Fuel Pump Issue?

PaulB

Be Bold
Cross posted to FB. What should I do? My new engine build has a street grind cam. I just checked my fuel pump push rod and it looks to have 0.082" of throw; Well over the 050 I expected. It also starts about 030 deep at 0. The mechanical fuel pump seems to max out at 0.100". I can get close to zero at zero with two thick gaskets instead of the normal thick and thin; but should I? Will the system expand much under heat and bind? Should I pull the lower end apart and polish the pump lobe?
 

ng_randolph

Bjorn H
For the SOHC engines, gaskets are available in a variety of thicknesses, and you are supposed to pick the one that gives you the correct push rod protrusion. I would imagine the 850 is similar, so if two thick gaskets get you there, I think that would be fine. I would definitely not try to modify the cam lobe.

The fuel pump section of the X1/9 FSM can be found here, for reference.
 

tvmaster

True Classic
For the SOHC engines, gaskets are available in a variety of thicknesses, and you are supposed to pick the one that gives you the correct push rod protrusion. I would imagine the 850 is similar, so if two thick gaskets get you there, I think that would be fine. I would definitely not try to modify the cam lobe.

The fuel pump section of the X1/9 FSM can be found here, for reference.
Our local tech seems to think our X 1/9 ticking sound is coming from the mechanical fuel pump, and that it's the likely cause of the leaks I've been trying to trace. Are these easy enough to replace for someone who hasn't worked on an Exxe before? Will replacing the pump and gaskets get rid of the ticking sound, which speeds up with engine revs accordingly. Is it possible it's just the gaskets that are the problem, as opposed to both?
The parts aren't wildly expensive, but my concern is level of difficulty/diagnosis (he used a stethoscope)
 
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I don't know if the ticking is coming from the pump but it certainly could, especially if it was not installed properly. If the push rod gap was set too loose, that could cause the tick even if the pump is good. Check out how to set the gap in the service manual.
 

tvmaster

True Classic
I don't know if the ticking is coming from the pump but it certainly could, especially if it was not installed properly. If the push rod gap was set too loose, that could cause the tick even if the pump is good. Check out how to set the gap in the service manual.
Already did that reading thanks, and to me, it's beyond my scope. But for the average, U.S. mechanic, no problems? I'll take the Haynes in for him to look at...
 
Already did that reading thanks, and to me, it's beyond my scope. But for the average, U.S. mechanic, no problems? I'll take the Haynes in for him to look at...
It is pretty quick and easy to do, but there is a good chance you will get a little dirty.
 

kmead

Glutton for punishment
Already did that reading thanks, and to me, it's beyond my scope. But for the average, U.S. mechanic, no problems? I'll take the Haynes in for him to look at...
It is unlikely the fuel pump is the source of your oil leaks. It is almost guaranteed to be the oil pressure sender. Like 100% likely to be that. They all eventually leak. Even a ‘new’ modern one will eventually leak.
 

tvmaster

True Classic
It is unlikely the fuel pump is the source of your oil leaks. It is almost guaranteed to be the oil pressure sender. Like 100% likely to be that. They all eventually leak. Even a ‘new’ modern one will eventually leak.
Well, I've got leaks from both sides of the car. The sender is 100% for sure. I thought the transmission boot seal was the problem, but the leak on that side seems to be from above and to the left of engine center. The top looks good, so the pump gaskets were the next logical thing. It's really tough for a non-expert to pinpoint some areas in there
 
Well, I've got leaks from both sides of the car. The sender is 100% for sure. I thought the transmission boot seal was the problem, but the leak on that side seems to be from above and to the left of engine center. The top looks good, so the pump gaskets were the next logical thing. It's really tough for a non-expert to pinpoint some areas in there
Did you check the oil idiot light sender for leaks? It is on the front side of the head.
 

tvmaster

True Classic
Did you check the oil idiot light sender for leaks? It is on the front side of the head.
Nope, but if it’s in the service manual as ‘oil idiot light sender’, I’ll find it and have a look. ;)
Is front-side as obvious as it sounds?
 

milan1951

True Classic
For the SOHC engines, gaskets are available in a variety of thicknesses, and you are supposed to pick the one that gives you the correct push rod protrusion. I would imagine the 850 is similar, so if two thick gaskets get you there, I think that would be fine. I would definitely not try to modify the cam lobe.

The fuel pump section of the X1/9 FSM can be found here, for reference.
Here are new gaskets that I have to put in my new FISPA mechanical fuel pump installation on my 1982 X 1/9. Only have one gasket of same thickness as what I observed came off old fuel pump on the engine side. Other gasket would live on the fuel pump side of spacer holding rod in place. Have new spacer, gaskets in which to insert existing rod. At this stage will re-fit as I found on removal. Not having the benefit of measuring thickness or rod protrusion.

fuel pump gasket:s.jpgfuel pump spacer:rod.jpgFISPA fuel pump.jpg

Mike Salvador

1982 X 1/9 with carburettor
 
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