Car bucking on a hill

[MalcolmA]

Hi guys,

Recently my 65 (200ci, pretty much all stock, original dizzy with pertronix, 3-speed manual, Holley 1940) has started bucking on a hill near my house. It used to be fine, but now when I'm on that hill around 45-50mph is starts to buck, where it was previously smooth. It seems pretty violent, the car does not like it. Dropping down to 40 clears it. I'm not pushing her, there's a downhill before the up and I build up speed then, I don't try to floor it to get up the hill.

Any ideas? Thanks in advance!

 

[cr_bobcat]

If it's a load issue, it could be related to the vacuume advance? Is it pinging or trying to stall out?

The other thing could be the float. Higher speed up the hill could shift the float level more.

I'm just throwing ideas out here though. Maybe I'll get lucky and pick one that makes sense

 

[Econoline]

I leaning towards carb/fuel problem

 

[MalcolmA]

Feels like it's trying to stall, but I'm not sure what pinging is.

I've got an autolite 1101 (from a 69) and a dizzy from a '69 that planned to upgrade to eventually. Maybe this is the time.

 

[bubba22349]

I would lean towards the carb too! How long has it been since that carb's been rebuilt? Other things would be the SCV and distributors vacuum canister it may have a blown diafram easy to check and see if it's still holds a vacuum. Yes for sure its a very good idea to swap in the better 1969 distributor and carb it will be quite a difference in performance. Good luck edited

 

[RichCreations]

My friend had a 170/C4 auto, that mostly ran fine, except it would buck/stall if he tried to back up his steep driveway, he replaced carb/fuelpump/dizzy, no change. I looked at it for him, and realized it had almost no compression...

 

[chad]

Where do U live? I'm not getting an image of what "a hill" is 4 U.
Visually ck fuel filter 1st as cheep easy beginning diagnosis…

motor mounts OK? (ie isolate the Tq Converter frm the equation).
(They shame me with: "Chad, your thinkin is too outta the box!")
:nono:

 

[wsa111]

Run a fuel pressure & volume test.
Ohm all your plug wires.
Check for carbon arcs in distributor cap.
Install a new set of spark plugs.??????
Coil output.

 

[MalcolmA]

Thanks guys! I should warn you that I'm very green so this is a lot of information, but it's all stuff to investigate.

The carb I believe was rebuilt about 10 years ago, but I'll need to double check the records. I changed the spark plugs about four/five months ago. I live in Southern California, in a suburb up on the hills. If I hit the bottom at 60 and don't give it any gas on the hill then it'll be down to 30 by the top, not sure if that's helpful at all.