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We've dropped another engine into my Mrs 2002 but used an e21 unit so that she can have leccy ignition. The thing is that it will only start and run for a short time before conking out. It seems to start missing and dying as soon as it warms up?

Is it possible that the dizzy might be 180 degrees out causing an ignition fault?

Does this dizzy look right to you guys?

T'other way round on the 318i E30 M10 we just put in mine iirc, as it was being crushed against the bulkhead .. Murran should be able to confirm though as he'll testify, my memory is shocking.

yeah the vac advance bit was the other way round on the m10 out of recks car and the one we have just put in. but even if it is the wrong way round it shouldnt matter as long as the plug leads are the right way round (in relation to the dizzy) ei; no1 plug lead is on no4 and 3 is where 2 should be and visa versa to take into account of the dizzy being 180 out.......
if you time it up on tdc and take the dizzy cap off, if the rotor arm is pointing at no1 on the dizzy cap and the leads are on in the right order.
have you got a timing light?

have you checked the valve clearences? if some are tight, when it warms up you'll be loosing comp. thru the valves not seating 100%.

other than that id presume the carb is causing usual rubbish carb related problems. (i hate carbs!!)

Its got a brand new single choke Weber so am sure that it's ignition related. I'll spin the dizzy 180 and try again. Cheers tho.

The dizzy on my old car was that way round, if you were 180 out it shouldn't work at all. Your timing may be off but 180 out would - so far as I recall - put fuel in the exhaust and light it just as the valves closed.

Starts and runs for a bit sounds like fuel to me - pipes and filter new? what about the pump. Presumably it's on the cylinder head and engine driven, but is it knackered. Then we have electronics - Have you got a spare ignition unit you can swap in, I have one, and Reck also has one spare. If coil and leads work initially it is unlikely to be them, but I did encounter some badly fitting ignition leads a while back which lost their grip on the plugs as they warmed up and caused misfires/conk out.

Is it auto choke or manual? Does choke in/out make a difference. Also what if you disconnect vacuum tubes from dizzy (obviously plug them so as not to cause a leak). Are the vac tubes the right way round as well??

JIm

I thought fuel pump too, so just ordered one off eBay. It might be that soon as carb empties problem starts and current pump can't match demand?

it can be 180 out. so long as the plug leads matched the dizzy position. and its set up timing light wise. these things are totally run off the dizzy, no crank sensor like a 325i lump. so the dizzy can effectivly be in 4 different positions and still run......

have you moved the dizzy at all? mark up its current position and with it running, try moving the dizzy a few degrees either way see it it gets better. if the timing was out a touch when it comes off choke it may struggle to tick over.

do check the valve clearences tho as ive seen what youve described caused by tight valve clearences.

doubt its the fuel pump. mechanical pumps always work, if not the diaphrams split. easy to check just pull the feed pipe off to the carb and crank it over. fuel comes out its working.

Check the dizzy cap, the carbon contact can soemtimes perish out so the spark has to jump, when it heats up it reduces the electron flow reducing the spark's efficiency

Well we span the dizzy 180 degrees and it seems to have solved the running issues. In fact, it's a bit of a peach tbh.