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Jace

Help a n00b get his car running right?

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Hi everyone.

My 2002 is having issues with the tune. i'll list the details of the car and then explain the symptoms.

- refreshed M10 (rebuilt using original valves/cams/pistons/rods etc)

- rebuilt and re-jetted Weber 32/36

- new spark leads

- new rotor button

- new distributor cap

- new fuel and air filters etc

The car ran pretty good for a while, but wasn't good enough so i set about replacing the ignition parts listed and also did a valve-clearance adjustment (All valve's are adjusted to .006")

I'm not able to get it timed correctly. If i set the timing to where the small BB on the ring gear of the flex plate is lined up with the hole on the bellhousing near the starter, the car will idle alright but once under load/above 2k rpm will splutter and choke and bog down.

At this timing point the front timing mark will be a good few cm's off, with the front timing mark aligned with the spike on the block then the ignition timing is so far off that the car will not idle and struggle to start.

The idle is pulsing, like a subtle 'hunting' at about 1200-1500 rpm. Idles rougher set at a lower rpm's.

I timed as per the manual (blocking off vacuum advance line etc) but still can't get it right. I feel like i should be able to get it 'close enough' to a point that it is driveable, but i don't seem to be able to.

I'll continue to fiddle with it, but i'm already at the regrettable point of wanting to pay somebody to fix it. :(

TIA for any help you could provide.

- Jace

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Did you set the timing at 1500 rpm with the vacuum advance line disconnected?

After re reading your post, it sounds like you did.

What does the ball look like in the window? Steady? Jumping about?

Have you checked for vacuum leaks around the intake?

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do not 'time' using the front pully.

only time with the " BALL" mark seen in the rear inspection

hole at 1500 rpm - no vacuun to the distributor while

checking

still have points ? need point gap set first before timing

is set! gap at 0.016" or DWELL setting 59 ...65 degees

dwell is the most accurate way producing best power

and fuel economy

no points - now have electronic ? timing light method

still the same at rear inspection hole @ 1500 rpm

and no vacuum to distributor

and,

same symptoms you describe are caused by poor carburetor

rebuilding. the jets and locations, secondary functioning

correctly

very simple once you really understand the function of

every system and the effects each has on running

Basic Internal Combustion Engine 101

read :

library books

BMW Owner's hand book

BMW Repair Manual

also - need to see proof of good COMPRESSION test readings

before any of the above.

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Start at the beginning of assembly, mechanical then ignition. Confirm crank to cam timing first at #1 TDC compression stroke, open up your valve lash a bit. confirm firing order 1-3-4-2. Confirm carburator jet passageways are clear. Confirm correct float level. Check that all extra intake manifold vacuum ports are sealed. check vacuum advance diaphram works and moves advance plate.

as well as other suggestions in response to post.

Daron

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Question: When setting timing, pulling the vacuum advance from the distributer, should you block the now vacuum leak from the pipe you just pulled or maybe it doesn't matter?

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Question: When setting timing, pulling the vacuum advance from the distributer, should you block the now vacuum leak from the pipe you just pulled or maybe it doesn't matter?

yes,yes.

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That is what golf tees are really for, not that stupid game with the little white ball.

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Did you set the timing at 1500 rpm with the vacuum advance line disconnected?

After re reading your post, it sounds like you did.

What does the ball look like in the window? Steady? Jumping about?

Have you checked for vacuum leaks around the intake?

yep, i blocked the vac line with a drillbit

ive searched and searched for vacuum leaks but ive found none.

the ball on the flex plate wobbles erattically and barely stays in the window. even if i set the timing so its in the window for the majority of its wobbles, the car still wont drive correctly.

points gap is one of the few things i havent checked. ill check that tonight. (its 12.45pm atm)

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