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Discussion Starter #1
New to me sled -- runs really rich...in fact the best way to start it is to pull the fuel pump fuse while pulling the rope.

Seems like I have read a bunch of posts about old fuel pumps causing over pressure issues -- seems like the pumps are discontinued -- 1670-635 and some of the parts online show output pressure of 45 which also seems (from what I have read) too high should be around 36?

I'll double check the pressure on my pump tonight but was just looking for some other things to check.
 

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That is a very common problem with the early Cat EFI's. KCCats used to make a fuel pressure regulator that would bring the pressure down to spec, you may want to give him a shout to see if he is still doing those...
 

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Welcome
Coupla things to try
On the clutch side supply hose, pinch it down with needle nose vise grips and not completely and see if it will start
If you are close to me I can lend you my gauge set up to test
You are correct at 36 psi (aprox)
If you remove the supply and add a 1/4" hose barb T and then a small piece of hose back to rail, then another longer piece to a 60psi gauge you can test your pump
Replacement pump should be rated at 45 psi and the fuel pressure regulator keeps it down by returning extra to tank.

I make up an adjustable fuel pressure regulator complete with a gauge so you can FINE TUNE EFI !
Yes TUNE so pipes porting shaved heads NO problem
 

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Discussion Starter #5
Thanks KCCats -- I can get the sled to run with the vise grips or pulling the EFI/Fuel pump fuse and get the timing right with putting the fuse back in before it dies...and pulling the rope about 327 times. Once its running its fine probably rich but it drives good.

Do you have a kit for sale for this sled still?
 

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Discussion Starter #7
Ok -- I re-tested the pressure and here is what I found
When the key is turned on and the pump builds pressure its right at 40PSI on my guage...but it drops to about 20 if I just let it sit...is that normaly or could it be the cause of the hard starting/flooding issue? Injectors leaking bye...they don't seem stuck open or anything because it will idle just fine.

Also when I do the injector test from the book with the wire i can hear them click open closed.
 

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Discussion Starter #10
Shouldn't the rail hold pressure at 40 or so once the pump stops running? Mine is dropping down after the pump stops -- leaking injector??
 
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