04-10-2003, 01:45 PM | #1 |
Registered User
Join Date: Jan 2002
Location: WATAUGA,TX
Posts: 675
|
7 Cylinders
On the way to work this morning I got on the freeway and got my Blazer up to 65 an all of the sudden it starts acting like its only running on 7 cyl. No power. Eased up on the gas and the problem seemed to go away. Its probably not the fuel pump as I just replaced it. I thinking probably it the mechanical advance on my HEI distributor. Broken or weak springs. I have one of those recurve kits that I thought I might try. Which spring should I use. It is a stock 307. Ad what shoud the advance be at that speed. Any help ?
__________________
72 2wd 307/AT/AC/TILT WHEEL 78 JIMMY HIGH SIERRA |
04-10-2003, 01:53 PM | #2 |
Registered User
Join Date: Dec 2002
Location: Canada
Posts: 695
|
Hey, you still have one more cylinder than some of us.
__________________
1968 Chevy - 292 with a powerglide |
04-10-2003, 02:05 PM | #3 |
Recovering Truck Driver
Join Date: Mar 2002
Location: Orleans, NE USA
Posts: 1,883
|
How's the fuel filter, they will cause a miss and power loss.
__________________
67 K-20 350, SM465, Eaton rear, 4.56 no spin option 00 Dodge 2500 4x4, 24V cummins, 5 speed Chad South Central Nebraska |
04-10-2003, 02:22 PM | #4 |
Registered User
Join Date: Mar 2003
Location: Bremerton, WA
Posts: 1,839
|
If you hadn't just replaced your fuel pump, I would have suspected a ruptured diaphram. Does your carb have an integral pump and filter?
__________________
Silence is golden, duct tape is silver. - Scott |
04-10-2003, 02:24 PM | #5 |
Senior Member
Join Date: Jan 2000
Location: Cincinnati, Ohio
Posts: 1,492
|
I have a Blazer with a seven cylinder, but that pesky broken rod caused it.....lol
|
04-10-2003, 03:25 PM | #6 |
Registered User
Join Date: Jan 2002
Location: WATAUGA,TX
Posts: 675
|
Its an Edelbrock carb and I did replace my inline filter but I forgot about the one in the carb. Ill replace that one as soon as I get home.
__________________
72 2wd 307/AT/AC/TILT WHEEL 78 JIMMY HIGH SIERRA |
04-10-2003, 04:15 PM | #7 |
Registered User
Join Date: Oct 2002
Location: reno, nv
Posts: 50
|
My monte did that until I found out it was the ignition control module starting to go out.
|
04-11-2003, 01:25 AM | #8 |
Senior Member
Join Date: Feb 2003
Location: WIS
Posts: 1,752
|
7 cyl
Check for an intake leak or a fried plug wire laying on an exhaust manifold.
|
04-11-2003, 06:43 AM | #9 |
Senior Member
Join Date: Apr 2000
Location: Delta,Pa
Posts: 14,950
|
check the sparkplugs pull em all out and make sure they still have the electrodes in em. i had that happen once wasnt any fun.
__________________
Owner of North Point Car Care in Dundalk Md. We specialize in custom exhaust on both modern and classic vehicles. We are a full service auto shop from classics to modern vehicles. Feel free to contact me with questions. I will give a 10% discount to any board member. |
04-11-2003, 07:26 AM | #10 |
Registered User
Join Date: Feb 2000
Location: Center City, MN, USA
Posts: 3,253
|
After you do all of the above easy checks and if you still have the problem, do a compression test.
I had the same symptoms and it took a valve job to correct it. #4 and #8 both had valves that were bad. If your compression tests shows a bad hole squirt some motor oil in that hole. If it gets better it is probably the rings in that cylinder. If not... time for a valve job.
__________________
'70 cab, '71 chassis, 383, TH350, NP205. '71 Malibu convertible '72 Malibu hard top Center City, MN |
04-11-2003, 08:46 AM | #11 |
Registered User
Join Date: Jan 2002
Location: WATAUGA,TX
Posts: 675
|
Thanks guys, Its got 185,000 miles on it so it could be valves who knows. That will be next if all else fails.
__________________
72 2wd 307/AT/AC/TILT WHEEL 78 JIMMY HIGH SIERRA |
Bookmarks |
|
|