1970 Roadrunner won't stay running

[Bobby D.]

Any chance it's still the carburetor? I guess, no, cause it won't idle?

 

[turbine68rt]

here you go

 

[TorRed]

Thank you again!! Oil pump gear was also faced completely the wrong way when on TDC. I haven't installed it right yet.

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Does anyone else think the distributor may be worn out? It's been a long time since I tuned up a car with points, but the bumps on the distributor 'gear' look very rounded off to me which would lead to the points not fully opening. Even with points distributors I always had aftermarket HP units so maybe the 'bumps' were more pronounced on them?

 

[Bobby D.]

Did you buy the car with the engine built the way it is now? If so, hate to tell you this but I would be verifying that the timing chain/gearset were installed correctly.

 

[Don Frelier]

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Oh boy that's not good.

 

[Bobby D.]

Oh boy that's not good.

The Motorcraft oil filter or the timing?

 

[Bobby D.]

This is before and then after I turned it dot to dot. Before at compression #1 (I felt compression with my finger) rotor pointed to #1. After, at dot to dot, (no compression felt) and rotor pointed at #6.

 

[Don Frelier]

The cam was 180 degrees out before and they had moved the plug wires to get it to run.
Now that you have it corrected you'll need to re- index the plug wires.
It should run either way but the cam timing may have been off in your first picture.
Ideally you would degree the cam.
Looks like the timing set is pretty new.

 

[Bobby D.]

So that means my base timing is good? So it still might have a carburetor issue for the reason it won't idle?

 

[Orig69]

I think your right cause I just never liked the idea of the adapter. Is there a good spread bore carb I can buy that'll fit on, what I think is a factory intake? Just to eliminate that possibility.

If you have one of these you can swap it with the adapter.

 

[Bobby D.]

If you have one of these you can swap it with the adapter.

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The Edelbrock linkages are to close to the intake, unfortunately. I'll need a whole new carb. Which it's looking like I'll need one anyways. If my timing is good that really just leaves the carb, or engine. I doubt that but I'm gonna do a compression test though.

 

[Bobby D.]

I have the new crank seal and gasket installed. I need to go buy a harmonic balancer installer. Almost everything will be new, maintenance wise. New spark plugs on the way and I'll go ahead and do a compression test. If that checks out, the issue has to be the carb!! Do those Edelbrocks have an idle circuit?

 

[Bobby D.]

I'm still working on it. I went ahead and ordered some intake gaskets just to seal it up. I haven't done the compression test yet. A buddy at work did lend me his dwell meter and a carb. I also bought a carb for $25 from another coworker.

 

[Geoff 2]

Using an unknown carb to fix an unknown problem is just going to give you more....unknowns.

If you want to try a different carb, try & get one that was working on another engine.....

 

[Bobby D.]

Using an unknown carb to fix an unknown problem is just going to give you more....unknowns.

If you want to try a different carb, try & get one that was working on another engine.....

Both of these carbs were working when taken off. Right now I don't have many options and it's a free option.

 

[Don Frelier]

It's pretty easy to take the top off a Carter and give it a quick clean and blow it out.

 

[Jc cooper]

Check that carb adapter for sealing. Some of those create a huge vacuum leak.
Mike

Easy way to ck for vacuum leak is by either placing hand over the primary portion of carb when running,or slightly close the choke, if vacuum leak, it will speed up ! Good luck

 

[Bobby D.]

It's pretty easy to take the top off a Carter and give it a quick clean and blow it out.

Which of those carbs would be best? I think the thermoquad is a 750 from a 440? The AFB I'm not sure. When I close the choke it wants to die.

 

[Don Frelier]

The AFB is a 625 CFM. Personally I would choose that one.
Take pictures of the linkage on the sides.
Loosen the metering rod covers and remove the rods.
Unscrew the top and carefully take it off.
Remove the idle mixture screws spray or put some cleaner in there and blow it out.
Look up how to check the float setting.
Reassemble.

 

[Geoff 2]

I would also choose the AFB to use for a carb that is to be used for testing.