Fuel Check Valve question 1978SC

[Kemo]

I have a warm start problem with my 78SC. In the morning, it starts fine. If I drive it a while, stop and run into the store for 10min, it still starts ok. But after about an hour after being up to full temp, its a really hard start taking a very very long time to catch. And then, it kinda runs like crap for about 5 min.

After reading Waynes book, I replaced the Fuel Filter and the Accumulator, now I am looking at replacing the check valve. So, here is the question...

Is the check valve on my 78SC internal to the fuel pump or is it something that can be swapped out without replacing the pump?

I wasnt able to find any check valves in the PP catalog that were made for the 78. The closest thing is one made for the 80-83s and the description indicates that the check valve "MAY" fit 78-83SCs along with a host of other years.

any help is greatly appreciated,

[Kemo]

after continuing research...it seems my car has the check valve built in. There is also talk of using a 1974 Banjo fitting of some sorts that contains a check valve. Has anyone done this?

Also, if i decide to replace the fuel pump, should I go with an 80-83 fuel pump that has an external check valve? if there is no difference between the years as far as pressure, i would think the 80-83 would be the way to go.

[Gunter]

Kemo:
Check valves can be internal or external on SC-pumps.
Bosch and Pierburg was used and both can be either way.
You don't know until you remove the pump and check visually.

A lot depends on what type/size of fuel line connector was used.
12 mm Banjo female-fittings were common with a male nipple threaded into the pump. This male nipple may, or may not, contain a check-valve.
I suggest you remove the steel plate and post a picture of your pump showing a close-up of the line connection so we can see what you have.
If the pump is old, replace.
Along with the pump, the short rubber hose from tank to pump is also replaced.
Ignore the red circle.