 Engine only firing on #4 cylinder |
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| cambum4 |
 Aug 15 2013, 03:23 AM
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#1
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Newbie  Group: Members Posts: 16 Joined: 11-May 11 From: wv Member No.: 13,057 Region Association: None  |
I have a stock 75 with a 2.0 liter engine - converted to webers. I can only get the engine to run on #4 cylinder. Rebuild the engine top end, rebuilt carbs, timing looks correct at 27 degrees. What am I missing?
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| Mblizzard |
Aug 15 2013, 04:18 AM
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#2
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Advanced Member Group: Members Posts: 3,033 Joined: 28-January 13 From: Knoxville Tn Member No.: 15,438 Region Association: South East States |
Not trying to be smart here but how do you know it is only firing the #4 cylinder? If it was running only one one cylinder it would seem difficult to set the timing correctly
I assume you checked for spark at each cylinder? Valves are set correctly? Verified fuel flow through both carbs? Plug wires in correct order? |
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| ChrisFoley |
Aug 15 2013, 08:38 AM
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#3
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I am Tangerine Racing Group: Members Posts: 7,927 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None 
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I've never seen a 914 engine running on only one cylinder.
Two maybe - but one? |
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| r_towle |
Aug 15 2013, 05:35 PM
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#4
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Custom Member Group: Members Posts: 24,577 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States
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1432
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| Rand |
Aug 15 2013, 06:40 PM
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#5
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Cross Member Group: Members Posts: 7,409 Joined: 8-February 05 From: OR Member No.: 3,573 Region Association: None |
They don't run on one. Something strange is afoot at the circle K.
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| cambum4 |
Aug 15 2013, 07:28 PM
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#6
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Newbie Group: Members Posts: 16 Joined: 11-May 11 From: wv Member No.: 13,057 Region Association: None |
Test #1 - remove spark plug wires and engine rpm should change. I remove #1, #2, #3 without affecting RPM - remove #4 with all the others connected - engine stops.
Test #2 - spray carb cleaner over the intake port of the carb - again the engine RPM should change - Only #4 is affected. Firing order correct 1432 Still balancing both carbs. Heads replaced and valves are set correctly cold. Still thinking its something stupid. It will go 55 miles and hour will one cylinder until you hit a hill of course. |
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| r_towle |
Aug 15 2013, 07:51 PM
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#7
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Custom Member Group: Members Posts: 24,577 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States
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Balance is off.
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| ChrisFoley |
Aug 16 2013, 06:19 AM
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#8
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I am Tangerine Racing Group: Members Posts: 7,927 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None
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QUOTE(cambum4 @ Aug 15 2013, 08:28 PM)  Test #1 - remove spark plug wires and engine rpm should change. I remove #1, #2, #3 without affecting RPM - remove #4 with all the others connected - engine stops. Test #2 - spray carb cleaner over the intake port of the carb - again the engine RPM should change - Only #4 is affected. Firing order correct 1432 Still balancing both carbs. Heads replaced and valves are set correctly cold. Still thinking its something stupid. It will go 55 miles and hour will one cylinder until you hit a hill of course. If you pull all three (1,2,3) at once does it continue to run? If you are pulling them one at a time all that proves is the cylinder is not pulling its share of the load. It could still be burning enough fuel to not be a significant burden on the idle. As Rich said, the balance is off. |
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| stugray |
Aug 16 2013, 07:17 AM
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#9
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Advanced Member Group: Members Posts: 3,824 Joined: 17-September 09 From: Longmont, CO Member No.: 10,819 Region Association: None |
I followed this:
http://www.redlineweber.com/html/Tech/idf_...nt_controls.htm Linkages should be disconnected, air bypass screws closed, idle mixture screws out 1 turn, idle adjust in 1/2 turn in after touching arm (both the same). you should read the same flow on all 4 barrels. Stu |
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