8 replies to this topic

[someone2244]

Hi
Im trying to set my ignition timing up and i cant get it anywhere near. the best ive had it do so far is to run for 3-4 seconds then cuts out. ive just rebuilt the engine and fitted a kent 276 cam and set the timing to what they suggested (i think around 106-109 of the top of my head) i was just wondering if this will effect the ignition timing and how i would know where to set it to?
my engine is a mg metro 1275
ive got spark, fuel and compression im using these instructions:

The second topic is ignition timing and obviously extended from that... the firing order. Set the parking brake, place the gearbox in neutral, take the rocker cover off and remove the spark plugs. Turn the engine over by hand IN ITS NORMAL DIRECTION OF ROTATION. Look into the spark plug hole for cylinder #1 (the water pump end of the engine). When the piston is visible near the top of the bore, grab the rocker arms above cylinder #1. If they are "tight" so you cannot move them, turn the engine over one more complete revolution. When #1 piston is at the top, try the rocker arms again. If they are loose (you can wiggle them) then you are at #1 TDC on the firing stroke (where you want to be). Now take the dizzy cap off and look at where the rotor is pointing. Hold the cap over the distributor like it would be mounted. Note which terminal on the cap the rotor is pointing to. Put the spark plug wire for cylinder #1 on that position. Now put the other wires on in the order 1-3-4-2 going COUNTERCLOCKWISE around the cap. Your plug wires are now on in the correct order.

Move on to ignition timing. Now rotate the engine BACKWARDS through about 1/4 revolution. Stop and then SLOWLY turn the engine forward until your timing marks line up with the pointer. Stop when the pointer is aimed at somewhere around 5 to 8 degrees before top dead center. You said you have electronic ignition. What type? Is it factory or aftermarket. You can static time many of the aftermarket types... I don't know about Lucas. If it is aftermarket ignition, connect a test lamp between coil (-) and earth. Loosen the distributor clamp bolts and turn the key to the run position. SLOWLY turn the distributor body CLOCKWISE until the test lamp goes out. Now turn the distributor VERY slowly CLOCKWISE. STOP immediately when the test light just comes on. That is the point at which the coil would fire and make a spark. Tighten the distributor clamp and refit the spark plugs. If you have fuel, you should now be able to start the engine

Many thanks matt

[bmcecosse]

That's not a very fancy cam - just advance the timing till it starts and runs - then move the dizzy back and forth until you get smoothest idle. Then road test and listen for any pinking. If pinking then retard it slightly till you lose the pin king -if no pinking, advance slightly until you DO get pinking - then as above. But I have to say - if it runs for few seconds at the moment -timing isn't the problem - more like fuel supply.......

[Rob-T]

Hi Matt
That procedure does not sound right for ignition timing, I think it should read ANTICLOCKWISE until light goes off then very slowly CLOCKWISE until the light just comes on.
Not 100% sure, but that’s how I’ve always set initial static timing then start it and get a strobe on it.
Rob

[bmcecosse]

And 'strobe' it to what ? Any setting is just a guess - road test (or of course rolling road) is the best way to get it as good as you can for your engine spec. Ideally - it should be optimised all the way up the rev range and the bob weights/springs and advance stop set to best advantage.

Edited by bmcecosse, 22 December 2011 - 09:33 PM.

[Rob-T]

@bmcecosse re ‘’strobe it to what’’

If you read the first paragraph of Matt’s post he can’t start it and has to start somewhere. If he can start it then strobe it to find out what it’s running at, he can then road test it then make adjustments to it using a strobe to check what it is. He will then know what he’s tried rather than guess where it’s at, He can do that until he gets the best he can. OK totally agree, best to get it on a rolling road – but he needs to start it and get it running something like first.

Rob

[dklawson]

Matt's post on static timing "sounds" like he has quoted me from a previous thread.

Rob-T is correct about the direction of rotation and the state of the test lamp. So... if that is copied from one of my old posts I would appreciate a link to it (please Matt) so I can go back and correct the content. I'd hate to see a mistake like that perpetuated.

[someone2244]

hi cheers for the replies
erm checking the fuel supply ive taken the fuel supply to the carb off and fuel spurts out but i havnt done it while cranking yet so i'll do that, how much fuel should i expect out of a standard mechanical pump? also is there a way i can check if the carb is working ok ( its an 1 3/4 su) tho the spark plugs so seem damp and smell of petrol after cranking for a while! cheers


Doug I think it is from one of your posts but i copy n pasted then e-mailed it to myself so i had it on my phone while working so i cant find the orginal post!
ive just looked/ searched on here for while but cant find it ill have a look again when i get some time sorry!

[dklawson]

Oh well. Thanks for letting me know. Just keep in mind that Rob-T is correct concerning what direction to turn the dizzy and what the test lamp should be doing when you turn it.

As a more complete description and correction, that text in edited form was taken (more or less) from a PDF I wrote describing hot to perform static timing. You can read the full document using the link below:
http://home.mindspri...taticTiming.pdf
Sorry for the confusion.

Regarding the fuel delivery, you can simply put the disconnected end of the hose in a catch jar and turn the engine over on the starter to observe the fuel. You asked how much fuel should be delivered. While I'm sure the value is posted in the manuals, I don't think it is going to be "much" or something you will easily measure by yourself. Consider for a moment that your car may average 30 MPG when driving 60 MPH. That is a delivery rate of 2 gallons per hour. That equates to very little flow per second.

A quick test for fuel delivery is to follow Roy's frequent advice to pour a thimble of gas down the carb throat and then attempt to start the engine. If the engine fires, runs for a short time, then dies, you have a fuel delivery problem.

[Neildanks]

I had this problem and found my choke didnt work although the cable was pulling. I kepept trying to start it it would run a few seconds then stop but after keep trying it eventually started enough to run.