bogging
Thread Starter
Burning Brakes
Joined: Feb 2006
Posts: 841
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From: High Desert California
bogging
What can be the cause for a 1975 stored for 24 years to bog down? We changed all the fluids including taking the tank down, new spark plugs and wires, rebuilt the carb, and installed new fuel pump.
She still bogs at 30 - 40mph. Could it be the emission stuff? Car was running before storage with no known problems.
She still bogs at 30 - 40mph. Could it be the emission stuff? Car was running before storage with no known problems.
Drifting
Joined: Apr 2006
Posts: 1,911
Likes: 2
From: gold coast queensland
24 years !!! wow.someone has a good memory to remeber it running fine back then 
this could be a wild one..fuel filter, distrubutor weights ( timing) , vacum.....even though you rebuilt carb it might still be something amiss in there. i would prob try to burrow another carb from a friend of any type that would fit your motor and that way you can at least rule the big one out. does it pick up power again after 40 or stay flat from 30-40 onwards?
this could be a wild one..fuel filter, distrubutor weights ( timing) , vacum.....even though you rebuilt carb it might still be something amiss in there. i would prob try to burrow another carb from a friend of any type that would fit your motor and that way you can at least rule the big one out. does it pick up power again after 40 or stay flat from 30-40 onwards?
Last edited by gingerbreadman1977; Aug 3, 2009 at 07:42 AM.
Melting Slicks
Joined: Mar 2006
Posts: 2,465
Likes: 0
From: Orange Park Fl
I'd check the distributor first since you don't mention servicing it, but as said before, it could be a number of things. Could you be a little more specific in describing the problem?
God bless, Sensei
God bless, Sensei
Thread Starter
Burning Brakes
Joined: Feb 2006
Posts: 841
Likes: 0
From: High Desert California
She starts out fine and you can rev it all you want with no problem at all. Does she bog at 30mph or WOT? Yes and no, from a stand point, I can take off and even peel out but once she hits 30 - 40 she starts bog and just bucks like a wild bronco and I have to release the gas. If you cruise and let her accelerate slowly, she'll hit 60 with no problem but can't even go up a slight hill and start to bog again.
Thread Starter
Burning Brakes
Joined: Feb 2006
Posts: 841
Likes: 0
From: High Desert California
24 years !!! wow.someone has a good memory to remeber it running fine back then this could be a wild one..fuel filter, distrubutor weights ( timing) , vacum.....even though you rebuilt carb it might still be something amiss in there. i would prob try to burrow another carb from a friend of any type that would fit your motor and that way you can at least rule the big one out. does it pick up power again after 40 or stay flat from 30-40 onwards?
this could be a wild one..fuel filter, distrubutor weights ( timing) , vacum.....even though you rebuilt carb it might still be something amiss in there. i would prob try to burrow another carb from a friend of any type that would fit your motor and that way you can at least rule the big one out. does it pick up power again after 40 or stay flat from 30-40 onwards?It's really puzzling us. Something I forgot to mention, we did take the carb out of the 81 and ran it while the other one was being rebuilt.
Drifting
Joined: Apr 2006
Posts: 1,911
Likes: 2
From: gold coast queensland
im assuming your 81 carb is not the standard electronically controlled rochy then otherwise it would revert back to full rich settings without computer imput. what carb is it and how did it go?
Burning Brakes
Joined: May 2009
Posts: 1,232
Likes: 6
From: Tucson AZ
St. Jude Donor '12
Even if you replaced the filter, 25 year old gas in the tank is like varnish and could have fouled the fuel system again.
What a blast that must have been to get it running!
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Thread Starter
Burning Brakes
Joined: Feb 2006
Posts: 841
Likes: 0
From: High Desert California
Thread Starter
Burning Brakes
Joined: Feb 2006
Posts: 841
Likes: 0
From: High Desert California
Did you also replace the fuel filter? What shape are the fuel lines in? How is your fuel pressure? Its sounds like the carb is starving.
Even if you replaced the filter, 25 year old gas in the tank is like varnish and could have fouled the fuel system again.
What a blast that must have been to get it running!
Even if you replaced the filter, 25 year old gas in the tank is like varnish and could have fouled the fuel system again.
What a blast that must have been to get it running!
We initially put 5 gal of premium and 2 gallons of racing fuel just to make sure that whatever remaining fuel in the line gets neutralized.
Drifting
Joined: Apr 2006
Posts: 1,911
Likes: 2
From: gold coast queensland
so both carbs did exactly the same thing?
could be a blocked cat but that normally restricts power all the way through the rev range and eventually stops it all together.might be worth taking off the back half of your exhaust and going for a noisy run and while your at it you can check your heat riser flap is not stuck shut.
could be a blocked cat but that normally restricts power all the way through the rev range and eventually stops it all together.might be worth taking off the back half of your exhaust and going for a noisy run and while your at it you can check your heat riser flap is not stuck shut.
Last edited by gingerbreadman1977; Aug 3, 2009 at 09:43 PM.
Thread Starter
Burning Brakes
Joined: Feb 2006
Posts: 841
Likes: 0
From: High Desert California
so both carbs did exactly the same thing?
could be a blocked cat but that normally restricts power all the way through the rev range and eventually stops it all together.might be worth taking off the back half of your exhaust and going for a noisy run and while your at it you can check your heat riser flap is not stuck shut.
could be a blocked cat but that normally restricts power all the way through the rev range and eventually stops it all together.might be worth taking off the back half of your exhaust and going for a noisy run and while your at it you can check your heat riser flap is not stuck shut.
Well, it did start as one and mostly retired military but now young-blood are moving in.
Thread Starter
Burning Brakes
Joined: Feb 2006
Posts: 841
Likes: 0
From: High Desert California
Took her out again and found out that as long as you cruise her down the road, she'll pick up with no problem but soon as you gas her up, then she'll bog down ridiculously.
Thread Starter
Burning Brakes
Joined: Feb 2006
Posts: 841
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From: High Desert California
Burning Brakes
Joined: May 2009
Posts: 1,232
Likes: 6
From: Tucson AZ
St. Jude Donor '12
Drifting
Joined: Apr 2006
Posts: 1,911
Likes: 2
From: gold coast queensland
looks like you will have to check what sensei been saying all along- ignition and what robb said as well - not just the line from carb to pump but is line from tank to pump as well , it might be crushed or something.