Dodging Speed

[FMSPEED49]

OK, first post, but was refered here for an answer,any help would be apreciated. thanks in advance.

1949 Wayfarer, stock everything, 110lbs compression, new points, new cap/rotor, new condensor, rebuilt carb, valves set, timing set over and over. 3 speed fluid drive. new wiring, 15" 225 tires, vacume advance working well. new fuel pump, new lines, cleaned and vated tank. new plugs. new wires. fluid in coupler changes to tracker oil w/ low foam.

Runs like a champ till 61 mph, then falls off, like its is floating the valves.

First gear 21 mph, second 31 mph, third is 61mph. up hill down hill, she don't care.

Is this just all there is, or do I have somthing wrong, possibly weak valve springs? or am i missing somthing

[bob westphal]

Have you checked your throttle linkage to make sure your getting full throttle? Can you explain 'falls off'? Does it miss, flubb, run smooth but won't go faster?

[277 HEMI]

the fule pump and float setting of carb.

[Normspeed]

If you have a fuel filter, check that it's not clogged. That would include the little strainer in the glass bowl area of the fuel pump.

[FMSPEED49]

Fuel pump is new, the brass screen and sedement bowl are clean, the float is set to the book, and clean, the throttle hit wide open. carb ( standard 1 bbl) been gone thru and rebuilt.plugs are showing a nice light brown.

I'll try to describe the problem a little better, at 61 mph, it almost cuts out like it has a governer, power drop off completely, and pops quite a bit, almost if u will like you pulled the wire off the dizzy, acts just like it has a governer.

at 55 mph, if u punch it, it pulls fine all the way to 61. reminds me of the governer on a new car, when u 95 it cuts the coil, drop out of it and its fine.

its got me stumped, but i guess this IS NOT NORMAL from this motor eh?

[grady hawkins]

You might check your points to see if they are laying down at speed by holding a plug wire off the plug and watching the spark as your RPM increases

[Guest Nile Limbaugh]

Sound like a fuel supply problem to me. You might want to check the fuel pump output, new or not. It might not be up to snuff. Otherwise, how many miles on the engine? Even with a valve grind, if the stems and/or guides are badly worn it will affect the performance.

[FMSPEED49]

bout 74 k, fuel seems ok till then, but it put a gauge on it.

[TodFitch]

Could it be that the points lead is being grounded (or going open) at some as the plate the points mount to is rotated by the vacuum advance?

You could test that pretty easy by putting a hand vacuum pump on the advance unit (blocking the port on the carburetor) and seeing what happens when you apply vacuum.

[Jerry Roberts]

You mentioned that it acts like it has a governer on it . Does it ?

[Bill pilot99]

I had this many years ago on a 49 Plymouth,

We found pin holes in the gas supply line, rusted out.

[greg g]

For the price of a new one, I'd also throw in a new condensor. They can fail and cause all sorts of gremlin like problems. The govenor question is intersting, can you post some pics of your engine? Had an intermittant proble with mine a couple of springs ago. There was a piece of debris in the fuel pump. I have a single chamber pump with no glass bowl. The problem sounded a little like yours, the car woud idle al day, rev with no problem with no load in neutral and drive with out problem till about 45 mph. Drove me nuts, finally I dissasembled the pump and found a piece of debris in the hollow bolt that holds the bottom of the pump on. The bolt as well as holding the bottom pf the pump on also functions to allow fuel to pass through it. there was a piece of debris inside the hollow body of the bolt that was acting like a flapper valve. Under low volume situations it would stay open and allow fuel to pass. As flow increased, it would close with the current, limiting passage causing surging at anything over 45. I also found some rust blocking the internal screen in the fuel pump lower chamber. Even though all the components are new, I would check them again. I had a slant 6 years ago with a partially cloged fule filter that would do the same thing, as long as you wanted to go 50 it would go all day, ask for 55, buck bang stutter, let off the gas slow down and it would runn nice and smooth. One other thing, make sure your spark plug wires are fully seated in the dist cap. You really gotta wanta push them down in.

Did you do the fuel flow test I sugested on the other forum???

[FMSPEED49]

pulled dist, looked good, but figured while its out i might as well get all new parts . waiting on all new replacment parts, be here tommorow, figured if i have it out, its all getting changed, so if that don't help i'll head towards the fuel side, as far as it having a governer, not that ive ever seen, and i rewire the whole car, so i'm thinking, no.

[FMSPEED49]

also, this thing performs flawlessly, has plenty of power ( year and size being considered) right till 61 every time. it'll run right up the biggest hill i can find with 4 people in it, or downhill doesn't seem to matter.

[De Soto Frank]

Sounds like fuel starvation.

Had this problem a LOT with my '48 New Yorker the first year it was back on the road... culprit turned out to be fine rust from the fuel tank kept clogging the fuel filters ( I had added two Fram G-2 inlines).

Other possible causes: perforations in fuel line between tank and pump - might not be bad enough for fuel to drip and puddle, but enough to admit enough air to cause starvation at high speeds; another possibilty is a blocked vent on the fuel tank/ fuel filler cap; could also be a coil in the early stages of failure.

Not sure what rear-end ratio is in a Wayfarer. but 60 MPH is getting near the red-line on the engine, and requires maximum fuel delivery from the tank.

I've had a number of other MoPars ( '60 Windsor, '64 Valiant), and a '72 Chevy truck that all exhibited similar high-speed starvation issues ( loss of power/bucking/popping) that occurred on long pulls/full throttle operation, and nearly always abated when I backed out of the throttle; all due to restrictions in fuel lines/blocked filters, etc.

The Valiant has a mesh strainer on the fuel pick-up tube; it had disintegrated, and the pick-up tube was packed-tight with rust at the right-angle bend after the filter sock.

All of these vehicles ran great around town, but out on the highway and on long hills, when fuel demands were at their highest, there would be problems.

Dropping the fuel tanks and thoroughly cleaning them out solved the issues with the Windsor and Valiant, and also with the New Yorker.

Good luck !

De Soto Frank

[Lou Earle]

If your positive ground make sure your coil is wired correctly- neg side to the ignition and pos to dist. If neg ground then pos to ignition and neg to dist. are u 6 volt? or 12? if 12 be sure yoru coil - if a 6 volt has a reducer in between ignition and coil

[JerseyHarold]

Clogged exhaust!!

[FMSPEED49]

exaust is new, w glass pack, same problem before, so that didn't cause it,

6 volt, coils right.

[Guest P15-D24]

All good suggestions, but the most common cause is either or both of the ignition advances are not working. Check the specs then check with a timing light.

[Don Coatney]

If I understand your problem correctly your engine is not surging at the top speed but simply will not pull anymore. If it were surging I would suspect a fuel delivery problem (plugged fuel line etc) but witn no surging it is possibly the throttle butterfly not opening all the way, a restricted main jet, or an electrical problem.

As has been mentioned check your distributor mechanical advance and make sure both springs are in place and have the correct tension.

With the engine not running and the air cleaner removed have someone press the gas pedal to the floor while you look down the throat of the carburetor with a flashlight. The butterfly valve should open fully. If your car has an electric choke on the carburetor disconnect it and make sure the choke butterfly is in the full open position. Check your carburetor to manifold gasket and make sure it is correct for the application. The gasket should have 4 slots in it as pictured.

[FMSPEED49]

GOT IT!!!!!!!!!!!!!!!!

pulled the dizzy, checked, everything looked ok, pulled it all the way down, cleaned it real good, a few drops of oil here and there, put in new points condenser and a cap, set it, set the timing (same settings as it was)

Old points and cap and condenser were less than 6 months old.

Ran down the hyway pulling a registered 85mph

Getting 25-30 mph first, 25-45 second

Thanks for every ones help, It was either a bad part, or somthing sticking, but its right now. once again thanks

[greg g]

Glad you got her going!!! Don't be a stranger.

[FMSPEED49]

I apreciate all the help guys, and i'll be around more, thanks.