- May 15, 2011
- Reaction score
- My Car
- 1971 Mach 1 Mustang
Well, I think I found the true source of the failure. Into the confessional of stupidity I go my friends.
Today I noticed something a little off when looking at the engine and heads. It appeared that the water jackets had quite a bit of rust in the heads. When I looked closer I found that the drivers head gasket had been inverted, blocking the front side water flow. This makes sense as the head likely got early hot, causing he exhaust valve to seize in the guide, this drawing the failure.
Why it did not happen sooner is beyond me! The Machine shop feels that was the driver to my demise. I feel really stupid because I have built enough engines to know to watch for details like that. I must have been in a rush that day and made the error. We will see if the head can be salvaged, or if I need to replace the one head.
Steel Gear for the Distributor. The gear on my distributor attracts a magnet. Should I still order a "Steel" gear for my roller cam since the cast iron gears would draw a magnet too?
Step one: ensure distributor gear depth is correct, if it's sitting too low you'll bind the gear into the mating pad in the engine block guillotineing the roll pin. When depth is verified move to Step two: simply drill out the roll pin hole to the next larger size (remember you already verified proper gear seating depth). I generally like HV pumps, I've enjoyed excellent success with many Clevelands over many years using the above simple process.BLUF: I sheared the dizzy gear roll pin yesterday at highway speed. Need to know how to get her back on the road.
351C 4v quench chamber , 4 speed car with 3:25 gears in the back. Motorsport M6250-A341 cam, non roller. About 1000 miles on the engine. Car was running great, oil pressure at the top of the gauge, temperature at the low end of normal. Ran westbound on the interstate for about 5 miles, reached speeds of 90 mph with no problems. stopped at a shop to see if a friend was there, it idled well and had no problems getting back up onto the highway. Cruising in traffic at about 70 MPH I suddenly lost power followed by loud explosive pops that I could feel in the floorboard.
I pushed the clutch in and saw the tach at 0 as I am losing speed in the center lane of the highway. I try engaging the clutch to restart the engine and was greeted with more loud explosive banging. I coasted to the shoulder of the highway and tried restarting. It would crank but not fire.
looking under the car I found that both Turbo Mufflers on the dual exhaust were blown wide open. Upon checking the rotor in the distributor I found the rotor could spin fairly freely, I could feel the drag of the oil pump, but it was not engaged with the cam.
Had it towed home, pulled the Dizzy and found the pin was sheared. The gear shows no sign of damage, just a sheared pin.
how do I fix this and make it reliable? I have a high volume oil pump which is likely the cause of the additional load on the dizzy gear according to some web research. Of course other sources say the gear should be pressed on, which I have never seen on a Ford. Will a higher strength roll pin solve the problem, or make me lose the oil pump drive shaft?
Note, the dizzy was a Rock Auto refurbish unit, so I got whatever gear and roll pin they put in.
Sorry to disagree, but an HV pump caused my newly rebuilt Cleveland to destroy a cam along with the mains. The builder chose to put this in and cost him a warranty rebuild. In a stockish motor it's just not needed imo.Step one: ensure distributor gear depth is correct, if it's sitting too low you'll bind the gear into the mating pad in the engine block guillotineing the roll pin. When depth is verified move to Step two: simply drill out the roll pin hole to the next larger size (remember you already verified proper gear seating depth). I generally like HV pumps, I've enjoyed excellent success with many Clevelands over many years using the above simple process.
I would look up the cam manufacturer and see what type of gear they call for on that particular cam. I would also make sure that you fit the gear to be within the specs. Make sure you use some gear break in lube.Steel Gear for the Distributor. The gear on my distributor attracts a magnet. Should I still order a "Steel" gear for my roller cam since the cast iron gears would draw a magnet too?
For a roller cam, a steel gear distributor should be used.
I have also drill the gear and shaft to add a second pin
Just curious but why did you get a bronze gear. If the manufacturer called for it than great. If your cam will work with a steel gear than I would go with what you have.OK, I go my new MSD Bronze gear today and I am at another question point.
So the MSD package say to send your Ford Distributor in to have the gear pressed on as it requires special tools.. So I am wondering if I just send the $80 gear back and change to a new or second hand Duraspark. Seems like I learn that I know less every day. I go with a roller cam, so I need a new gear, The gear needs a special install…….
I am an old school guy that used to say if it’s a Ford Distributor, stick it in there as we all had Clevelands back in High School. I have always seen people upgrading ignition with coils, HEI, and electronic. Does it really make any difference? My experience with Pertronix was not good, but I am feeling like I am wasting money with spending that much on a gear I have to go have pressed on.. The 2 distributors I have now are a Rock Auto refurbished auto lite that needs a clean hole drilled for the gear, and an generic replacement Dizzy from O’Reilly that I was running when the engine failed.
If I switch to a new duraspark kit, will it come with a gear, or will I need this gear anyway? Any help is appreciated.
I would agree with you absolutely as the shafts are not a large enough diameter to safely allow for drilling more and more holes.All good advice from fellow members. As another option I've used distributor to block shims to FINE tune the final gear height, thus avoiding drilling the "second hole" thru the shaft. As previously mentioned, replacement gears are hit and miss with their hole height dimensions. Most macine shops or driveline shops will have shims that will work with our Fords with minor "tweaking". The shims in my arsenal are .005, .010, .015. For me a simple 1 or 2 shims is preferable to drilling another shaft hole, in addition after two shaft hole drilling the third replacement gear my have a different hole height yet again! A distributor shim takes care of this never ending variable ESPECIALLY with Bronze gears.
KC, I got curious exactly what the spec is for a 351C dist, shaft end play allowance. The Ford manual shows .024 - .035", and gear location as 4.031 - 4.038". So you're right, there is quite o lot of free play allowed, meaning the gear will tend to find its own position. None the less, I wouldn't want to be outside of those tolerances.Thanks fort he responses.
3) I see all the shim guidance and have to ask how critical that is. I say this because the Autolite Dizzy I have that was a ROck Auto refurbish has about .030 or more vertical play in the shaft . So when I tighten the dizzy down that whole gear and shaft through the middle has float, right?
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