Re: [Chrysler300] 300H Fuel pump problem

[William Huff <whuff@xxxx>]

> Hi Mark and Group,


First of all, I seriously doubt that the push rod was made too short. To 
the best of my knowledge, all the "B" and "RB" engines, that is to say the 
350, 361, 383, 413, 426 and 440 cid engines, all use the same fuel pump 
push rod. I have also experienced difficulty removing them, but it has 
always turned out to be carbon and gunk built up on the cam shaft side of 
the rod, which jams in the hole bored in the block when you try to pull it 
out. Usually, persistence will pay off, keep trying, but don't use brute 
force, just keep pulling against the stoppage over and over again. I don't 
have an engine apart, but I seem to remember that you can access that end 
of the shaft with a small bent scraper by going through the fuel pump 
mounting hole which can be used to clean enough of the end of the rod to 
pull it through the hole. It may have been from the bottom with the oil 
pan off, my data retrieval isn't what it used to be.

In my opinion, if there is really any sort of mushroom on the end, the rod 
is ruined, and so is the camshaft eccentric that drives the pump rod. They 
depend on a mirror finish and hardened surfaces with lots of oil to work 
properly. It may be that the pump rod was not removed during rebuild, and 
hence is gunked up. By pushing the rod inward against the cam and slowly 
manually rolling the engine over, you can verify that there is a reasonable 
stroke being applied to the fuel pump lever. Use pliers or a stick to hold 
the rod, don't put your finger on the end of the rod while moving the 
engine or you may get a surprise. :^)

Have you verified that the fuel pump is correct for the application and is 
working properly? I have had 3 brand new Carter fuel pumps that didn't 
work properly. When compared to a known good pump, they seemed to have the 
wrong lever angle, so the stroke was very short. when installing the pump, 
be sure to hook the lever under the rod and then compress the pump to 
install the bolts. I think you could actually install the pump with the 
lever to the side of the rod if you forced it.

I have a GTX that has a Holley blue electric pump mounted in the trunk and 
a mechanical fuel pump for over 20 years now. It works well, we use both 
the ,mechanical and electric pumps when drag racing, even though the car is 
basically stock, there is a noticeably difference in performance without 
the electric fuel pump as a booster. I bought a Holley regulator and 
installed it before the carburetor, just in case. Hope this helps, good luck.

Bill Huff

> The root of my problem I think is a push rod that's too short in
> this "brand new" engine. I'm unable to get the rod out without dismantling
> the engine, as I believe the top of the rod may have a slight mushroom on
> it. I sure would like to meet the guy who "rebuilt" this motor. Is it that
> simple or is there something I'm overlooking? Will the carbs be able to
> regulate this pressure?
>
> Thanks for the help,
> Mark Souders