Timing Issue

[zupanj]

Changed title to reflect current diagnosis.

This not at all what I was expecting. My Runner wouldn't start last weekend and it was clearly fuel as the carbs were bone dry. I kept taking stuff off and really couldn't see a problem. I have an electric pump on the back in-line with the mechanical pump so I thought I should be golden. I recently put a vapor separator on to make it look more factory and it seems the electric pump was just pushing fuel back into the return line but couldn't push it to the carbs on it's own. So thinking about it I wondered if the brass tip on the fuel pump pushrod could have worn down and so the mechanical pump was no longer working. I ordered a new pushrod from Mancini that came this afternoon. After taking the pump off and removing the pushrod, I found what you see in the pics. The brass end looks good but the pump end is mushroomed like crazy. Also it looks like the fuel pump arm is worn down significantly but it is hard for me to tell since I don't have a new one to compare. I don't know what to think about this nor how to fix as that side is clearly not getting oil. Any thoughts from you guys? Also it looks to my eye though I haven't measured yet that the new pushrod has a slightly smaller diameter. Does this matter? I may post this elsewhere to see if anyone has any ideas.

 

[metalstorm]

Re: Fuel Pump Issue

The push rod only looks a little shorter and I would think it was still pumping something.The narrower pushrod will be ok unless it is more than .005 smaller.

 

[69hemibeep]

Re: Fuel Pump Issue

Jack it happens, your rod has gone soft :lmao: Are you running an oil slinger on the crank? I think that's how they get oil and Ive seen threads on other sites saying they are not needed with todays seals like all they did was keep oil away from the front seal. That should have still pumped fuel, but if mine sets for a week the carbs go dry and the fuel line from the pump to the carbs empties back to the tank through the return.

 

[zupanj]

Re: Fuel Pump Issue

That happens a lot these days. :huh: I have sure seen much worse so I am a little surprised at this. There is maybe a quarter inch chewed off the rod which doesn't seem like that much compared to a pic Stu posted on fbbo a while back. I will put it back together and see what happens. I am wondering why the electric pump didn't push fuel up to the carbs on it's own. I didn't put a filter back there so I wonder if a piece of debris got picked up at the pump inlet.

Bob I don't know if I have an oil slinger as I bought the engine already put together. This engine has always been slow to start but it always started until now.

 

[JJRJR]

Re: Fuel Pump Issue

Same thing just happened to me. I took the mechanical pump out completely and just using a Mallory electric pump and regulator. Installed an inline PSI gauge and it runs 7 lbs all day.

 

[george68hemirr]

Re: Fuel Pump Issue

Same thing just happened to me. I took the mechanical pump out completely and just using a Mallory electric pump and regulator. Installed an inline PSI gauge and it runs 7 lbs all day.

:yeathat: :yeathat: :yeathat:

jack.....are you adding zinc to your oil??

 

[zupanj]

Re: Fuel Pump Issue

Well I mis-diagnosed the problem. Put everything back together and am getting fuel but the thing still would not start. The fuel line to the carb still is not full but as I think about it, that is probably because the fuel goes back via the return line. I am getting a strong spark from the coil and replaced the distributor cap just because I had one around. The only clue was that it was really hard to start the week before. I figured I had flooded it and it ran OK once started.

Yesterday it would spin while sounding dead and then almost fire but not quite. I now think it has to be timing because that is all that's left. I have a bronze distributor gear and have been meaning to check timing for a while. Still the bronze tip on the pushrod didn't show any wear. I will put a light on it today now that the wife is home to spin the engine. I wonder if this is the source of the stumble I've been blaming on carbs as well.

I don't use a zinc oil additive George. My understanding is that is only required for cam break-in and not every day driving.

 

[69hemibeep]

Re: Fuel Pump Issue

I use a zinc phosphorus additive all the time in all my old flat tappet engines. All the old oils all had it before catalytic converters started to fail, its one of the reasons all the new mills have roller cams or over head rollers in them now

 

[ACME A12]

Re: Fuel Pump Issue

I use a zinc phosphorus additive all the time in all my old flat tappet engines.

:yeathat:

 

[metalstorm]

Re: Fuel Pump Issue

did you pull the plugs and clean them or put new one in?try starting fluid?A basic check for timing is pull the dist cap and crank the engine to TDC and see where the rotor points.

 

[moparchris]

Re: Fuel Pump Issue

I use a zinc phosphorus additive all the time in all my old flat tappet engines.

:yeathat:

X3 but I think Jack has a roller as he has a brass tipped pushrod (that doesn't sound quite right does it?)

 

[zupanj]

Re: Fuel Pump Issue

[/quote]X3 but I think Jack has a roller as he has a brass tipped pushrod (that doesn't sound quite right does it?)[/quote]

Yeah, it's a hydraulic roller but it probably wouldn't hurt to use the stuff. What brands do you use?

 

[zupanj]

Re: Fuel Pump Issue

Update:

It's definitely timing. I set the damper to 0º, top dead center (I am pretty sure but I didn't take the valve covers off). The rotor is pointing two cylinders past #1 so that's about 90º off!!!! I can't even imagine how this is possible, I can't rotate the distributor body enough to compensate for that. I haven't pulled the distributor yet so the source of the problem is still up in the air. It's a real mystery to me.

 

[zupanj]

The mystery deepens. Pulled distributor and it looks brand new. No problems with the shaft or on rotation. Pulled the bronze gear/oil pump rod, it also looks brand new. I am 90º out of phase and can't find out why. Is a check of the timing chain and the front of the engine the next move?

 

[sixgunrunner68]

Are you sure number one cylinder was on compression stroke. May have to go around again. Crank spins 2:1 cam. Would have ran like shit if at all that far out.

 

[zupanj]

I am not positive but pretty sure that I am at top dead center. As I said I didn't pull the valve cover to monitor valve movement. However even if the engine turns another 360º it will still be two cylinders off. The rotor is now pointing at the #4 terminal now. If the rotor turned 180º, it will be pointing at #7. So either way it's 90º out of phase.

You are right about it not running. It wouldn't start which how I got into this.

 

[ACME A12]

Well it was running previously...so as much attention needs to be paid as to how it got to this state as well as effecting a fix. Something happened...it didn't just wake up one morning and decide to be 90º out...and you don't want it to happen again...

As it was a crate motor I'm guessing that you have no idea what the timing chain set-up looked like prior to initial fire-up...and if you can't rotate the dizzy far enough to compensate then it probably wasn't a simple matter of the dizzy hold-down coming loose and allowing rotation until it was completely out of phase. I think you're looking at the front of the engine for clues now...

 

[69hemibeep]

Make sure your at TDC before you tear anything apart

 

[george68hemirr]

IT MAY HAVE JUMPED A GEAR ON THE TIMING CHAIN.......I THINK LOOKING AT THE TIMING CHAIN WOULD BE A GOOD IDEA.....WHATS EVERYONE THINK???....ALSO PULL OFF THE VALVE COVERS TO CHECK VALVE MOVEMENT

#1 TDC FIRING........INTAKE...#2&7 INTAKE AND EXHAUST #4 &8 VALVES SHOULD BE CLOSED AND SET FOR CHECKING LASH....HYD 0 LASH

 

[droptop]

Before pulling the chain cover, I would look at the oil pump shaft gear. It could have jumped time there as well. Just pull the distr. and you should be able to see the gear on the oil pump shaft as well as the gear on the camshaft.