33Ti 1500 - Timing

[dazjaz]

Am restoring my 86 alfa. Have a problem with timing after having heads done up and buttons set by mechanic. Cannot get the timing right. Have lined up 3 marks, two on cam and T on flywheel but the thing keeps blowing fuel back out the carbie throats. Happens on all 4 cylinders. Has me beat. I would assume that the timing was out but have checked the marks time and again and have even watched the cams while turning the motor by hand. The motor nearly starts until the fuel runs out. Anybody have a suggestion. Am about to set fire to it!

[STRADALE]

is 180 degrees out

[STRADALE]

ignition might be 180 out?

[Sheldon McIntosh]

Yes I concur with Sportiva#22.  I did the same thing when I changed my cam belts, because I'm hopeless and moved the flywheel, had exactly the same symptoms.  Swapped the leads over and she fired first time.  Hmm, must remember to swap them back next time I do the belts, or else let the next owner know...

[dazjaz]

How do I fix the problem. 180 out means that the timing marks on the cam should be set for no.2 not number 1. Is that right

[Frank Musco]

Good job Sheldon, your spot on, swap the leads because the engine has been turned without the dizzy in it, so its 180 out.

The cambelt/valve timing is right, so don't touch it.

If you don't like the idea of swapping the leads, removed the dizzy and rotate the motor back to where it should be.

[dazjaz]

can it be out by 90 and how do I know where the engine should be

[Sheldon McIntosh]

As long as the cams are lined up correctly and the flywheel T is lined up, it's either at 0 or 180.  If it's not firing, swap leads (from memory swap from one bank to the other, but also from memory it was obvious which ones to swap.  I worked it out, so an educated monkey probably could as well). 

[dazjaz]

The cam timing marks are a line at the back of the cam and cam housing notchon the left of centre. Is this correct. To my logic, piston is on the up stroke when intake is open for fuel to be pushed out the throat so is 180 out. A piston rises twice in one cycle, the first time to compress the fuel prior to ignition and second to exhaust. So regardless on which stroke the cam is set to, so long as it is set to TDC should make no difference. Right? Can't fathom that the dizzy would have anything to do with it. To me, the dizzy supplies the spark. So long as the stroke is at TDC and the cam is set to TDC and the Dizzy set to fire No1 it should work but it doesn't. Will try changing dizzy position tomorrow. Changing leads stopped fuel spraying out the throats but wouldn't start.   

[Frank Musco]

Thats correct.

Number 1 piston at TDC,
Both cams with their marks lined up exactly with the notch on the back of the cam boxes
And the dizzy at Number 1.

Its an Alfa boxer motor, Tomorrow morning it will go first turn of the key.

Hows the Battery, because if its turning slowly the motor wont start. They like a good battery.
Good luck

[dazjaz]

thanks all who helped

[Sheldon McIntosh]

Did it start?

[dazjaz]

No. Checked slot on dizzy - correct. My dizzy points west on no.1. at TDC. Still pushing fuel out throats. Close to starting still. tried swapping plugs did nothing. From the mark on dizzy for no.1, advanced dizzy got slightly better but still wouldn't run. At TDC both no1 and exhaust no3 valves closed and no3 just opening. No2 exhaust just closing and no4 exhaust just opening. Alfa 33 built 1987. Have tree marks on flywheel after two big holes. Using T as TDC - correct. Could the dizzy be out say one tooth. Does the slotted piece move up and has changed position similiar to that on other cars. Could this be the problem.   

[dazjaz]

The problem is that if I rotate the crank 180 and line up the cams my dizzy will be out 180. The only thing I can think of is that when I lifted the Dizzy out I also moved the slotted bit thus throwing the timing of the dizzy out 1 tooth or so. It's the only thing I can think of. If I change the cams 180 to the crank, it will make no difference - is that right- as each rotation of the crank is the same.

[dazjaz]

I have been using a very faint T as TDC but have just found what looks like a pin sticking up about 3 mm just past the T. Is that TDC and if not, what is it.