Flathead woes

[fourwheeler04073]

Hey guys, I've been dealing with an issue for quite some time that just has me stumped. I have a 218 3spd in my 53 Cambridge. I haven't been able to give it more than 1/2 throttle or it stumbles and breaks down. It will idle perfectly. I have replaced the following:

points, cap, plugs & wires, coil, fuel filter, and just sent the carb out to be completely disassembled, cleaned and rebuilt. Not sure what I'm missing any suggestions would be greatly appreciated.

[Reg Evans]

Have you checked your vacuum advance for leakage ?

[mmcdowel]

I'm wondering if the fuel pump isn't failing as the engine speed increases....or perhaps the line from the tank (or in the tank itself) doesn't have a restriction?

[De55]

Ditto on the fuel pump. Last summer my '51 Desoto was doing the same thing, especially trying to go up a hill.

I did everything else, just as you did but it turned out to be the fuel pump. Changed it and problem gone.

It had me puzzled because it started right up and would idle all day.....just couldn't put a load on it.

[knuckleharley]

Is there any chanc

 

Hey guys, I've been dealing with an issue for quite some time that just has me stumped. I have a 218 3spd in my 53 Cambridge. I haven't been able to give it more than 1/2 throttle or it stumbles and breaks down. It will idle perfectly. I have replaced the following:

points, cap, plugs & wires, coil, fuel filter, and just sent the carb out to be completely disassembled, cleaned and rebuilt. Not sure what I'm missing any suggestions would be greatly appreciated.

Is there any chance you might have a pin hole in a gas line? The only way I really know to test one is to unscrew it from the tank and the fuel pump,and then block the line and put some air pressure on it with something like a Mighty Mac hand pump. If the air pressure drops,you have a leak.

[Plymouthy Adams]

are you certain your tune up parts are for the correct series distributor.  Over the years it could well have been changed to the other model.....verify your distributor parts by tag on the distributor body.

[greg g]

Have you done the fuel flow quantity test suggested in the service manual?  Unless you are sure that the fump is pumping the correct capacity, all other adjustments are pretty much moot.  

 

If you are getting proper flow, what do your plugs look like?  Is your exhaust clear or is black smoke and gas smell in evidence?  What did your compression test reading tell you about the general condition of your engine?  Have you done a vacuum gauge test?

[Don Coatney]

Have you installed the rebuilt carburetor?

[TodFitch]

Lots of good suggestions in the previous posts but I'd like to add one: On some of the newer point sets there is a separate spring that needs to be installed on the contact arm. If missing then the spring action is only from the copper conductor and the car may start and idle but not run at higher RPM.

[Barabbas]

Lots of good suggestions in the previous posts but I'd like to add one: On some of the newer point sets there is a separate spring that needs to be installed on the contact arm. If missing then the spring action is only from the copper conductor and the car may start and idle but not run at higher RPM.

Yep, did exactly this "dumb" thing and it idled and ran fine--until about 45mph and then lost all power

[Merle Coggins]

Yep, did exactly this "dumb" thing and it idled and ran fine--until about 45mph and then lost all power

 

Yup... I did that once too. Could barely get over 40 MPH and the engine would start cutting out.

[Oldguy48]

When you changed out the distributor internals, did you also change the condenser? Not certain if this could be the culprit, but it's easy enough to try swapping it out if you haven't already.

[fourwheeler04073]

Thanks guys, I'll check the spring on the contact arm today. I haven't done a compression test yet. I was thinking it may be fuel pump but wasn't sure how to test it.

[fourwheeler04073]

Don Coatney, I just put the carb back on Monday. 

[TodFitch]

Thanks guys, I'll check the spring on the contact arm today. I haven't done a compression test yet. I was thinking it may be fuel pump but wasn't sure how to test it.

 

Test for fuel pump is in the factory service manual which you should have a copy of.

[Jerry Roberts]

There is a wire in your distributor that moves every time that you use the throttle . The wire is attached to a plate . If the wire is touching metal where it shouldn't , then your engine will cut out when you use the throttle . Lots of times the insulation gets worn off or the wire could be broken inside of the insulation . The wire is made of very fine strands because it has to flex a lot . 

[50 coupe]

Yup... I did that once too. Could barely get over 40 MPH and the engine would start cutting out.

 

Hahaha, me three. At least it was an easy fix!!

[fourwheeler04073]

I don't have a small spring on mine. Should it have come with the points? What's the best brand or place to buy them? I bought mine at NAPA

[Barabbas]

they are not spirol springs but stainless steel looking leaf springs--they are the same basic shape as the copper connector that goes from the pivot point to the coil connection

[Don Coatney]

they are not spirol springs but stainless steel looking leaf springs--they are the same basic shape as the copper connector that goes from the pivot point to the coil connection

As pictured.

 

[fourwheeler04073]

Thanks Don Coatney, I'll check for that when I get home from work.

[Grdpa's 50 Dodge]

Another fuel issue is I had a fuel hose before the pump collapse on the inside.  Or have heard of a clog inside the tank.  The electrical issues talked about above would be a great thing to check also.

[Jerry Roberts]

I don't have a small spring on mine. Should it have come with the points? What's the best brand or place to buy them? I bought mine at NAPA

 Not all points came with the spring that is mentioned . There are different models from different companies . 

[iowa51]

I will throw this out as a possible cause even though it usually causes hard starting.

 

Did you hook the wires up correctly on the coil when you replaced it? With the positive ground I hooked mine up backwards and it ran, but had starting/performance issues until I switched the wires to the correct sides.