle cleaner into the carbs and tried revving the engine high and blocking the air intakes off and i have got an idle back, its a little slow but seams much happier.

I have read and interesting post that was on another carb thread on 80-90 http://itinerant-air-cooled.com/viewtopic.php?t=7767" onclick="window.open(this.href);return false; and i am going to try this method of adjusting the timing... might be camping in it at the weekend after all, you never know

[maximillion]

Had a lot of progress, rebuilt the carbs, they are back on and setting up at the moment.

Couple of quick questions:

Whats the best way to time it - with vac disconnected at revs to 25-28 BTDC, or with hoses on to 4-5 ATDC, keep reading conflicting ways to do it?

Also, if i pull the retard at tick over the engine slows, i'm sure i read it should speed up? would that indicate a problem with the dizzy or carb set up?

[bigherb]

Whats the best way to time it - with vac disconnected at revs to 25-28 BTDC, or with hoses on to 4-5 ATDC, keep reading conflicting ways to do it?

You should be checking both.

Also, if i pull the retard at tick over the engine slows, i'm sure i read it should speed up?

Yes it should speed up as it advances the timing to around 8 deg without the retard.